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arXiv · 2305.08665

First Physics Results from the FASER Experiment

Brian Petersen
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Abstract

FASER is a new LHC experiment designed to search for light, weakly-interacting particles that are produced in proton-proton collisions at the ATLAS interaction point and travel in the far-forward direction. The first physics results from the initial year of data-taking are presented. A search for dark photons decaying to an electron-positron pair found no events, yielding new constraints on dark photons with couplings $\epsilon \sim 10^{-5} - 10^{-4}$ and masses $\sim 10$ MeV $- 100$ MeV. A search for muon-neutrino charged-current interactions in a tungsten target at the front of the FASER experiment found $153^{+12}_{-13}$ neutrino candidates with a negligible background. The reconstructed charge and momentum distributions imply the observation of both neutrinos and anti-neutrinos with an incident neutrino energy above 200 GeV.

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Brian Petersen. 2023-05-15. First Physics Results from the FASER Experiment. https://arxiv.org/abs/2305.08665

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