arXiv subjects

Kunal Pandey

Publications and source records attributed to Kunal Pandey.

3 recordsLinked to original sources

arXiv2026

Light neutrinos, Dark matter and leptogenesis near electroweak scale and $Z_4$ symmetry

Considering $Z_4$ symmetry in Type I seesaw scenario, one could obtain mass-squared differences of light neutrinos, mixings and $CP$ violating phase within $3 \sigma$ confidence level based on neutrino oscillation data. This is possible with only three independent complex parameters for allowed Yukawa couplings and one real mass parameter for heavy right handed neutrino fields around electroweak scale. After considering only three more real parameters as coming from small soft-symmetry breaking terms, the lightest right handed neutrino could be considered as dark matter candidate via freeze-in mechanism and the other two heavier right handed neutrinos through their decays, could generate the baryonic asymmetry of the universe naturally via resonant leptogenesis.

hep-ph↗

arXiv2025

Sterile neutrino dark matter from a TeV Scale Seesaw

In this article, we investigate the phenomenological aspects of a feebly interacting sterile neutrino dark matter candidate within a low-scale seesaw framework. The Type-I seesaw model is augmented by a second complex scalar doublet ($\Phi_{\nu}$), which couples exclusively to the heavy right-handed neutrinos and the lepton doublet, thereby generating the neutrino Dirac mass term while the first scalar doublet is responsible for giving mass to the remaining Standard Model particles. The lightest sterile neutrino ($N_1$) acts as a feebly interacting massive particle (FIMP), produced via decays of $W^\pm$, $Z$ and extra scalars present in the setup. We point out that $W^\pm$ and $Z$ contributions were overlooked in the previous studies, which actually dominate the $N_1$ production by a factor of $\sim 10^{13}$ and solely determines the relic abundance. Incorporating them leads to several novel consequences for the DM phenomenology like a new non-thermal condition which leads to smaller Yukawa couplings. We thoroughly discuss about the enhancement possibilities of $N_1$'s mass which is controlled by the small vacuum expectation value ($v_{\nu}$) of the second Higgs doublet. After incorporating the latest Lyman-$\alpha$ forest observations, this setup can accommodate both warm and cold dark matter scenarios.

hep-ph↗

arXiv2024

Type I seesaw mechanism at TeV scale or below with minimal fields

A novel scenario is presented within the Type-I seesaw mechanism in which no other beyond Standard Model fields except three heavy right handed neutrinos, have been considered. Light neutrino masses around sub eV scale, could be possible at low seesaw scale around TeV or even below that. At the leading order, 6x6 seesaw mass matrix reproduces three massless neutrinos. The Dirac mass matrix with one loop corrections, breaks that massless texture and it is possible to get massive neutrinos. We have obtained the expression of mixing and Dirac CP violating phase for light neutrino mass matrix with one loop corrections. Only unknown parameters are the Yukawa couplings related to right handed neutrinos and their masses. These parameters satisfy the ATLAS, CMS experimental constraints.

hep-ph↗