Phenomenological implications of sterile neutrinos in the $\mu \nu$SSM and dark matter

PAULINA KNEES, DANIEL E. LOPEZ -FOGLIANI, CARLOS MUÑOZ

ASTROPARTICLE PHYSICS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2023 vol. 2023 p. 1 - 24

0927-6505

We analyze the role of sterile neutrinos in the framework of the $mu nu$SSM, where the presence of right-handed neutrinos provides a simultaneous solution to $mu$- and $nu$-problems in supersymmetry. We adopt a minimalistic approach, reproducing light neutrino masses andmixing angles at tree-level using just two right-handed neutrinos aspart of the seesaw mechanism. A third right-handed neutrino does notcontribute significantly to the mass of the three active ones,behaving as a sterile neutrino with a mass in the range keV−MeV.Furthermore, a sterile neutrino of about 10 keV can be a goodcandidate for dark matter with a lifetime larger than the age of the Universe. In particular, the three-body decay to active neutrinos gives the dominant contribution to its lifetime. The one-loop decayto gamma and active neutrino is subdominant, but relevant forobservations such as astrophysical X-rays. We find regions of the parameter space of the $mu nu$SSM, with different values of the sterileneutrino mass, fulfilling not only these constraints but alsocollider constraints from the Higgs sector.p { margin-bottom: 0.25cm; line-height: 120%; background: transparent }a:link { color: #000080; so-language: zxx; text-decoration: underline }