Searching for Fundamental Novel Physics in CDF-II W Boson Mass Anomaly

The CDF-II collaboration’s recent high-precision measurement of W boson mass, \(m_W^\textrm{CDF} = 80.4335 \pm 0.0094\) GeV, indicates 7- \(\sigma \) deviation from the SM expectation \(m_W^\textrm{SM} = 80.354 \pm 0.007 \text {GeV}\) . This leads us to investigate the extension of SM, which can account for the aforementioned problems with SM. We investigate the possibility of the well-known canonical Scotogenic model, where dark matter particle running in the loop generates neutrino masses to explain the CDF-II measurement. For both scalar and fermionic dark matter possibilities, we simultaneously examine the constraints coming from a) neutrino mass, oscillation, neutrinoless double beta decay and lepton flavour violation experiments, b) from dark matter relic density and direct detection experiments, c) from LEP and ATLAS, d) from the oblique S, T, and U parameter values consistent with CDF-II W boson measurement. We demonstrate that the new CDF-II measurement rules out the feasible parameter space of the scalar dark matter in the high mass regions ( \(M_{\eta _{R}} \gtrsim 500~\text {GeV}\) ) while still allowing the intermediate mass regions \(54~\text {GeV} \lesssim M_{\eta _{R}} \lesssim 76~\text {GeV}\) . We also showed that the fermionic dark matter candidate in the canonical Scotogenic model, in the range \(M_{N_{1}} \lesssim 500~\text {GeV} \) , can satisfy CDF-II anomaly. In our second work, we focused on \(U(1)_{B-L}\) gauged SM extension. We demonstrate that \(B-L\) extended models can explain the revised best-fit values for S, T, and U following the CDF-II results. We studied the parameter space of models with and without mixing between neutral gauge bosons. We also reviewed the dark matter constraints and demonstrated that parameter space is compatible with current W boson mass, relic abundance, and direct detection experiments.