Decaying dark matter with heavy axino

Abstract

A TeV scale decaying dark matter chiral multiplet N is introduced in addition to the minimal supersymmetric standard model(MSSM). For a calculable abundance of N, we introduce heavy axino decaying to N and MSSM particles including the lightest supersymmetric particle(LSP). In the scenario that heavy axino, once dominating the energy density of the universe, decays after the LSP decouples, it is possible to estimate the relative cosmic abundances of N and the LSP. Dimension 6 interactions allow the lifetime of the fermionic or the bosonic superpartner of N in the 10^{27} s range to be compatible with the recent astrophysical bounds. A diagrammatic strategy obtaining a suppression factor 1/M^2 is also given.Comment: 5 pages with 2 figure

Dark matter production in the early Universe: Beyond the thermal WIMP paradigm

“…The case where the axino mass is greater than the gravitino mass [462] is particularly interesting as a possible explanation of recent data from PAMELA [128] and from AMS-02 [77] which could imply a TeV scale WIMP mass if the WIMP is CDM. In Ref.…”

“…Alternatively, axinos may serve as a CDMgenerating mother particles, a possibility first considered in Ref. [218] and used in GUTs [462]. In both cases, the non-thermal production of axinos or WIMPs is a key mechanism for CDM production.…”

“…In Ref. [462], the superheavy axino was shown to account for TeV-scale cosmic-ray positrons produced as decay products of, for example, an NMSSM singlinoÑ toẽ plus e + , but not to antiprotons. This is possible in a string-derived flipped SU(5) grand unification model [187].…”

Axino cold dark matter revisited

“…As a digression, we note that, when axinos are very heavy, and it is the neutralinos that play the role of the LSP, their population from heavy axino decays could constitute CDM [38], leading in particular to the possibility of TeV-scale cosmic ray positrons, as pointed out in ref. [39]. The possibility of either WDM or very heavy axinos is not discussed in this paper.…”

Dark energy, QCD axion, BICEP2, and trans-Planckian decay constant

“…A typical example for the discrete symmetry is Z 10 R as shown in [13]. The Z 10 R charges descend from a gauge U(1) charges of the string compactification [19]. Then, the height of the potential is highly suppressed and we can obtain 10 −47 GeV 4 , without the gravity spoil of the global symmetry.…”