Welcome to "The first Edition of the African Conference on High Energy Physics (ACHEP)" to be held from 23 to 27 October, 2023 in Morocco. This first edition is organized by the Rabat-Salé-Kénitra Regional University Consortium and hosted by Rabat and Kénitra Universities: Main Web site.
ACHEP is a biennial international conference series on High Energy Physics held in African Institutes. The ACHEP brings together specialized scientists in the field of High Energy Physics from universities and research institutes all over the world on African grounds to discuss current developments and new trends, results, and perspectives in this field. The primary goal of ACHEP meetings is to encourage young African researchers and HEP experts to express and discuss new ideas.
The Standard Model of particles describes the fundamental constituents of matter and their interactions. Its predictions are probed in measurements at the LHC. In this talk, recent measurements by the ATLAS experiment are presented. They range from measurements of multijet and -photon production, high precision measurements using single W or Z bosons to measurements of multiboson production. Particular highlights are measurements that determine the strong coupling constant alpha_S and the W boson mass. Moreover, high-precision, differential measurements of multijet event shapes, the pT of the W and Z bosons, and the production of vector bosons in association with jets are discussed. They probe perturbative QCD and are compared to state-of-the-art theoretical predictions. Furthermore, measurements sensitive to trilinear and quartic electroweak gauge couplings are presented. These test the gauge structure of the electroweak theory and the agreement of the measurements with data are quantified by setting limits on Wilson Coefficients in the Standard Model Effective Field Theory.
The talk will cover the recent results on Standard Model measurements made by the CMS Collaboration, with particular emphasis on the Electroweak Sector of the theory.
The ATLAS experiment has performed extensive searches for rare Standard Model processes involving top quarks. In this contribution two recent highlights of this programme are presented. The top-quark pair production in association with a W boson is a difficult process to calculate and model and is one of the leading sources of same-sign and multi-lepton events. To improve our understanding of this process, a new inclusive and differential measurement of this process in events with 2 or 3 leptons was performed, as well as measurements of the ratio of ttW events with a positively and a negatively charged W-boson. The result confirms the slight tension observed in previous measurements. The 4-top production process, with a cross section of approximately 12 fb, is nearly one order of magnitude still. A re-analysis of the run 2 dataset is performed in the same-sign and multi-lepton channel, with several improvements in the event selection, the data-driven background estimate and the final discriminant. The cross section measurement of 23 +/- fb, is presented, as well as bounds on the top quark Yukawa coupling and on EFT operator coefficients affecting 4-top production.
The production of colored particles with large transverse momenta is almost always associated with presence of jets. The processes where three jets emerge in the final state are present in a lot of ATLAS measurements. Proper understanding and modelling of these processes is therefore crucial for today’s high energy physics.
POWHEG generator, as well as other matrix element generators, offer next-to-leading order (NLO) precision for trijet production. However to better understand also regions where final state jets acquire high transverse momenta, the production of pT sliced sample is necessary. Such a production is available in POWHEG generator by setting generation cut on jet pT and eliminating population of low pT regions by introducing so-called Born suppression factor, which serves for suppressing cross section for events based on their jet pT .
In the studies presented, The trijet events generated with Powheg+Pythia8 generator are compared to unfolded ATLAS data generated at √s = 13 𝑇𝑒𝑉 and compared with the already available dijet samples. The RIVET Toolkit (Robust Independent Validation of Experiment and Theory) is aimed for validation of MC samples, it allows to perform quick comparisons between the two models for a wide variety of observables used in many ATLAS analyses. It provides a large (and ever growing) set of experimental analyses useful for MC generator development, validation, and tuning, as well as a convenient infrastructure for adding your own analyses.
The gravitational-wave window onto the Universe has been opened with the first detection of a binary black hole in 2015. Since then, the LIGO-Virgo-KAGRA Collaboration has published 90 probable detections from three complete observing runs of the advanced-generation laser-interferometric detectors. These have enabled many new insights into the astrophysics of compact objects and the evolutionary history of massive stars, and are a completely novel probe for cosmology and fundamental physics. Since May 2023, the fourth observing run is ongoing, planned to last for 20 calendar months. It provides the deepest yet reach into our Universe's population of merging compact objects, with public alerts sent out in low latency to enable multi-messenger astronomy. We could also, for the first time, be able to detect a large variety of other sources such as spinning neutron stars or supernovae. Further, gravitational waves can probe many exciting channels for physics beyond the Standard Model.
The groundbreaking detection of gravitational waves generated by compact binary mergers ignited the birth of gravitational wave astronomy. In less than a decade, the Earth-based network of advanced interferometers, LIGO, Virgo, and KAGRA, has transformed various scientific fields, from astrophysics and cosmology to nuclear and fundamental physics, reshaping our understanding of the universe.
Despite these achievements, a substantial family of signals remains unobserved by these detectors: the continuous and/or stochastic gravitational waves. These signals, characterized by their persistent nature, can arise from a variety of sources, such as galactic fast-spinning neutron stars, elusive dark matter candidates, or events dating back to the early evolution of the universe.
In this talk, I will present an overview of the results of the searches for persistent sources during the last observing run, discussing some of the astrophysical and cosmological implications of these searches.
The LHAASO collaboration has more than 280 members from 32 institutes in 5 countries. The commission of LHAASO in 2021 opened the epoch of ultra-high-energy (UHE) gamma-ray astronomy and paved the way to address the origin of cosmic rays up to hundreds of PeV. Located at Daocheng, Sichuan, on the eastern edge of the Tibetan plateau with an elevation of 4410 meters above the sea level (Figure 1), LHAASO’s KM2A and WCDA arrays have achieved a duty cycle better than 99% and 98%, respectively, and the WFCTA has collected more than 2100 hours of high-quality data.
With a large FOV and high sensitivity, LHAASO-KM2A and WCDA have shown their superiority in UHE and very-high-energy (VHE) gamma-ray sky survey with the release of the first LHAASO catalog [1]. 90 sources with an extension less than 2︒ were detected with a significance greater than 5σ(TS>37). Among these sources, 69 were detected by WCDA, 75 by KM2A and 54 by both arrays (Figure 2). The mean spectral index of KM2A sources is about 3.5 while those for WCDA sources is 2.5. 43 UHE sources were detected above 100 TeV with a significance greater than 4σ. There are 82 sources within the Galactic latitude of 12︒, and 4 high latitude AGNs. 32 of these sources haven’t been detected previously in the TeV range (Figure 2). Half of these sources can be associated with pulsar wind nebulae or supernova remnants (SNRs), 1 with AGN, 8 have GeV counterparts, 7 have no counterpart. Diffuse gamma-ray emission from the Galactic plane was also measured from 10 TeV to 1PeV [2]. The brightest gamma-ray burst 221009A was also fully covered by LHAASO [3]. Some preliminary results on cosmic ray spectra, composition, and anisotropy are also available. These results together will advance our understanding of the origin of cosmic ray significantly.
In particular, more than 7 SNRs have been detected by LHAASO (Figure 3). There are also a few UHE sources likely associated with SNRs. The spectra of some of these sources extend beyond 100 TeV, implying that they are indeed PeVatrons. However, their soft UHE spectra means that both leptonic and hadronic processes can account for the observed UHE emission. Detailed multiwavelength studies are needed to quantify their contribution to PeV cosmic rays [4]. More exciting developments can be anticipated in the coming few years.
The thermal phase transitions of the AdS black holes are controlled through a stochastic process and are a function of an order parameter. The dynamics during its phase transitions is determined through the fluctuating macroscopic variables, we recall the Fokker-Planck equation to study the evolution of such a process in the Born-Infeld-AdS background. Moreover, we discuss about the critical points and their topology during thermal phase transitions of the Born-Infeld AdS black holes. Such investigations are made using two different topological approaches, namely, using Duan’s topological current $\phi$-mapping theory, and the off-shell free energy. Within Duan’s formalism, we observe that for a given value of the Born-Infeld parameter $b$, there exists a connection to the charge parameter $Q$, which is highly sensitive to the topological phase transitions. This way we examine the connections of the first-order phase transition with the topological nature of the critical points to find the possible breakdown in certain parametric ranges. As the second approach, we call the offshell free energy to determine the topological classes: of which one corresponds to the AdS-Schwarzschild black hole phases, while the other corresponds to the AdS-Reissner–Nordström black hole phases providing a topological phase transition.
We start with a general introduction to the problem of neutrino electromagnetic properties [1]. Then we consider the most stringent experimental constraints on neutrino magnetic µν and electric dν moments, millicharge qν, charge radii <rν2> and anapole aν moments from the terrestrial experiments (the bounds from MUNU, TEXONO, GEMMA, Super-Kamiokande, Borexino, COHERENT, XENON1T, CONUS and the most recent bounds from XENONnT [2] and LUX-ZEPELIN [3]). Then we focus on the main manifestation of neutrino electromagnetic interactions, such as: 1) the radiative decay in vacuum, in matter and in a magnetic field, 2) the neutrino Cherenkov radiation, 3) the plasmon decay to neutrino-antineutrino pair, 4) the neutrino spin light in matter, and 5) the neutrino spin and spin-flavour pre-cession are discussed. Phenomenological consequences of neutrino electromagnetic interactions (including the spin light of neutrino) in astrophysical environments are also reviewed. The best bounds from laboratory experiments and astrophysical observations on neutrino electromagnetic properties are confronted with the predictions of theories beyond the Standard Model.
[1]C.Guinti, A.Studenikin, Neutrino electromagnetic interactions: A window to new physics, Rev.Mod.Phys.87 (2015) 531.
[2]A.Khan, Light new physics and neutrino electromagnetic interactions in XENONnT, Phys.Lett.B 837 (2023) 137650.
[3]M.Atzori Corona et al., New constraint on neutrino magnetic moment from LZ dark matter search results,Phys.Rev.D107 (2023) 053001.
The latest results of the DANSS experiment are presented. DANSS is a one cubic meter highly segmented solid scintillator detector. It consists of 2500 scintillator strips, covered with gadolinium loaded reflective coating and read out with SiPMs and PMTs via wavelength shifting fibers. DANSS is placed under a 3.1 GW industrial reactor at the Kalinin NPP (Russia) on a movable platform. The distance from the reactor core center is varied from 10.9 m to 12.9 m on-line. The inverse beta decay (IBD) process is used to detect antineutrinos. DANSS detects about 5000 IBD events per day with the background from cosmic muons at the level of few percent.
The total number of the detected antineutrino events has reached 7M with about 1.5M new events in excess of the one year old data. New limits on the sterile neutrino oscillation parameters will be presented. The evolution of the antineutrino counting rate and spectrum with the time of the reactor campaign will also be discussed. An analysis of the data, including the absolute antineutrino flux with conservative estimation of systematic uncertainties, excludes nearly the whole area of the sterile neutrino parameters, preferred by the recent BEST results, and also the best fit point of the Neutrino-4 experiment.
The status of the coming DANSS modernization will be presented. This upgrade will
improve DANSS energy resolution and increase the sensitive volume, which will allow covering of even larger area of the sterile neutrino parameters. The sensitivity of the upgraded DANSS detector will allow to check the latest BEST and Neutrino-4 results in a model-independent way.
In this work we derive limits on the WIMP-nucleon scattering cross-section by comparing the potential heat flow within the Earth from Dark Matter capture and subsequent annihilation to the observational value. This effect has been argued previously in the literature to provide a potential link to mass extinction phenomena on Earth. However, we focus on whether additional heat-flux from dark matter annihilations within the Martian core could have affected the decay of its geodynamo, and thus precipitated its magnetic field loss. We determine that Xenon1T limits on the WIMP nucleon cross-sections do not allow sufficient heating to significantly affect either Earth or Mars. We then use this to determine the local dark matter density that would support a significant effect given these limits. In addition, we have extended previous work on this topic by including resonant collisional effects, considering the impact of Xenon1T limits, and by considering possible effects on the evolution of the Martian geodynamo.
Darkside-20k, an underground dark matter search experiment located at
LNGS (Italy), aims to achieve a total exposure of 200 tonne-years
devoid of instrumental backgrounds. At its core is a dual-phase Time
Projection Chamber (TPC) containing 50 tonnes of low-radioactivity
liquid argon. Surrounding the entire TPC wall is a gadolinium-loaded
acrylic material, serving as a neutron veto. This material is immersed
in a second low-radioactivity liquid argon bath, enclosed within a
stainless steel vessel. The entire detector is housed in a cryostat
similar to protoDUNE, which is filled with 600 tons of Atmospheric
Argon. Both the TPC and neutron veto feature large-area Silicon
Photomultiplier (SiPM) array detectors.
Construction of Darkside-20k has commenced, with data-taking scheduled
to start in 2026. The presentation will outline the current progress
of Darkside-20k's development and construction, as well as discuss the
future plans for liquid argon dark matter experiments, including
DarkSide-LowMass.
Additionally, the presentation will provide an overview of recently
published findings from the predecessor experiment, DarkSide-50.
Specifically, it will focus on the search for low-mass dark matter and
the analysis of dark matter annual modulation.
Since the beginning of its full operation in 2011, the IceCube Neutrino Observatory at the South Pole station, has pioneered many discoveries in neutrino astronomy, cosmic ray physics, and particle physics. This talk will present the experiment, and highlight recent discoveries, such as the evidence for neutrino emission from the active galactic nucleus NGC 1068, the first observation of neutrinos coming from the Galactic Plane, and the detection of a Glashow resonance event. The ongoing extension of the current detector, the IceCube Upgrade, will push IceCube’s energy threshold to a few GeV, and enhance the understanding of the detector systematics, with the installation of over 700 novel optical sensors, and some 50 calibration devices. Finally, we introduce IceCube-Gen2, the proposed next generation of the observatory, aimed to build upon the experience and discoveries of the past decade.
The KM3NeT collaboration is constructing two last-generation underwater neutrino telescopes in two abyssal sites of the Mediterranean Sea. The scientific goal is to complement the IceCube sky coverage, instrumenting a comparable detection volume and improving the reconstruction accuracy.
Each telescope is a Cherenkov detector built with the same technologies but with a different geometrical layout. Thanks to such two installations, KM3NeT can cover a large neutrino energy range thus addressing various science topics.
ARCA (Astroparticle Research with Cosmics in the Abyss), 100 Km offshore Portopalo di Capopassero (Sicily) and at a depth of 3500 m, is designed for the detection of high-energy astrophysical neutrinos in the energy range of TeV-PeV; ORCA (Oscillation Research with Cosmics in the Abyss), 40 km offshore Toulon (France) and at a depth of 2500 m, is optimized for the detection of less energetic neutrinos starting from few GeV.
The multi-PMT optical module design provides high resolution, good positioning and timing calibration.
In this talk, an overview of the technology developed for the construction of the telescopes and their current status will be presented. The expected performance of the full detectors and some preliminary results obtained with the first deployed detection units will be reviewed.
Neutrino experiments based on water-Cherenkov detectors have made significant contributions
to our understanding of neutrino physics, but they face challenges in accurately modeling
detector systematic parameters due to their large size and the smallness of the cross-section
for weak interactions. While these experiments have achieved remarkable successes in the
past, the future era of precision neutrino physics demands innovative techniques to better
comprehend detector systematic uncertainties.
In this talk, I will present modern ideas to represent neutrino event topologies in preparation
for the Hyper-Kamiokande experiment. Hyper-Kamiokande, a next-generation underground
water-Cherenkov detector, is poised to begin construction in the near future and will
serve as a far detector, positioned 295 km away, for a long baseline neutrino experiment utilizing
the upgraded J-PARC beam in Japan. Moreover, it will have the capability to detect
proton decay, atmospheric neutrinos, and neutrinos from astronomical sources with unprecedented
sensitivity compared to its predecessor, Super-Kamiokande.
To address the challenges of modeling systematic uncertainties, I will explore the application
of view rendering techniques, including Neural Radiance Field (NeRF), which can
implicitly encode crucial detector parameters such as water attenuation length and scattering.
Furthermore, these techniques can be employed in event reconstruction, generating new events
to enhance the understanding of systematic uncertainties. The ongoing work presented here
aims to achieve computationally efficient and comprehensive treatment of systematic uncertainties
by accelerating simulations and event reconstruction, enabling the variation of detector
parameters for large water-Cherenkov detectors.
SBND is a 112-ton liquid argon time projection chamber located on the Booster Neutrino Beam at Fermi National Accelerator Laboratory, and is the near detector of the Short-Baseline Neutrino program. The primary goals of SBND are to provide flux constraints for sterile neutrino searches, conduct world-leading neutrino cross-section measurements on argon, and perform beyond the Standard Model (BSM) physics searches with its large neutrino beam flux and high-precision particle identification capabilities. In this talk, I will discuss SBND’s prospects for detecting a variety of BSM phenomena produced in a neutrino beam, such as sub-GeV dark matter, dark neutrinos, millicharged particles, and others.
The ANTARES detector is an underwater Cherenkov neutrino telescope. Its construction was completed in 2008 and it operated for sixteen years in the Mediterranean Sea. Even though optimised for the search for cosmic neutrinos, this telescope is also sensitive to exotic particles like magnetic monopoles and nuclearites (massive nuggets of strange quark matter). We discuss here the possible detection of magnetic monopoles and non-relativistic down-going nuclearites with the ANTARES telescope and present the results using data collected over the period from 2009 to 2017.
We discuss as accurately as possible the cross section of quasi-elastic scattering of electron (anti-)neutrinos on nucleons, also known as inverse beta decay in the case of antineutrinos. We focus on the moderate energy range from a few MeV up to hundreds of MeV, which includes neutrinos from reactors and supernovae. We assess the uncertainty on the cross section, which is relevant to experimental advances and increasingly large statistical samples. We estimate the effects of second-class currents, showing that they are small and negligible for current applications.
The experimental and theoretical research on the physics of massive neutrinos is based on the standard paradigm of three-neutrino (3ν) mixing, which describes the oscillations of neutrino flavors measured in solar, atmospheric and long-baseline experiments. However, several anomalies are short baseline oscillation data, corresponding to an L/E of about 1m/MeV could be interpreted by involving a hypothetical fourth neutrino such as reactor antineutrino anomaly (RAA) and Galium anomaly.
The STEREO experiment was designed to investigate this conjecture, which would potentially extend the Standard Model of particle physics. The STEREO detector (has segmented design) is a high-precision very-short-baseline experiment studying 235U antineutrinos produced by highly enriched nuclear fuel. Located at about 10 meters from reactor core at the research of Institut Laue-Langevin (Grenoble, France), and are detected in six cells Gd-loaded liquid scintillator volumes via the IBD process.
STEREO provides a complete study of all anomalies for a pure 235U antineutrino spectrum, using HEU ILL core (93% 235U).
This presentation will describe an analysis of the full set of data generated by STEREO and an accurate prediction of the reactor. The measured antineutrino energy spectrum suggests that anomalies originate from biases in the nuclear experimental data used for the predictions, while rejecting the hypothesis of a light sterile neutrino. Our result supports the neutrino content of the Standard Model and establishes a new reference for the 235U antineutrino energy spectrum.
The SND@LHC experiment at the Large Hadron Collider is a new neutrino scattering experiment, that got approved and installed in 2021.
We report the direct observation of muon neutrino interactions with the SND@LHC detector using a dataset of proton-proton collisions at 13.6 TeV collected in 2022 and corresponding to an integrated luminosity of 36.8 fb−1. The search is based on information from the active electronic components of the SND@LHC detector, which covers the pseudorapidity region of 7.2 < η < 8.4, inaccessible to the other experiments at the collider.
We will discuss further physics prospects of SND@LHC, as well as future plans for an upgraded version of the experiment for the high-luminosity LHC running, planned for end if this decade.
The Belle II experiment at the SuperKEKB asymmetric-energy electron-positron collider has been collecting the world’s highest-intensity collisions at the $\Upsilon$(4S) since 2019. A data set comparable in size to that of predecessor experiments, Belle, and collected with the new detector, enables unique or world-leading results. Examples include indirect searches for non-standard-model physics in the weak interactions of quarks, determinations of fundamental standard-model parameters, and direct searches for low-mass dark matter. This talk presents a selection of recent Belle and Belle II results and briefly discusses future perspectives.
Production of muons from heavy-flavour hadron decays in pp collisions at √s = 13 TeV with the ALICE detector
Tebogo Joyce Shaba on behalf of the ALICE Collaboration
North-West University, South Africa
iThemba LABs, Cape Town, South Africa
Heavy quarks (charm and beauty) are produced in early stages of the hadronic collision via hard-parton scatterings. In ALICE, heavy-flavour particles are measured in the central barrel (|𝜂|<0.9) which is optimized for the reconstruction of hadrons, electrons, photons and jets, in the muon spectrometer (−4<𝜂<−2.5), which is responsible for the reconstruction of muons produced by decays of heavy-flavour hadrons, quarkonia and electroweak bosons via the single and di-muon decay channels. The inclusive single muon production cross sections from heavy-flavour hadron decays, produced at forward pseudorapidity, are measured using muon-triggered events in proton-proton (pp) collisions at √s = 13 TeV. The pT - differential cross sections are presented and compared to perturbative quantum chromodynamics (pQCD) calculations. These measurements provide a testing ground for pQCD calculations.
Cross section measurements are key to the ALICE physics program and require precise luminosity determination. In ALICE, the luminosity determination relies on visible cross sections measured in dedicated calibration experiments, the van der Meer scans. For the LHC Run 2 data samples, ALICE measured the luminosity with an uncertainty better than 2% for pp collisions and 3% for Pb-Pb collisions. In this talk, the methodology and results of the measurement will be presented and discussed. The first measurement of the inelastic hadronic cross section for Pb-Pb collisions at \sqrt{s_{NN}} = 5.02 TeV, obtained by efficiency correction of the visible cross section, will also be presented and discussed in the framework of available models.
ICTP Physics Without Frontiers (PWF) works to motivate, train, and educate physics and mathematics university students worldwide, with focus on science and technology lagging countries, to help build the next generation of scientists.
PWF organises projects working with volunteer scientists, who are PhD students, postdoctoral researchers, or lecturers from all over the world, who are passionate about promoting and supporting physics and mathematics. The Physics Without Frontiers Volunteer Network is composed of more than 100 passionate scientists primarily originally from the partnered countries.
Each PWF project is unique, combining hands-on training, lecturers and networking, developed with a country's specific needs in mind. A component of science diplomacy, interaction with industry, outreach and diversity are often incorporated into all projects. PWF promotes networking and collaborative environments, and its mentoring scheme is open to all students. PWF has worked with over 10000 students worldwide in 50 different countries!
The International Particle Physics Outreach Group (IPPOG) is a network of scientists, science educators and communication specialists working across the globe in informal science education and public engagement for particle physics. The primary methodology adopted by IPPOG includes the direct participation of scientists active in current research with education and communication specialists, in order to effectively develop and share best practices in outreach. IPPOG member activities include the International Particle Physics Masterclass programme, International Day of Women and Girls in Science, Worldwide Data Day, International Muon Week and International Cosmic Day organisation, and participation in activities ranging from public talks, festivals, exhibitions, teacher training, student competitions, and open days at local institutes. These independent activities, often carried out in a variety of languages to public with a variety of backgrounds, all serve to gain the public trust and to improve worldwide understanding and support of science. We will highlight, in this presentation, IPPOG collaboration links and activities in Africa.
The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) is not only a groundbreaking scientific facility but also a hub for international collaboration and knowledge exchange. Outreach, inspiration and education are some of the pilar missions of CERN, the LHC experiments are therefore committed to promoting global diversity and ensuring equitable access to scientific knowledge and opportunities worldwide. This contribution aims to highlight the outreach programs conducted by the LHC experiments, with a specific focus on activities and materials that hold immense value for Africa. These programs provide access to cutting-edge research facilities, science workshops and resources, remote access to LHC data, virtual lectures and webinars as well as access to collaboration platforms. They foster scientific curiosity, promote education and technology transfer to inspire the next generation of African scientists and researchers in the field of particle physics and beyond.
Agriculture, archaeology, biology, biomedicine, chemistry, cultural heritage studies, engineering, energy, environmental science, forensic science, geology, materials science, nanotechnology, new drugs, palaeontology, and physics are just some of the fundamental, applied, and industrial fields that are being revolutionised by the advent of advanced light sources
The SESAME 2.5GeV storage ring, designed to store 400mA electron beam current, is accommodating now 300mA beam current with a good lifetime of around 24h. SESAME has three operational beamlines with five other beamlines under various stages of construction or planning which are broadly broken down into three energy ranges – infrared (< 1 eV), soft X-ray (100 eV to 2500 eV) and hard X-ray (>2500 eV)
The BM02-IR microspectroscopy offers the users a non-destructive vibrational technique that combines the spatial resolution of a microscope together with the high chemical sensitivity of the IR spectrometer. In addition to the SR-IR source broad spectral emission and the wavelength characteristics, Infrared Synchrotron provide advantages in its brightness/brilliance (about 1000 times brighter) with a signal-to-noise ratio that cannot be achieved by the conventional sources.
The BM08-XAFS/XRF beamline is dedicated to synchrotron-based X-ray Absorption Fine Structure (XAFS) and X-ray Fluorescence (XRF). The source is one of the bending magnets of SESAME, and the optical configuration consists of a vertical collimating mirror, a double crystal monochromator and a focusing mirror, allowing measurements in the energy range from 4.7 to 30 keV, covering most of the elements in the periodic table starting from Ti.
The ID09-MS/XPD beamline is dedicated to X-ray diffraction investigations from polycrystalline materials. Temperature-dependent in-situ measurements up to 1000 °C are possible using a gas blower, and the beamline can be used for a wide range of applications, such as phase identification and quantitative phase analysis, microstructural investigations, Pair Distribution Functions (PDF), grazing angle and reflectivity measurements.
The ID10-BEATS beamline for X-ray Computed Tomography (XCT) has been inaugurated in June 2023. Funded by a European Horizon 2020 project, the beamline allows for various operation modes and ensures sufficient photon flux density in a filtered white beam (up to 100 keV) or monochromatic beam between 8 keV and 50 keV.
The ID11L-HESEB beamline provide soft x-ray analysis techniques to understand the atoms' electronic structure and chemical environment. Soft x-ray techniques are surface-sensitive because soft x-rays have a high interaction probability with matters and can be applied to low atomic number elements that are critical for life science, like Carbon, Nitrogen, and Oxygen.
The European research funding landscape offers several options for individual applicants. In particular, the most prestigious postdoc fellowship on the continent, the Marie Skłodowska-Curie programme, is open also to overseas applicants. I will share some experiences of how to successfully apply for this scheme, along with pointers to other more advanced grants (ERC). Very similar schemes are nowadays run by the UK and Switzerland, as well as additional options in individual EU member countries. Some of the tips will hopefully also be useful for applying to grants on other continents, or for regular job applications.
Nuclear material is nowadays widely used in many fields, such as health, environment, agriculture, and industry. Besides its use for public utility, there is also the possibility that nuclear materials could be used for illicit purposes. For this reason, it is important that not only expert personnel, but also technicians and, as much as possible, common people, starting from high-level school, can be aware of radiation and methods for detecting it. CAEN Training Courses and Educational Kits aim to give both a comprehension of nuclear physics phenomena and to provide state-of-the-art technologies, instruments, and methods.
The CAEN Educational kits are Silicon Photo-Multipliers (SiPM) based. Silicon Photo-Multipliers represent the state-of-the-art in low light detection, featuring single-photon sensitivity and unprecedented photon number resolving capability. Their characteristics make them increasingly attractive for a wide range of applications in the Nuclear and Particle Physics fields, including Science Education opening new perspectives in the exploration of the quantum nature of light.
The Kits consist of a series of experiments with different difficulty levels, covering from the fundamentals of Statistics to Nuclear Physics, Particles Detection, and Nuclear Imaging. Many applications are exploited in the Kits, starting from experiments about gamma and beta spectroscopy, and cosmic rays to applications like building a prototype of a Positron Emission Tomography scanner, detecting and measuring NORM (Naturally Occurring Radioactive Materials) and Radon, and measuring radioactivity on the field. All the necessary tools are included in the kit: detectors, as for example scintillating crystals like LYSO or CsI, a detection system based on Silicon Photo-Multipliers or Photo-Multiplier Tube, power supply and amplification module, and the digitizer to read out the signal. Small samples of common-use radioactive materials can be included as well. The user can acquire the energy spectra, calibrate them in terms of emitted energy, study the composition of different samples, etc. Finally, the new software platform called Hera makes available most of the experiences, giving the possibility to acquire the spectra and analyze them through integrated tools. Step-by-step instructions are given to guide even non-expert personnel towards the final measurement and combine theoretical background, hands-on setup operations, data analysis, and critical synthesis of the results for complete training.
Bertin Technologies is an industrial group that develops high-performance instrumentation for critical
or scientific applications, such as defense & security, nuclear & health physics, and space.
The SaphyRAD product line is composed of a wide range of probes dedicated to the detection of all
types of particles (alpha, beta, neutron, and gamma). The latest developed probe is a portable
gamma spectrometer for in-situ measurement and radionuclide identification. Its algorithm is based
on a new analysis approach in gamma spectrometry. To perform this analysis, the algorithm needs
a GEANT4-simulated reference database of the probe. This database is composed of a single library
of forty spectral shapes for industrial and medical radionuclides, natural and fissile materials.
This algorithm is embedded in a microcontroller to allow in-field measurements. It has shown very
good identification performance with high confidence level, especially at low statistics (≤ 10,000
events in the whole spectrum), even with up to five radionuclides simultaneously. It also allows fissile
material classification (enrichment level for uranium and plutonium). Because of its ability to perform
analysis at low statistics, the measurement time can be reduced to a few seconds, allowing operators
to react quickly to the threat. This performance could be applied to other nuclear measurement fields,
such as nuclear installation monitoring and dismantling, research applications, and whole-body
radiometry.
Many theories beyond the Standard Model (BSM) have been proposed to address several of the Standard Model shortcomings, such as the origin of dark matter and neutrino masses, the fine-tuning of the Higgs Boson mass, or the observed pattern of masses and mixing angles in the quark and lepton sectors. Many of these BSM extensions predict new particles or interactions directly accessible at the LHC. This talk will present some highlights on recent searches based on the the full Run 2 data collected by the ATLAS detector at the LHC with a centre-of-mass energy of 13 TeV.
A search for non-resonant Higgs boson pair (𝐻𝐻) production is presented, in which one of the Higgs bosons decays to a b-quark pair (𝑏̄𝑏) and the other decays to 𝑊𝑊∗, or 𝑍𝑍∗, or 𝜏+𝜏− , with in each case a final state with 𝑙𝑙 + neutrinos (𝑙 = 𝑒, 𝜇). Both gluon-gluon fusion and vector boson fusion are considered as production modes. Data recorded by the ATLAS detector in proton-proton collisions at a centre-of-mass energy of 13 TeV at the Large Hadron Collider, corresponding to an integrated luminosity of 140 fb−1, are used in this analysis. Events are selected to have exactly two 𝑏-tagged jets and two leptons with opposite electric charge and a large transverse missing energy (𝐸missT ) in the final state. These events are classified using multivariate analysis algorithms to separate the 𝐻𝐻 events from other Standard Model processes. No evidence of the signal is found. The observed (expected) upper limit on the cross-section for non-resonant Higgs boson pair production is determined to be 9.6 (16.2) times the Standard Model prediction at 95% confidence level. Likelihood scans for the Higgs boson self-interaction coupling parameter 𝜅𝜆 and the quadrilinear coupling parameter 𝜅2𝑉 are also performed in this analysis, constraining these parameters to be within the ranges [−6.2, 13.3] and [−0.17, 2.4], respectively, at 95% confidence level.
The axion particle discovery could answer the big CP problem as it is hypothetically predicted. Hence A study on the exotic decay of the Higgs boson to two Axion Like Particles (ALPs), which in turn decay to two photons, was carried out. This analysis covers the mass range of ALPs between 100 MeV and 60 GeV and ALPs-photon couplings C$_{a\gamma\gamma}$ of 10$^{-5}$ to 1, a region that includes signatures with significantly displaced vertices and highly collinear photons, which present the challenges of this analysis. No significant deviation from the SM expectations has been found, excluding a large parameter space of models that could have explained the (g - 2)$_\mu$ discrepancy.
Many extensions to the Standard Model (SM) introduce a hidden or a dark sector rising from an additional U(1)d gauge symmetry, to provide candidates for dark matter in the universe and a possible explanation to astrophysical observations such as the positron excess observed in the cosmic radiation flux. The gauge boson of the dark sector would be either a massless or a massive dark photon that can either kinetically mix with the SM photon, or couple to the Higgs sector via some mediators. If dark photons decay back to the SM particles with a significant branching ratio, we could either observe measurable deviations in some particular Higgs decay channels or new exotic signatures that would be accessible at the LHC energies. An overview of different dark photon searches using the ATLAS detector will be presented, targeting a wide range of Higgs bosons as well as dark photon masses. Experimental limits on the dark photon production in the ATLAS detector are presented for different Higgs boson production mechanisms.
First Physics Results from the FASER Experiment with LHC Run 3 Data
-on behalf of the FASER Collaboration
FASER, an experiment at the LHC, was designed to explore the existence of light, weakly interacting particles that are generated in proton-proton collisions at the ATLAS interaction point and travel in the far-forward direction. The initial data analysis focused on two searches: the decay of dark photons into an electron-positron pair and the charged-current interaction of muon neutrinos leading to the production of muons. The outcomes of these searches, with a dataset corresponding to an integrated luminosity of 27.0 fb$^{-1}$ collected at a center-of-mass energy of $\sqrt{s} = 13.6$ TeV during LHC Run 3 in 2022, will be presented.
For the dark photon analysis, no events were observed in an almost background-free analysis, resulting in world-leading constraints on dark photons with couplings in the range of $\epsilon \sim 10^{-5} - 10^{-4}$ and masses in the range of $\sim 10$ MeV - $100$ MeV. In the neutrino analysis, we identified $153^{+12}_{-13}$ neutrino interactions with a significance of 16 standard deviations above the background-only hypothesis. These observed events exhibit characteristics consistent with expected neutrino interactions in terms of secondary particle production and spatial distribution. Furthermore, they imply evidence for the detection of both neutrinos and anti-neutrinos with incident neutrino energies significantly surpassing 200 GeV.
We suggest an explanation for and explore the consequences of the excess around 95 GeV in the di-photon and di-tau invariant mass distributions recently reported by the CMS collaboration at the Large Hadron Collider (LHC), together with the discrepancy that has long been observed at the Large Electron-Positron (LEP) collider in the $b\bar b$ invariant mass. Interestingly, the most recent findings announced by the ATLAS collaboration do not contradict, or even support, these intriguing observations. Their search in the di-photon final state similarly reveals an excess of events within the same mass range, albeit with a bit lower significance, thereby corroborating and somewhat reinforcing the observations made by CMS. We have found that all three signatures can be explained within the general 2-Higgs Doublet Model (2HDM) Type-III.
We demonstrate that the lightest CP-even Higgs boson in this scenario can explain the excess in all three channels simultaneously, i.e., in the di-photon, di-tau and $b\bar b$ mass spectra, while satisfying up-to-date theoretical and experimental constraints. Moreover, the 2HDM Type-III predicts an excess in the $pp\to t\bar t H_{\rm SM}$ production channel of the 125 GeV Higgs boson discovered in 2012, with properties (couplings, spin and CP quantum numbers) consistent with those predicted in the Standard Model (SM). This effect is caused by a up to 18\% enhancement of the Yukawa coupling to top
(anti)quarks in comparison to the SM value. Such an effect can be tested soon at the High Luminosity LHC (HL-LHC), which can either discover or exclude the scenario we suggest. This unique characteristic of the 2HDM Type-III makes this scenario with the 95 GeV resonance very attractive for further theoretical and experimental investigations at the (HL-)LHC and future colliders.
In search of beyond standard model, several hints of the presence of a new state at about 95 GeV have recently been observed by both the ATLAS and CMS collaborations based on their full Run 2 data sets. This result becomes particularly intriguing when considering another excess reported by CMS in the di-tau final state at a comparable mass, which exhibits a similar local significance. Moreover, the LEP experiments observed
an excess in the same mass range of a Higgs boson decaying to pairs of a bottom quark and its antiparticle. By combining the two results of the CMS and ATLAS di-photon excesses, we suggest interpreting the three excesses (i.e., in the di-photon, di-tau, and $b\bar{b}$ decay channels) together within the context of a Two-Higgs doublet model extended
by a real Triplet scalar (2HDMrT), with focus on types I and III Yukawa textures. We find that the lightest CP-even Higgs boson in this framework can account for the excess observed in all three channels simultaneously while still being consistent with all other known limits and measurements related to the Higgs sector.
Gravitons are hypothetical particles that have yet to be directly observed, but they are predicted by various theories, including quantum gravity. One quantum mechanical process that allows for the production of particles that couple to photons, such as gravitons, is light-by-light scattering. While rare, this process can be observed and is sensitive to potential new physics beyond the Standard Model. The limits on the graviton-photon coupling have been set for masses of the graviton ranging from 100 MeV up to 2 TeV at the LHC, assuming a 100% branching ratio to photon pairs and with universal coupling. These limits have been extended to include also electron-positron colliders such as BelleII, BESIII and LEP.
We study the one-loop prediction for the single production of the Standard Model (SM) Higgs boson ($h_1$) in association with a photon in electron-positron collision in the context of the Two Higgs Doublet Type II seesaw Model (THDMcT). This type of process is directly sensitive to one-loop impacts because it has no amplitude at the tree level. The cross section in the standard model (SM) is maximal around$\sqrt s=250$ GeV, in this work, we demonstrate the extent to which the production rate can be increased or decreased by the introduction of new physics. We study the one-loop processes $e^+e^- \to h_1\gamma$ and $e^-\gamma \to e^- h_1$ with and without the modified Veltman conditions. We also discuss the correlation with $h_1\gamma\gamma$ and $h_1\gamma Z$ which are sensitive to the existence of singly and doubly charged Higgs. It is observed that charged scalars, when significantly coupled to a Higgs boson that resembles the Standard Model, can make substantial contributions to both the decay and production rates. For parameter points verified the actual experimental constraints and the theoretical constraints except the Veltman conditions, our numerical results show that the effect of $H_1^\pm$, $H_2^\pm$ and $H^{\pm\pm}$ can be as large $-10\% +4\%$ relative to the SM predictions. If, in addition, the modified Veltman conditions are also imposed, the effect of $H_1^\pm$, $H_2^\pm$ and $H^{\pm\pm}$ can be as large as $\pm2\%$ relative to the SM predictions.
The Cherenkov Telescope Array Observatory is the next generation ground-based telescope array to study very-high-energy electromagnetic radiation from the Universe. CTA will open a new era in this energy domain with its superior performance with respect to the current generation. In this talk, I will present the most important aspects of the very wide science case of CTA and I'll review fundamentals of the imaging Cherenkov approach. The prospects for the possible discoveries will be presented, with focus on the legacy surveys and on the fundamental astrophysics and physics to be targeted by the CTA Observatory. Our view of the very-high-energy sky is about to change dramatically, CTA will open a new era in our understanding of the highest energetic phenomena in the Universe and in this talk I will discuss some of the expected scientific output.
The Deep Underground Neutrino Experiment (DUNE) aims to precisely measure the long baseline neutrino oscillation parameters, for a definitive determination of the neutrino mass ordering and for searching for charge-parity violation in the leptonic sector.
DUNE will utilize the most intense, wide spectrum muon neutrino/anti-neutrino beam, produced at Fermilab, and a 70 kton liquid Argon Time Projection Chamber complex, working as Far Detector. The far detector will be located at the Sanford Underground Research Facility (SURF) in South Dakota, at 1300 km from the proton beam target.
To reduce the systematics dominated by the flux and cross-section uncertainties, a Near Detector complex made by three detectors, two of these movable off-axis, will be installed at Fermilab.
In this talk, I will briefly describe the DUNE physics program, the current design and technology, and the expected sensitivity on neutrino oscillation measurements.
Understanding the properties of nuclear matter and its emergence through the underlying partonic structure and dynamics of quarks and gluons requires a new experimental facility in hadronic physics known as the Electron-Ion Collider (EIC). The EIC will address some of the most profound questions concerning the emergence of nuclear properties by precisely imaging gluons and quarks inside protons and nuclei such as their distributions in space and momentum, their role in building the nucleon spin and the properties of gluons in nuclei at high energies. In January 2020 the EIC received CD-0 and Brookhaven National Laboratory was selected as site, and June 2021 CD-1. This presentation will give highlights on the EIC science program, introduce the experimental equipment and its integration into the accelerator and give the status of the EIC project, as well what are the next major steps.
The discovery of the Higgs boson marked the beginning of a new era in HEP. Precision measurement of the Higgs boson properties and exploring new physics beyond the Standard Model using Higgs as a tool become a natural next step beyond the LHC and HL-LHC. Among the proposed Higgs factories worldwide, the Circular Electron Positron Collider (CEPC) is proposed by the Chinese HEP community and to be hosted in China. The CEPC will be located in a tunnel with about 100km circumference. It will operate at CME of 240 GeV as a Higgs factory. It can also operate at lower energy as W and Z boson factory. In this talk, the overview and global aspects of the CEPC project, highlights of CEPC accelerator and detector R&D will be presented.
As one of the proposed Higgs factories, the CEPC collider will produce high statistics and clean data of Higgs, Z, and W bosons, potential top with upgradable plan, allowing us to perform unprecedented measurements of the SM and to explore BSM physics including dark matter and others, up to an energy scale of 10 TeV. In this talk, the recent studies on the precisions of measuring Higgs, W, Z, top as well as flavor physics with latest running plans are presented. The comparisons of the physics with HL-LHC and other Higgs factories such as Fcc-ee are addressed as well.
The proposed Compact Linear Collider (CLIC) will provide electron-positron collisions with centre-of-mass energy operation in three stages from a few hundred GeV up to 3 TeV. This offers a rich precision physics program combined with high sensitivity to a wide range of possible new phenomena. The precision required for such measurements and the specific conditions imposed by the beam bunch sizes and time structure put strict requirements on the detector design and technology development. This includes low-mass vertexing and tracking systems with small pixels, highly granular imaging calorimeters, and a precise hit-timing resolution for all subsystems.
A variety of detector optimisation studies have been carried out to establish the overall detector performance and to assess the impact of different technology options. In parallel, ambitious technology R&D programs are pursued, addressing the challenging CLIC detector requirements and exploiting synergies with other detector R&D projects. Several software and hardware tools have been developed as part of the R&D programme, enabling efficient simulation and testing of various technology demonstrators.
This contribution introduces the CLIC experimental conditions and detector requirements and presents the optimised CLICdet detector concept, followed by examples of the ongoing R&D activities for silicon pixel detectors.
The Compact Linear Collider (CLIC) is a proposed TeV-scale linear electron-positron collider based on a novel two-beam acceleration technique. With its high luminosity and a broad energy range, from 380 GeV to 3 TeV, CLIC presents a mature option for a future Higgs factory and discovery machine. Detailed studies of the CLIC physics potential based on a dedicated detector concept, CLICdet, profit from a comprehensive suite of software tools designed for physics analysis. This talk presents a general introduction to CLIC. Highlights of the CLIC physics studies will be reported, many of which rely on full simulation.
The clean environment at CLIC, its high collision energies and electron beam polarisation enable unprecedented precision in Higgs, electroweak and top quark studies. These measurements include Higgs self-coupling determination, constraining its invisible decays, studies of CP violation effects, and top-threshold scan. At high energy stages, CLIC offers promising prospects for Beyond the Standard Model physics searches. It provides both indirect sensitivity through the Effective Field Theory framework, probing extremely high new physics scales, and direct searches encompassing high-mass particles and diverse non-standard signatures. The presented studies show that CLIC surpasses the HL-LHC in its potential for precision measurements and is competitive in the exploration of many new physics scenarios.
Establishing a deep underground physics laboratory to study, amongst others, double beta decay, geoneutrinos, reactor neutrinos and dark matter has been discussed for more than a decade within the austral African physicists’ community. PAUL, Paarl Africa Underground Laboratory, is foreseen as an open international laboratory,inside the Huguenot Tunnel, which is located between the towns of Paarl and Worcerster in the Western Cape Province of South Africa. A progress report and the prospects of the initiative will be presented.
The near detector of T2K (ND280) is undergoing a major upgrade. A new scintillator tracker, named superFGD, with fine granularity and 3D-reconstruction capabilities has been assembled at J-PARC. The new Time Projection Chambers are under construction, based on the innovative resistive Micromegas technology and a field cage made of extremely thin composite walls. New scintillator panels with precise timing capability have been built to allow precise Time of Flight measurements.
The detector is currently in assembly phase following a detailed effort of characterization during detector production. The results of multiple tests of the detectors with charged beams, neutron beam, cosmics and X-rays will be presented. Among these results, we could mention the first measurement of neutron cross-section with the superFGD and the first detailed characterization of the charge spreading in resistive Micromegas detectors.
Thanks to such innovative technologies, the upgrade of ND280 will open a new way to look at neutrino interactions thanks to a significant improvement in phase space acceptance and resolution with an enhanced purity in the exclusive channels involving low-momentum protons, pions and neutrons. Sensitivity results and prospects of physics capabilities will be also shown.
The upcoming Hyper-Kamiokande experiment is the third generation of water Cherenkov detector situated in Kamioka, Japan, following in the footsteps of the highly successful Kamiokande and Super-Kamiokande experiments. Hyper-Kamiokande will serve as the far detector for a long-baseline neutrino experiment utilising the neutrino beam from J-PARC, with the primary purpose being the measurement of the CP violation phase, $\delta_{CP}$. With a fiducial volume approximately eight times larger than Super-K, it is also perfectly placed to observe neutrinos from astrophysical sources, as well as searching for proton decay. To make these measurements a reduction in systematic errors in comparison to current levels is required, towards which a range of calibration sources, a new detector, IWCD, and new techniques are currently being developed. This talk will describe the approaches being developed for detector calibration and the determination of systematic uncertainties and their impact on the sensitivity of Hyper-Kamiokande.
The first stage of the Future Circular Collider (FCC) will be an e+e- collider (FCC-ee) as successor to the Large Hadron Collider at CERN. The FCC-ee will enable a precise characterization of the Higgs boson together with electroweak, flavour, QCD, top precision physics, as well as searches beyond the Standard Model, with a real chance of discovery. Reaching experimental and theoretical systematic uncertainties commensurate to the statistical precision of the many measurements feasible at the FCC-ee requires careful preparation of the detector concepts, possibly of the mode of operation, and of theoretical developments.
The ambitious performance requirements for the four FCC-ee detectors (and the relevant technological options) are obtained from the evaluation of the sensitivity of several physics benchmark processes, by simulating variants of a number of detector concepts, such as CLD (CLIC-like detector) or IDEA (Innovative Detector for Electron-Positron Accelerators), including luminometer, vertex detector, central tracker, calorimeter(s), superconducting magnet, and muon detection system.
A solid software infrastructure is instrumental for the above mentioned evaluation. The FCC software ecosystem is tightly connected with Key4HEP, a turnkey software stack providing, in a ready-to-use way, all functionalities required by an HEP experiment, including a core software framework and tools for signal generation; parameterized, fast, and full simulation; reconstruction; and analysis. The Key4HEP project aims to provide an optimal synthesis of community products from LHC and beyond; it is the result of a common ongoing effort bringing together the future HEP projects communities. In this presentation, we will discuss the status of the Key4hep project with respect to the needs of the FCC Feasibility study, and the plans ahead.
The LHCb experiment is the dedicated flavour physics experiment at the LHC and is planning its second major upgrade during Long Shutdown 4 in the early 2030s to increase its instantaneous luminosity by about one order of magnitude. At the heart of this will be a new Vertex Locator, which will continue to provide precise spatial resolution for particles produced in the proton-proton collision region or as products of flavoured particle that fly a measurable distance before decaying. In addition, the sensors will have to provide precise timing information to help disentangle the many collisions happening in one proton-proton bunch crossing. A low material budget is required to minimise multiple scattering with the use of a non-vacuum-tight RF-shield being a promising and powerful factor, which however requires operation in ultra-high vacuum. Finally, the detector needs to be able to function in a radiation environment with a fluence as high as 6e16 1 MeV neq; corresponding to 2.4 Grad TID.
The ATLAS detector, a state-of-the-art particle detector, is uniquely situated
100 meters below the earth’s surface in the tunnel of the Large Hadron
Collider (LHC), extends 44 meters in length and 25 meters in height with an
estimated mass of 7000 tons, and provides 4π coverage in solid angle due to
its symmetric cylindrical design.
By 2029, the luminosity is expected to increase significantly, creating a
challenge due to the occurrence of pile-up - a phenomenon where multiple
collisions occur simultaneously with the primary collision of interest.
To address this, the High Granularity Timing Detector (HGTD) will be integrated
into the ATLAS detector. This addition will cover a pseudorapidity
range between 2.4 and 4.0 and is designed to provide a time resolution per
track of 30 ps for minimum-ionizing particles, which degrades to 50 ps towards
the end of HL-LHC operations. The upgrade will mitigate the adverse
effects of the pile-up and improve the reconstruction of forward objects. Furthermore,
HGTD provides exceptional capabilities for making measurements
of the luminosity, a key factor for precision physics measurements.
This presentation delves into the intricacies of monitoring three essential
components in the HGTD DAQ chain: the ALTIROC2, the lpGBT and
the VTRx+. Effective monitoring of these components is crucial to guarantee
operations, especially in light of voltage fluctuations that can adversely
impact the detector’s performance. The ADC of the lpGBT is utilized
for both the monitoring of the ALTIROC2, consisting of measurements
across various voltage levels such as Vgrnd, Vddd, Vdda. Furthermore,
the use of the ADC in the monitoring of the ALTIROC2 and the lpGBT ensures
proper conversion from analog to digital signals. Special emphasis is
also placed on monitoring the internal temperature sensors of the
ALTIROC2, the lpGBT and the VTRx+.
The increase of the particle flux (pile-up) at the HL-LHC with instantaneous luminosities up to L ≃ 7.5 × 10$^{34}$ cm$^{−2}$s$^{−1}$ will have a severe impact on the ATLAS detector reconstruction and trigger performance. The end-cap and forward region where the liquid Argon calorimeter has coarser granularity and the inner tracker has poorer momentum resolution will be particularly affected. A High Granularity Timing Detector (HGTD) will be installed in front of the LAr end-cap calorimeters for pile-up mitigation and luminosity measurement.
The HGTD is a novel detector introduced to augment the new all-silicon Inner Tracker in the pseudo-rapidity range from 2.4 to 4.0, adding the capability to measure charged-particle trajectories in time as well as space. Two silicon-sensor double-sided layers will provide precision timing information for minimum-ionizing particles with a resolution as good as 30 ps per track in order to assign each particle to the correct vertex. Readout cells have a size of 1.3 mm × 1.3 mm, leading to a highly granular detector with 3.7 million channels. Low Gain Avalanche Detectors (LGAD) technology has been chosen as it provides enough gain to reach the large signal over noise ratio needed.
To simulate the HGTD detector, a format based on XML has been used to define the descriptions of the detector. However, further refinement is required to align the geometry and material descriptions with the latest design of mechanical and electrical components, including related services outside the HGTD volume that may impact the overall performance of the ATLAS detector. In addition, to ensure the accuracy and reliability of the geometry implementation an automated validation procedure is implemented to continually assess the status of the geometry implementation in the ATLAS framework.
This talk presents an overview of the recent results from the LHCb experiment: CP violation and mixing in charm and beauty measurements, lepton flavour universality tests and lepton flavor violation, spectroscopy, electroweak measurements and searches for new physics.
The Muon g-2 endures as one of the most stringent tests of the Standard Model (SM). The recent combined result from Run 2 and Run 3 of the Muon g-2 Experiment at Fermilab confirms both the Run-1 Fermilab and Brookhaven measurements of the Muon g-2 with an overall unprecedented precision of 190 parts-per-billion, and it has already surpassed the overall target for its systematic uncertainty. The status of the SM prediction, also at sub-percent precision, rests on the determination of the hadronic vacuum polarisation (HVP) contributions. Tensions exist between data-driven dispersive evaluations and lattice QCD of the HVP, with the former favouring a signal of new physics at 5 sigma when comparing the SM prediction to the Muon g-2 Experiment, and the latter being in closer agreement with the experimental measurement. I will review both the status of the Muon g-2 Experiment (including projections for the release of its final result from its entire data set) and of the theoretical SM predictions, highlighting the efforts by the Muon g-2 Theory Initiative to resolve and understand current discrepancies.
The BESIII experiment, which is operated at the BEPCII electron-positron collider in Beijing since 2009, has collected world leading high statistic data samples in the tau-charm energy region. This offers unique possibilities to study exotic QCD states in the charmonium sector, but also the light meson spectrum which can be accessed via charmonium decays. The talk will discuss recent studies carried out by the BESIII experiment and their implications
The large top quark samples collected with the ATLAS experiment at the LHC have yielded measurements of the production cross section of unprecedented precision and in new kinematic regimes. They have also enabled new measurements of top quark properties that were previously inaccessible, enabled the observation of many rare top quark production processes predicted by the Standard Model and boosted searches for flavour- changing-neutral-current interactions of the top quark, that are heavily suppressed in the SM. In this contribution the highlights of the ATLAS top quark physics program are presented, as well as projections of the expected sensitivity after the High Luminosity phase of the LHC.
Recent highlights and future plans with ALICE at the LHC
Marielle Chartier$^1$ for the ALICE Collaboration
$^1$University of Liverpool, Oliver Lodge Laboratory, United Kingdom
ALICE (A Large Ion Collider Experiment) is one the four large experiments at the CERN Large Hadron Collider (LHC), whose research programme aims at an understanding of the phase equilibria of hadronic matter at extreme energy densities. The physics pursued with ALICE addresses the nature and origin of all visible matter in the universe, and how it can be described in terms of the fundamental, non-abelian, gauge-field theory, QCD.
ALICE is designed to detect, track, and identify hadrons, electrons, muons, and photons in proton-proton, proton-lead and lead-lead collisions at ultra-relativistic energies. In such heavy-ion collisions extremely large temperatures are generated, giving rise to an extended hadronic system with extreme energy density and very low baryon density. Over more than a decade, evidence has accrued that, at the energy scale of the LHC, this hadronic system is a deconfined phase of hadronic matter, the Quark-Gluon Plasma (QGP).
ALICE has just undergone substantial upgrades during the second long LHC shutdown (LS2). With its excellent particle identification capability, together with its substantially improved track and vertex reconstruction, and rate of data acquisition, ALICE is now in a position to accumulate 10 nb$^{−1}$ of Pb-Pb collisions during LHC Run 3 and Run 4. The topological scope and kinematic reach of new data with jets up to p$_T$ < 120 GeV/c, together with low transverse momentum (p$_T$) heavy-flavour (charm and beauty) particles, and low-mass, low-p$_T$, di-leptons are substantially extended with the upgraded ALICE detector.
This talk will focus on some highlights of recent results from ALICE and on the performance of the LS2 upgrades, as well as on plans for the medium and longer-term future.
The ALICE detector at the LHC is dedicated to the study of the properties of the hot and dense QCD matter (quark-gluon plasma) produced in nucleus-nucleus collisions at ultra-relativistic energies. The heavy flavor (charm and beauty) quarks, having large masses, are produced in hard-parton scatterings at the early stages of the collisions. Their measurements in pp collisions are an important test of perturbative Quantum Chromodynamics (pQCD) and a reference for measurements in p--Pb and Pb--Pb collision systems. Heavy-flavor measurements in Pb--Pb collisions enable studying the properties of the QGP medium by investigating the interaction of its constituents with the heavy quarks traversing it. Studies in p--Pb collisions allow us to disentangle cold nuclear effects.
This contribution presents an overview of recent ALICE results for open heavy flavors in pp, p--Pb, and Pb--Pb collision systems.
Quarkonia are bound states of charm or beauty quarks with their anti-particle. They have long being considered as unique probes of the quark-gluon plasma (QGP) that is formed in ultra-relativistic heavy-ion collisions. Heavy quarks are produced in the hard scattering processes occurring at the beginning of the collision, while the formation of the bound state is affected by the presence of the QGP, and provides valuable information on it.
In particular, the presence of a deconfined state results in color screening or dissociation mechanisms that suppress the formation of the bound state. On the other hand, the large amount of c-cbar pairs produced during the collision at LHC energies can result in a regeneration of charmonium states.
Quarkonia can also be produced in a well defined phase space region from photon-nucleus or photon-nucleon scattering, which are abundant in ultra-peripheral heavy-ion collisions, and can also occur in nucleus-nucleus collisions with nuclear overlap. In the latter, a measured yield of J/psi compatible with coherent photoproduction opens many questions on the nature of the coherence when the nucleus breaks up.
Comparison with measurements in small systems, such as proton-proton and proton-lead collisions, represent a baseline for interpreting heavy-ion results.
Besides serving as a reference, the measurements in small systems are important on their own since they shed light on the quarkonium production mechanism, that is not fully understood as it has an intrinsic non-perturbative scale.
Polarisation measurements both in small and large systems are particularly powerful to disentangle the different production mechanisms.
Finally, several measurements in high-multiplicity pp or p-Pb events have revealed striking similarities with heavy-ion collisions. In particular, collective effects are observed that can be explained in the presence of multi-parton interactions (MPIs).The measurement of double quarkonium production gives direct access to MPIs, while indirect information can be inferred by the study of the multiplicity dependent production or by the azimuthal correlations between quarkonia and hadrons produced in the same event.
In this talk, an overview of the most recent ALICE results on quarkonium production and polarisation in small and large collision systems will be provided. The comparison with the corresponding available theoretical calculations will be discussed.
The Majorana nature of the neutrino, i.e., whether it is its own antiparticle, remains an open problem in modern physics. The observation of Neutrinoless Double Beta Decay (0$\nu\beta\beta$), a hypothesized beyond Standard Model process, would conclusively establish the Majorana nature of neutrinos. It would also demonstrate lepton number violation and could provide insight into the absolute neutrino mass scale. Previous experimental searches for 0$\nu\beta\beta$ in $^{76}$Ge achieved the lowest background index and the best energy resolution of all 0$\nu\beta\beta$ searches. The next generation tonne-scale germanium experiment LEGEND (Large Enriched Germanium Experiment for Neutrinoless $\beta\beta$ Decay) combines the technologies and techniques from the GERDA and Majorana Demonstrator experiments. LEGEND-1000 has a goal background index of 10$^{-5}$ counts/(keV.kg.yr) and sensitivity to a decay half-life beyond 10$^{28}$ yr. In phase 1, LEGEND-200 will operate 200 kg of enriched detectors in the upgraded GERDA cryostat at LNGS, Italy. In a planned phase 2, LEGEND-1000 will operate 1000 kg of enriched detectors at a site that is yet to be finalized. Currently, LEGEND-200 is currently taking data with 142 kg of germanium detectors. In this talk, the status and scientific outlook of LEGEND will be presented, on behalf of the collaboration.
We discuss a new experiment based on the proposal [1] to observe for the first time the coherent elastic neutrino-atom scattering (CEνAS), using electron antineutrinos from tritium decay and a liquid He-4 target, and also to search neutrino electromagnetic properties [2], including the neutrino magnetic moment. The experiment is under preparation within the research program of the National Centre for Physics and Mathematics (NCPM) and the Branch of Lomonosov Moscow State University in Sarov (Russia). In CEνAS the neutrino scatters with the whole atom and the atomic electrons tend to screen the weak charge of the atomic nucleus as seen by the neutrino probe. With tritium neutrinos the interference between the He-4 nucleus and the electron cloud of the He atom produces a sharp dip in the recoil spectrum at atomic recoil energies of about 9 meV, reducing sizably the number of expected events with respect to the coherent elastic neutrino-nucleus scattering case. A low-background neutrino laboratory is being created at the NCPM with a record high-intensity tritium source of 10 MCi (1 kg) [3-5] and a 1-m$^3$ liquid He-4 detector operating at temperatures as low as few tens of mK. With the estimated sensitivity of this apparatus, it is possible to detect CEνAS for the first time and also to observe or to set an upper limit on the electron neutrino magnetic moment μν on the level of few×10$^{−13}\mu_B$ at 90% C.L. It is possible that the intensity of the tritium source can be increased up to 40 MCi (4 kg). We also develop a 4-kg Si detector operating at temperatures of few tens of mK and having the energy threshold as low as ∼10 eV or even ∼1 eV due to the Neganov-Trofimov-Luke effect. This detector will allow us to test the neutrino magnetic moment of the order of 10$^{−12}\mu_B$ by measuring elastic neutrino-electron scattering [4].
References
[1] M. Cadeddu, F. Dordei, C. Giunti, K. Kouzakov, E. Picciau, and A. Studenikin, Phys. Rev. D 100, 073014 (2019), arXiv:1907.03302 [hep-ph].
[2] C. Giunti and A. Studenikin, Rev. Mod. Phys. 87, 531 (2015), arXiv:1403.6344 [hep-ph].
[3] V. N. Trofimov, B. S. Neganov, and A. A. Yukhimchuk. Phys. Atom. Nuc. 61, 1271 (1998).
[4] B. S. Neganov et al., Phys. Atom. Nuc. 64, 1948 (2001).
[5] V. P. Martemyanov et al., Fusion Sci. Technol. 67, 535 (2015).
The ICARUS collaboration has employed the 760-ton T600 detector in a successful three-year physics run at the underground LNGS laboratory, performing a sensitive search for LSND-like anomalous $\nu_e$ appearance in the CERN Neutrino to Gran Sasso beam, which contributed to the constraints on the allowed neutrino oscillation parameters to a narrow region around 1 eV$^2$. After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. In 2020 the cryogenic commissioning began with detector cool down, liquid argon filling and recirculation. ICARUS then started its operation collecting the first neutrino events from the Booster Neutrino Beam (BNB) and the Neutrinos at the Main Injector (NuMI) beam off-axis, which were used to test the ICARUS event selection, reconstruction and analysis algorithms. ICARUS successfully completed its commissioning phase in June 2022, moving then to data taking for neutrino oscillation physics, aiming at first to either confirm or refute the claim by Neutrino-4 short-baseline reactor experiment. ICARUS will also perform measurements of neutrino cross sections with the NuMI beam and several Beyond Standard Model searches. After the first year of operations, ICARUS will jointly search for evidence of sterile neutrinos with the Short-Baseline Near Detector (SBND), within the Fermilab Short-Baseline Neutrino (SBN) program. In this presentation, preliminary technical results from the ICARUS data with the BNB and NuMI beams are presented both in terms of performance of all ICARUS subsystems and its capability to select and reconstruct neutrino events.
The Short-Baseline Near Detector (SBND) will be one of three Liquid Argon Time Projection Chamber (LArTPC) neutrino detectors positioned along the axis of the Booster Neutrino Beam (BNB) at Fermilab, as part of the Short-Baseline Neutrino (SBN) Program. The detector is anticipated to begin operation later this year. SBND is characterized by superb imaging capabilities and will record over a million neutrino interactions per year. Thanks to its unique combination of measurement resolution and statistics, SBND will carry out a rich program of neutrino interaction measurements and novel searches for physics beyond the Standard Model (BSM). It will enable the potential of the overall SBN sterile neutrino program by performing a precise characterization of the unoscillated event rate and constraining BNB flux and neutrino-argon cross-section systematic uncertainties. In this talk, the physics reach, current status, and future prospects of SBND are discussed.
Precise knowledge of how neutrinos interact with matter is essential for measuring neutrino oscillations in long-baseline experiments. At the T2K experiment, the near detector complex measures neutrino interactions to constrain cross section models for oscillation studies and characterises the beam flux. In addition, the near detector complex provides a separate platform for performing neutrino-nucleon cross section measurements. The composition and design of one of the near detectors, ND280, allows for a large variety of cross section measurements on different targets to be performed.
The most recent cross section measurements from the ND280 detector, together with an overview of the T2K measurement strategy, adopted to reduce the model dependence, will be presented. With increasing statistics, dedicated efforts are devoted to investigating rare or poorly studied interaction channels studied including electron neutrino, kaon and neutral current interactions. In this talk, the latest measurements of pion production will be shown. This includes measurements of transverse pion kinematics, and an improved analysis of the coherent pion production cross section which makes use of an anti-neutrino sample for the first time.
The Deep Underground Neutrino Experiment (DUNE) is a long-baseline neutrino oscillation experiment currently in construction and expected to take data in late 2020s. In order to explore a wide range of physics, from precise measurements of the neutrino oscillation parameters to proton decay and supernova neutrino detection, it will comprise a far detector complex located in the Sanford Underground Research Facility (USA), 1300 km from Fermilab where a muon (anti)neutrino beam will be produced.
In the first phase, the far detector complex will hold two 17 kTon detectors consisting of time-projection chambers (TPC) filled with liquid argon. When neutrinos interact with argon atoms, they create charged particles ionising the medium, where ionisation electrons can be collected along the trajectory by applying an electric field accross the TPC. Neutrino interaction also lead to the emission of photons, that can be collected with light detectors. This technology combining fine-grained tracking calorimetric and light information enables an accurate reconstruction of the charged particles created in neutrino interaction, to achieve a resolution at the millimeter scale.
While based on the same principle, the two detectors display difference in their design. The first detector, FD1-HD, contains a vertical cathod in the middle producing a horizontal electric field accelerating the ionisation electrons towards an anode made of wire planes. The second detector, FD2-VD, holds a horizontal cathod producing a vertical electric field accelerating the ionisation electrons towards an anode made of perforated printed circuit boards. Both also hold a photon-detection system located on the cathod and the walls.
In this talk, I will review the design of those two far detectors, the current status of the prototypes construction and analyses, as well as the next steps towards the completion of the DUNE experiment.
Searches for new physics are conducted in different experimental conditions, e.g. at high energy colliders or with high intensity particle beams. The Deep Underground Neutrino Experiment (DUNE) will be a powerful tool for the study of a variety of physics topics, due to its high-intensity proton beams that provide large neutrino fluxes, and which are sampled by a near detector system consisting of a combination of capable precision detectors, and by the very massive far detector system located deep underground.
Recently, such accelerator-based neutrino experiments have been recognised as excellent tools to search for new particles and unveil new interactions and symmetries beyond those predicted in the Standard Model (SM), including so-called feebly interacting particles (FIPs).
We will discuss DUNE’s sensitivities for a number of example processes such as to sterile neutrino mixing, heavy neutral leptons, non-standard interactions, CPT symmetry violation, Lorentz invariance violation, neutrino trident production, dark matter from both beam induced and cosmogenic sources, baryon number violation, and other new physics topics that complement those at high-energy colliders and extend the present reach.
The Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose neutrino experiment currently under construction in southern China.
The detector consists of a 35.4 m diameter acrylic sphere filled with 20 kton of ultra-pure liquid scintillator and makes JUNO the largest LS-based, underground neutrino observatory capable of addressing many important topics in different fields of neutrino physics. The primary goal of JUNO is to determine the neutrino mass ordering with a significance greater than 3σ after 6 years of data taking and to perform high-precision measurement of neutrino oscillation parameters. This will be achieved by exploiting the electron antineutrinos emitted by the Yangjiang and Taishan nuclear power plants located 53 km away from the experimental site, together with the precise measure of the reactor antineutrino energy spectrum provided by its satellite detector, the Taishan Antineutrino Observatory, located at about 30 m from a reactor core of the Taishan plant.
The JUNO central detector will be equipped with 17.612 20-inch and 25.600 3-inch photomultiplier tubes to provide a photocathode coverage of 78% and an energy resolution better than 3% at 1 MeV with an absolute energy scale uncertainty lower than 1%. The central detector hall will be filled with ultra-pure water to shield the environmental radioactivity and act as a water Cherenkov detector for cosmic muons tagging.
Thanks to its excellent characteristics in terms of an unprecedented active mass, excellent energy resolution and exceptional background control, the extensive physics program of JUNO comprises also solar neutrinos, atmospheric neutrinos, supernova neutrinos, and geo-neutrinos, as well as beyond Standard Model physics topics such as nucleon decay.
The detector construction is expected to be completed in 2024. In this talk, I will present the structure of the JUNO detector, its status, and the physics opportunities.
Core-collapse supernovae (CCSNe) play a significant role in our understanding of the Universe's dynamics. The time profile of neutrinos emitted during these supernovae offers valuable insights into the mechanism behind collapsing stars and the behavior of particles in extremely dense environments. The detection of neutrinos from the SN1987A supernova in the Large Magellanic Cloud marked a groundbreaking milestone in neutrino astronomy. However, due to the rarity of supernovae, no other observations of supernova neutrinos have been made thus far.
To maximize the information obtained from a galactic CCSN, it is essential to combine multiple experiments in real-time and transmit the data to telescopes. One notable example is the SNEWS system, which faces the challenge of promptly locating a supernova within minutes. Several methods are employed to measure the distance to the supernova, some of which rely on model- and distance- independent based observables. These observables depend on the accuracy of CCSN simulations and the neutrino flavor conversion mechanism. As an example, beyond the Standard Model mechanisms, such as neutrino decays, can potentially influence the accuracy of distance measurements by altering the neutrino flavor conversion process.
In this study, we propose a combination of model- and distance-independent observables from different experiments sensitive to various neutrino flavors: the DUNE experiment (sensitive to electronic neutrino flavors), the DarkSide detector (sensitive to all neutrino flavors equally), and water Cherenkov detectors (sensitive to anti-electronic neutrino flavors). This approach enables the identification of deviation in the flavor composition of observed neutrinos, providing valuable information about certain neutrino properties. The results obtained from this combined analysis will be incorporated into the SNEWS system, allowing for the correction of supernova distance measurements if necessary.
We present the results from the analysis of the down-going flux of nuclearites, based on data collected over a period of nine years (2009 to 2017) using the ANTARES neutrinos telescope. The results exhibit a remarkable enhancement compared to previously reported results. Notably, they represent the pioneering observation made by a neutrino telescope regarding nuclearites, setting the most stringent constraints ever recorded for these particles.
In this contribution we continue our studies [1,2] of neutrino oscillations in a magnetic field. We consider neutrino flavour and spin oscillations in a magnetic field within the formalism of wave packets. Decoherence effects due to the wave packets separation are studied. The coherence lengths for oscillations on both vacuum $\omega^{vac}_{ij} = \Delta m^2_{ij}/4E_\nu$ and magnetic frequencies $\omega^B_{i} = \mu_i B_{\perp}$ are calculated. It is shown that the coherence lengths for oscillations on magnetic frequencies are proportional to the cube of neutrino energy $E_\nu^3$. The considered decoherence effects are especially important for describing high-energy neutrino oscillations, since they propagate on kiloparsec scale and bigger. In particular, we show that interaction with a magnetic field can modify flavour composition of high-energy neutrinos measured by neutrino telescopes IceCube, Baikal-GVD and KM3NeT.
[1] A.Popov, A.Studenikin, Neutrino eigenstates and flavour, spin and spin-flavour oscillations in a constant magnetic field, Eur.Phys.J.C 79 (2019) 2, 144.
[2] A.Lichkunov, A.Popov, A.Studenikin, Three-flavour neutrino oscillations in a magnetic field, arXiv: 2207.12285 [hep-ph].
It is well-known that dense matter can strongly affect the neutrino moving through it. It has been recently realized that transversal matter motion can substantially change neutrino dynamics in some astrophysical settings and, in particular, leads to the appearance of spin oscillations (see [1] and references therein). In this work we investigate neutrino quantum sates in transversally moving matter with respect to the conserved spin observable (operator) introduced earlier [2]. As it was shown by us in [3] the relevant spin quantum numbers can change due to electromagnetic interaction mediated by neutrino magnetic moment leading to the effect of neutrino spin light. In the present paper we also continue our studies and discuss this possibility in some detail with focus on neutrino motion in transversal matter currents.
[1] P.Pustoshny, A.Studenikin, Neutrino spin and spin-flavour oscillations in transversal matter currents with standard and non-standard interactions. Phys. Rev. D 98 (2018) 113009 (14 p.).
[2] A. Grigoriev, A. Studenikin, A. Ternov, Neutrino spin operator and dispersion in moving matter, Eur.Phys.J.C 82 (2022) 287.
[3] A. Grigoriev, A. Lokhov, A. Studenikin, A. Ternov, Spin light of neutrino in astrophysical environments, J. Cosmol. Astropart. Phys. (2017) 068P_0517 (23 p.).
The entropy of von-Neumann can be computed directly by describing the density matrix of the associated system. For black holes however, it is rather difficult to evaluate this entropy because before all else we must have a quantum formulation of this gravitational system. We outline the derivation of a gravitational fine-grained entropy using a quantum extremal surface that extremizes the generalized entropy, i.e., the sum of area and bulk entanglement entropy, following the Page curve. We illustrate this formulation for the AdS/CFT case and calculate the corresponding fine-grained entropy.
Abstract pdf file attachement
In this work, we study a model of holographic dark energy using FLRW cosmology in the context of modified gravity. An extension of the symmetric teleparallel gravity is obtained by considering the gravitational action $L$ is given by an arbitrary function $f$ of the non-metricity $Q$, where the nonmetricity Q is responsible for the gravitational interaction, and of the trace of the matter-energy-momentum tensor $T$,so that $L=f(Q,T)$. We govern the features of the derived cosmological model in view of the relation between cosmic time and redshift as $t(z)=\frac{kt_{0}}{b}f(z)$ where $f(z)=W\left [ \frac{b}{k}e^{\frac{b-ln(1+z)}{k}} \right ]$ and $W$ denotes the Lambert function, and discuss the evolution trajectories of the equation of state parameter and stability parameters in the evolving universe.
An overview of recent results from the CMS experiment will be presented along with the preparation and upgrade of the CMS experiment for the HL-LHC.
Motivated by the recent search for bbτ τ final state conducted by the CMS experiment, we would like to address the study of signal and background for such a final state within the so-called 2HDM Type-I. We investigate the scope of the LHC in accessing the process gg → H → hh → b b τ τ by performing a Monte Carlo (MC) analysis aimed at extracting this signal from the SM backgrounds, in the presence of a dedicated trigger choice and kinematical selection. We prove that some sensitivity to such a channel exists already at Run 3 of the LHC while the High-Luminosity LHC (HL-LHC) will be able to either confirm or disprove this theoretical scenario over sizable regions of its parameter space.
In the Standard Model, the ground state of the Higgs field is not found at zero but instead corresponds to one of the degenerate solutions minimising the Higgs potential. In turn, this spontaneous electroweak symmetry breaking provides a mechanism for the mass generation of nearly all fundamental particles. The Standard Model makes a definite prediction for the Higgs boson self-coupling and thereby the shape of the Higgs potential. Experimentally, both can be probed through the production of Higgs boson pairs (HH), a rare process that presently receives a lot of attention at the LHC. In this talk, the latest HH searches by the ATLAS experiment are reported, with emphasis on the results obtained with the full LHC Run 2 dataset at 13 TeV. Non-resonant HH search results are interpreted both in terms of sensitivity to the Standard Model and as limits on the Higgs boson self-coupling and the quartic VVHH coupling. Further, HH searches can be exploited to put constraints on the Wilson coefficients of Effective Field Theories. The Higgs boson self-coupling can be also constrained by exploiting higher-order electroweak corrections to single Higgs boson production. A combined measurement of both results yields the overall highest precision, and reduces model dependence by allowing for the simultaneous determination of the single Higgs boson couplings. Results for this combined measurement are also presented. Finally, extrapolations of recent HH results towards the High Luminosity LHC upgrade are also discussed.
Future e$^+$e$^-$ colliders, thanks to their clean environment and triggerless operation, offer a unique opportunity to search for long-lived particles (LLPs) at sub-TeV energies. Considered in this contribution are promissing prospects for LLP searches offered by the International Large Detector (ILD), with a Time Projection Chamber (TPC) as the core of its tracking systems, providing almost continuous tracking. The ILD has been developed as a detector concept for the ILC, however, studies directed towards understanding of ILD performance at other collider concepts are ongoing.
Based on the full detector simulation, we study the possibility of reconstructing decays of both light and heavy LLPs at the ILD. For the heavy, $\mathcal{O}$(100 GeV) LLPs, we consider a challenging scenario with small mass splitting between LLP and the dark matter candidate, resulting in only a very soft displaced track pair in the final state, not pointing to the interaction point. We account for the soft beam-induced background (from measurable e$^+$e$^-$ pairs and $\gamma\gamma\to$ hadrons processes), expected to give the dominant background contribution due to a very high cross section, and show the possible means of its reduction. As the opposite extreme scenario we consider the production of light, $\mathcal{O}$(1 GeV) pseudo-scalar LLP, which decays to two highly boosted and almost colinear displaced tracks.
We also present the corresponding results for an alternative ILD design, where the TPC is replaced by a silicon tracker modified from the Compact Linear Collider detector (CLICdet) design.
Search for new physics Beyond Standard Model (BSM) is one of the major goals of the CMS experiments at the LHC. A variety of BSM searches including exotic signatures, narrow resonances such as W' and Z' particles decaying to final states with top quarks and Higgs boson is presented. The results are based on proton-proton collision data collected during Run 2 of the LHC at a centre-of-mass energy of 13 TeV and recorded with the CMS detector.
An overview of the latest results from the NA62 experiment at CERN will be presented.
The NA62 experiment collected the world's largest dataset of charged kaon decays in 2016-2018, leading to the first measurement of the branching ratio of the ultra-rare $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay, based on 20 candidates. This provides evidence for the very rare $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay, observed with a significance of 3.4$\sigma$. This measurement is also used to set limits on BR($K^+ \rightarrow \pi^+ X$), where X is a scalar or pseudo-scalar particle. The analysis of the full 2016-2018 data sample and future NA62 plans and prospects are reviewed.
Rare kaon decays are among the most sensitive probes of both heavy and light new physics beyond the Standard Model description thanks to high precision of the Standard Model predictions, availability of very large datasets, and the relatively simple decay topologies. The NA62 experiment at CERN is a multi-purpose high-intensity kaon decay experiment, and carries out a broad rare-decay and hidden-sector physics programme. Recent NA62 results on searches for violation of lepton flavour and lepton number in kaon decays, and searches for production of hidden-sector mediators in kaon decays, are presented. Future prospects of these searches are discussed. Searches for visible decays of exotic mediators from data taken in beam-dump" mode with the NA62 experiment are also reported. The NA62 experiment can be run as a
beam-dump experiment" by removing the kaon production target and moving the upstream collimators into a ``closed" position. More than $10^{17}$ protons on target have been collected in this way during a week-long data-taking campaign by the NA62 experiment. We report on new results from analysis of this data, with a particular emphasis on Dark Photon and Axion-like particle Models.
Following the recent update measurement of the W boson mass performed by the CDF-II experiment at Fermilab which indicates 7σ deviation from the SM prediction. As a consequence, the open question is whether there are extensions of the SM that can carry such a remarkable deviation or what phenomenological repercussions this has. In this paper, we investigate what the theoretical constraints reveal about the 123-model. Also, we study the consistency of a CDF W boson mass measurement with the 123-model expectations, taking into account theoretical and experimental constraints. Both fit results of S and T parameters before and after m CDF W measurement are, moreover, considered in this study. Under these conditions, we found that the 123-model prediction is consistent with the measured m CDF at a 95% Confidence Level (CL).
While experimental data has not ruled out the possibility of additional Higgs bosons or gauge sectors, several alternative models have been proposed to go beyond the standard model and tackle the question of hierarchy. These models predict the existence of heavy vector-like partner quarks that exhibit vector-axial (V-A) coupling, typically on the TeV scale. In this work, we use simplified interactions to establish the fundamental components of the model and explore potential scenarios beyond the standard model. We focus on the unusual decays of the partner heavy quark, called $T$, into $H^\pm b$, which may compete with $W^\pm b$ decays and create a new discovery channel at the Large Hadron Collider (LHC). Using Monte Carlo (MC) simulations, we analyse the signal-to-noise ratio of $pp\to qg\to T^{+}b\bar{b}j\to H^{+}b\bar{b}j\to W^{+}b\bar{b}j\to 1\ell+4b+1j+\slashed E_T$, and evaluate the sensitivity of the LHC to the masses of $T$ and $H^\pm$ in the two-Higgs-doublet model (2HDM) plus the vector-like quark (VLQ) model with a branching ratio of $100\%$ for $T\to H^\pm b$. We take into account current and predicted luminosities, as well as theoretical and experimental bounds. This paper presents a new strategy for identifying VLQs at the LHC, which goes beyond the usual search strategies that rely on decays of $T$ into Standard Model bosons.
In light of the recent deviation in the W boson mass measurement from the CDF-II, which significantly strays from the Standard Model (SM) prediction, our paper explores the implications of this within the framework of the Two-Higgs Doublet Model (2HDM). We focus on the scenario where the heavy CP-even H is recognized as the Higgs boson observed at 125 GeV.
Our analysis, which incorporates both theoretical and current experimental constraints along with the new CDF measurement, suggests that the 2HDM parameter space can offer a substantial adjustment. This adjustment aligns the predicted W mass more closely with the new CDF $M_W$ measurement.
Our study also reveals that the equality $M_{H^\pm} = M_A$ is not supported, and there is a positive splitting between the charged Higgs boson and all other states. Additionally, we delve into the influence on the effective mixing angle $\sin^2 θ_eff$ and the potential effects on the decays of the charged Higgs and CP-odd Higgs boson in the context of 2HDM type-I and type-X.
Most of the current experimental searches for charged Higgs bosons at the Large Hadron Collider (LHC) concentrate upon the $tb$ and $\tau\nu$ decay channels. In this study, we analyze the feasibility of the bosonic decay channel $W^{\pm (*)} h$ instead, with the charged gauge boson being either on-shell or off-shell and $h$ being a neutral light Higgs boson. Focusing on the Two-Higgs Doublet Model (2HDM), we consider the associated production of a charged Higgs with such a light neutral one, $pp\to H^\pm h$, at the LHC followed by the aforementioned charged Higgs boson decay, which leads to various signatures. We specifically study the $W^{\pm (*)}+ 4b/4\gamma$ final states and provide several Benchmark Points (BPs) for Monte Carlo (MC) analysis. We prove that there is a strong possibility that these signals could be found at the LHC with the centre of mass energy of 14 TeV and luminosity of 300 $\rm{fb}^{-1}$.
The aim of this study is to examine the impact of the Z+photon and Di-photon signal strength measurements, $\mu_{\gamma\gamma}$ and $u_{\gamma Z}$, on the allowed parameter space of the Inert Doublet Model (IDM). Specifically, we focus on the effect of these measurements on the second doublet mass $\mu_2^2$, and also their compatibility with the most recent constraint from the XENON1T experiment on the spin-independent DM-nucleon scattering cross-section. Similarly, the impact of IDM new physics, including the presence of embedded Higgs bosons ($S$, $A$, and $H^\pm$), on the trilinear Higgs coupling ($hhh$) has been thoroughly examined through a comprehensive study of one-loop radiative corrections.