Neutrino meets ultralight dark matter: 0νββ decay and cosmology

Abstract

We explore the neutrinoless double beta (0νββ) decay induced by an ultralight dark matter field coupled to neutrinos. The effect on 0νββ decay is significant if the coupling violates the lepton number, for which the ΔL = 2 transition is directly driven by the dark matter field without further suppression of small neutrino masses. As the ultralight dark matter can be well described by a classical field, the effect features a periodic modulation pattern in decay events. However, we find that in the early Universe such coupling will be very likely to alter the standard cosmological results. In particular, the requirement of neutrino free-streaming before the matter-radiation equality severely constrains the parameter space, such that the future 0νββ decay experiments can hardly see any signal even with a meV sensitivity to the effective neutrino mass.

Refractive neutrino masses, ultralight dark matter and cosmology

“…The amplitude matches the field strength used in the cold gas computations. In addition, time variations of the field appear which have been studied extensively in a number of papers [9,[13][14][15][16][17][18][19][20][21][22][23][24].…”

“…In this connection, refraction effects of neutrinos on very light target particles due to exchange of light mediators were studied and the effective potentials were computed [5,8,12]. The phenomenology of neutrino-ultralight DM interactions has been explored extensively [9,[13][14][15][16][17][18][19][20][21][22][23][24].…”

Second leptogenesis: Unraveling the baryon-lepton asymmetry discrepancy

“…Thus, we obtain g 4 i > 8π 3 g * /90 T /M Pl . The coupling g i is also subject to constraints from various experimental studies, such as the Majoron emitting decay [71,72], neutrino free-streaming on the CMB [49], and neutrino oscillations [37] depending on the m ϕ values. However, their constraints are weaker than others in the parameter space we are interested in.…”

Light sterile neutrinos in the early universe: effects of altered dispersion relations and a coupling to axion-like dark matter

“…Another idea that has been proposed to reconcile light sterile neutrinos with cosmological data employs an axion-like particle (ALP) coupling to the sterile neutrinos via a Yukawa interaction term [26][27][28][29][30][31] (for non-cosmological applications of this particular class of models see also [32][33][34][35][36]). The additional, ultra-light scalar field ϕ is assumed to be an approximately homogeneous condensate behaving like a classical field.…”