Correlating neutrino magnetic moment and scalar triplet dark matter to enlighten XENONnT bounds in a type II radiative seesaw model

We investigate neutrino magnetic moment, triplet scalar dark matter in a type II radiative seesaw scenario. With three vectorlike fermion doublets and two scalar triplets, we provide a loop level setup for the electromagnetic vertex of neutrinos. All the scalar multiplet components constitute the total dark matter abundance of the Universe and also their scattering cross section with detector lie below the experimental upper limit. Using the consistent parameter space in dark matter domain, we obtain light neutrino mass in sub-eV scale and also magnetic moment in the desired range. We further derive the constraints on neutrino transition magnetic moments, consistent with the XENONnT limit.

Figure 1

Effective electromagnetic vertex, where $q=p-p^{\prime }$.

Figure 2

One-loop Feynman diagram for transition magnetic moment.

Figure 3

One-loop diagram give rise to light neutrino mass.

Figure 4

Left panel depicts the SI DM-nucleon cross section for the data (cyan) that satisfies Planck limit on relic density. Horizontal dashed line corresponds to LUX-ZEPLIN bound [46]. Various colored data points of red and green satisfy neutrino magnetic moment and mass for specific set of values for $M_{\psi }$, shown in the right panel.

Figure 5

Allowed region of Yukawa with dark matter mass for two set of values for $M_{\psi }$ in the left panel. Right panel provides the favorable region for mass splittings, where the thick bands correspond to ${\delta }_{\mathrm{CR}}$ and thin bands indicate $\delta$.

Figure 6

Contribution of various annihilation and coannihilation channels for high (upper panel) and low (lower panel) values of mass splitting $\delta$.

Figure 7

Top left panel displays relic density as a function of dark matter mass, illustrating the impact of $\delta$, with horizontal dashed lines corresponding to Planck bound [26]. Top right panel shows the parameter space consistent with aspects related to DM and neutrino in $M_{R1}-\delta$ plane. Lower panel projects the mass splitting of $CP$-even mass eigenstates with $CP$-odd scalar.

Figure 8

Relevant annihilation channels contributing to relic density (classified based on output particles), where $f$ stands for SM fermions, $f^{\prime \prime \prime }$ represents SM quarks and leptons except neutrinos and $i=1,2$.

Figure 9

Relevant coannihilation channels contributing to relic density, where $f=u,c,t,e,\mu ,\tau$, $f^{\prime }=d,s,b,{\nu }_e,{\nu }_{\mu },{\nu }_{\tau }$ and $i$, $j=1,2$.

Figure 10

Oblique parameters computed for the parameter space consistent with dark matter and neutrino aspects. Horizontal dashed lines correspond to $1\sigma$ region of the current bounds from PDG [49].

Figure 11

Left panel projects bounds on transition and effective magnetic moment, right panel shows the allowed region of transition magnetic moments in 90% and 99% C.L. for one degree of freedom at XENONnT experiment.