Cosmological implications of supersymmetric axion models

Abstract

Abstract. We derive general constraints on supersymmetric extension of axion models, in particular paying careful attention to the cosmological effects of saxion. It is found that for every mass range of the saxion from keV to TeV, severe constraints on the energy density of the saxion are imposed. Together with constraints from axino we obtain stringent upper bounds on the reheating temperature. ‡ Now,

Discrete gauge symmetry and Aharonov-Bohm radiation in string theory

“…In addition to these constraints, we have also investigated constraints coming from the Cosmic Microwave Background (CMB), reionization and the effective number of neutrinos along the lines of [61][62][63] 5 (see [64] for a review). But since these constraints are relatively weak and covered by the BBN and the diffuse γ-ray background, we do not exhibit them here.…”

Revisiting the cosmological coherent oscillation

“…As shown in the previous work [23], the abundance of the saxion is strongly constrained from cosmological observations. If we succeed in reducing the abundance of the saxion, the cosmologically viable model parameter space can be extended, and it is very important when one tries to build a SUSY axion model.…”

“…In particular, it is remarkable that the cosmological constraints for the saxion is much weakened than previously thought [23] at the region m σ > T R . Note that since the PQ symmetry is broken after inflation, cosmic strings are formed at the PQ phase transition.…”

“…In the SUSY axion model, the scalar partner of the axion, saxion, and the fermionic superpartner of the axion, axino, are included in the PQ supermultiplet and they take significant roles in cosmology [17,18,19,20,21,22,23,24]. In this section, we focus on the dynamics of the saxion and verify that the mechanism shown in the previous section is applicable.…”

Cosmological constraints on axionic dark radiation from axion-photon conversion in the early Universe

“…The cosmological constraints on the presence of such high-energy photon injection were summarized in Ref. [56], which, in the …”