Inert Higgs Dark Matter for New CDF W-boson Mass and Detection Prospects
  The $W$-boson mass, which was recently measured at FermiLab, suggests the
presence of new multiplets beyond the Standard Model (SM). One of the minimal
extensions of the SM is to introduce an additional scalar doublet, in which the
non-SM scalars can enhance $W$-boson mass via the loop corrections. On the
other hand, with a proper discrete symmetry, the lightest new scalar in the
doublet can be stable and play the role of dark matter particle. We show that
the inert two Higgs doublet model can naturally handle the new $W$-boson mass
without violating other constraints, and the preferred dark matter mass is
between $54$ and $74$ GeV. We identify three feasible parameter regions for the
thermal relic density: the $SA$ co-annihilation, the Higgs resonance, and the
$SS \to WW^*$ annihilation. We find that the first region can be fully tested
by the HL-LHC, the second region will be tightly constrained by direct
detection experiments, and the third region could yield detectable GeV
gamma-ray and antiproton signals in the Galaxy that may have been observed by
Fermi-LAT and AMS-02.
