A new purpose for the $W$-boson mass measurement: searching for New Physics in lepton+$MET$

• DOI: 10.48550/arxiv.2310.13687
• Publication Date: 2023-01-01
• Authors: Kaustubh Agashe; Sagar Airen; Roberto Franceschini; Doojin Kim; A. Kotwal; Lorenzo Ricci; Deepak Sathyan
• Keywords: High Energy Physics - Phenomenology; High Energy Physics - Experiment (hep-ex); High Energy Physics - Phenomenology (hep-ph); Physics; QC1-999; FOS: Physical sciences; High Energy Physics - Experiment

We show that the $m_W$ measurement is a direct probe of New Physics (NP) contributing to lepton and missing transverse momentum ($\ell+MET$), independently from indirect tests via electroweak fit. Such NP modifies kinematic distributions used extract $m_W$, necessitating simultaneous fit NP. This effect can in principle bias measurement, but only limited extent for our considered models. Given that, we demonstrate agreement at high-precision with SM-predicted shapes results bounds competitive to, if not exceeding, existing ones two examples: anomalous $W$ decay involving $L_{\mu} - L_{\tau}$ gauge boson $\tilde{\nu}_{l} \tilde{l}$ production MSSM.