Speaker
Description
We conduct a combined analysis to investigate DM with hypercharge
anapole moments, focusing on scenarios of a spin-1/2 or 1 Majorana
DM particle interacting with SM particles through hypercharge
anapole interactions. For completeness, we construct general,
effective, and hypercharge gauge-invariant three-point vertices for the
interactions of a virtual photon or Z with with two identical massive
Majorana particles of any non-zero spin, after EWSB. We calculate the
relic abundance, analyze current constraints and future sensitivities
from the XENON$n$T DM direct detection and LHC (HL-LHC)
experiments, and apply the conceptual naive perturbativity bound
(NPB). Our findings demonstrate that the scenario with spin-1 DM is
more tightly constrained than that with spin-1/2 DM, due to the
reduced annihilation cross-section and/or the enhanced rate of LHC
mono-jet events. The spin-1 scenario can be almost entirely tested
after the full run of the HL-LHC, with the exception of a very small
parameter region. Our estimations anticipate even stronger bounds for
Majorana dark matter with higher spins.
