Speaker
Description
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.
