Projected sensitivities of the LUX-ZEPLIN (LZ) experiment to new physics
  via low-energy electron recoils
  LUX-ZEPLIN (LZ) is a dark matter detector expected to obtain world-leading
sensitivity to weakly interacting massive particles (WIMPs) interacting via
nuclear recoils with a ~7-tonne xenon target mass. This manuscript presents
sensitivity projections to several low-energy signals of the complementary
electron recoil signal type: 1) an effective neutrino magnetic moment and 2) an
effective neutrino millicharge, both for pp-chain solar neutrinos, 3) an axion
flux generated by the Sun, 4) axion-like particles forming the galactic dark
matter, 5) hidden photons, 6) mirror dark matter, and 7) leptophilic dark
matter. World-leading sensitivities are expected in each case, a result of the
large 5.6t 1000d exposure and low expected rate of electron recoil backgrounds
in the $<$100keV energy regime. A consistent signal generation, background
model and profile-likelihood analysis framework is used throughout.
