Constraining the transitional magnetic dipole moment interaction between active and heavy neutrinos with the $$Z'$$ at FASER$$\nu $$

Abstract

AbstractWe investigate the effects of the transitional magnetic dipole type interactions of the active-to-heavy-neutrino associated with a new neutral gauge boson $$Z'$$ Z ′ on neutrino-nucleon scattering at the ForwArd Search ExpeRiment-$$\nu $$ ν (FASER$$\nu $$ ν ). We consider the neutral-current neutrino-nucleon scattering ($$\nu A\rightarrow N A'$$ ν A → N A ′ , where $$A'$$ A ′ denotes the disintegrated nuclei) as the production mechanism of the heavy neutrino N at FASER$$\nu $$ ν and estimate the sensitivity reach on the magnetic-type dipole coupling $$\omega _{\nu _\alpha }$$ ω ν α for a range of heavy neutrino mass ($$1\,\textrm{GeV}< \textrm{M}_{\textrm{N}} < 70 \mathrm{~GeV}$$ 1 GeV < M N < 70 GeV ). In this study, we consider three benchmark models, in which the heavy neutrino is coupled to $$L_e$$ L e , $$L_\mu $$ L μ or $$L_\tau $$ L τ doublet, respectively.