Inelastic Fermion Dark Matter Origin of XENON1T Excess with Muon $(g-2)$
  and Light Neutrino Mass
  Motivated by the recently reported excess in electron recoil events by the
XENON1T collaboration, we propose an inelastic fermion dark matter (DM)
scenario within the framework of a gauged $L_{\mu}-L_{\tau}$ extension of the
standard model which can also accommodate tiny neutrino masses as well as
anomalous muon magnetic moment $(g-2)_{\mu}$. A Dirac fermion DM, naturally
stabilised due to its chosen gauge charge, is split into two pseudo-Dirac mass
eigenstates due to Majorana mass term induced by singlet scalar which also
takes part in generating right handed neutrino masses responsible for type I
seesaw origin of light neutrino masses. The inelastic down scattering of
heavier DM component can give rise to the XENON1T excess for keV scale mass
splitting with lighter DM component. We fit our model with XENON1T data and
also find the final parameter space by using bounds from $(g-2)_{\mu}$, DM
relic, lifetime of heavier DM, inelastic DM-electron scattering rate, neutrino
trident production rate as well as other flavour physics, astrophysical and
cosmological observations. A tiny parameter space consistent with all these
bounds and requirements will face further scrutiny in near future experiments
operating at different frontiers.
