FASER\nu is a newly proposed experiment which will take data
in run III of the LHC during 2021-2023. It will be located in front of
the FASER detector, 480~m away from the ATLAS interaction point in the
forward direction. Its main goal is to detect neutrinos of all flavors
produced at the interaction point with superb precision in
reconstructing charged tracks. This capability makes FASER\nu an
ideal setup for uncovering the pattern and properties of a light dark
sector. We demonstrate this capability for a well-motivated class of
models with a dark matter candidate of mass around a few GeV. Dark
matter annihilates to a pair of intermediate neutral particles that
subsequently decay into the standard model charged fermions. We show
how FASER\nuν can shed light on the structure of the dark sector by
unravelling the decay chain within such models.
in run III of the LHC during 2021-2023. It will be located in front of
the FASER detector, 480~m away from the ATLAS interaction point in the
forward direction. Its main goal is to detect neutrinos of all flavors
produced at the interaction point with superb precision in
reconstructing charged tracks. This capability makes FASER\nu an
ideal setup for uncovering the pattern and properties of a light dark
sector. We demonstrate this capability for a well-motivated class of
models with a dark matter candidate of mass around a few GeV. Dark
matter annihilates to a pair of intermediate neutral particles that
subsequently decay into the standard model charged fermions. We show
how FASER\nuν can shed light on the structure of the dark sector by
unravelling the decay chain within such models.