Indirect detection constraints on the scotogenic dark matter model

Abstract

Radiative seesaw models have the attractive property of providing dark matter candidates in addition to the generation of neutrino masses. Here we present a study of neutrino signals from the annihilation of dark matter particles that have been gravitationally captured in the Sun in the framework of the scotogenic model. We compute expected event rates in the IceCube detector in its 86-string configuration. As fermionic dark matter does not scatter off nucleons due to its singlet nature and therefore does not accumulate in the Sun, we study the case of scalar dark matter with a scan over the parameter space. Due to a naturally small mass splitting between the two neutral scalar components, inelastic scattering processes with nucleons can occur. We find that for most of the parameter space, i.e. for mass splittings below 500 keV, inelastic scattering in the Sun yields IceCube event rates above 10 events per year, whereas direct detection on Earth is sensitive only to 250 keV. Consequently, a detailed analysis with IceCube could lead to a lower limit on the scalar coupling λ 5 1.6 • 10 −5 • m DM /TeV. For larger mass splittings, only elastic scattering occurs in the Sun. In this case, XENON1T limits only allow for models with expected event rates of up to O(0.1) per year. Some of these models, in particular those with large DM mass and fermion coannihilation, could also be tested with a dedicated IceCube analysis of DM annihilation in the Galactic Center.

Temperature effects on the $Z_2$ symmetry breaking in the scotogenic model

“…The initial values should generate a valid electroweak minimum, i.e. fulfil the conditions (7). Also, we only considered points that satisfy the bounded from below conditions (8) at every step of the RGE running.…”

“…Due to its economic structure the scotogenic model has been studied in many publications in the literature. Both DM candidates, the lightest N 1 [3] and the the neutral component of η [4], can give a relic density consistent with DM abundance in viable parts of parameter space, while respecting bounds from direct [5,6] and indirect [7,8] detection.…”

Revisiting the scotogenic model with scalar dark matter

“…Indirect detection constraints in the scotogenic model for scalar DM masses below 500 GeV where previously considered in reference [26]. Neutrino signals from the annihilation of DM in the scotogenic scenario with scalar DM were studied recently in [50]. Here we study current constraints from indirect detection search focusing on the mass region between 100-700 GeV (where our benchmarks in table 4 lie).…”