Related papers: Neutralino dark matter from heavy axino decay
We study the effect of the late decaying saxino (the scalar superpartner of the axion) and find out that there is a possible dark matter solution from a class of supersymmetric extensions of the invisible axion model. In this class of…
The decay of a false vacuum of unbroken B-L symmetry is an intriguing and testable mechanism to generate the initial conditions of the hot early universe. If B-L is broken at the grand unification scale, the false vacuum phase yields hybrid…
We present models of decaying particles for increasing the effective number of neutrinos N_nu after big bang nucleosynthesis but before the structure formation begins. We point out that our scenario not only solves the discrepancy between…
Dark matter may be coupled to dark radiation: light degrees of freedom that mediate forces between dark sector particles. Cosmological constraints favor dark radiation that is colder than Standard Model radiation. In models with fixed…
Dark matter may be composed of superWIMPs, superweakly-interacting massive particles produced in the late decays of other particles. We focus on the case of gravitinos produced in the late decays of sleptons or sneutrinos and assume they…
Supersymmetric models with t-b-\tau Yukawa unification at M_{GUT} qualitatively predict a sparticle mass spectrum including first and second generation scalars at the 3--15 TeV scale, third generation scalars at the (few) TeV scale and…
The thermal inflation is the most plausible mechanism that solves the cosmological moduli problem naturally. We discuss relic abundance of superheavy particle $X$ in the presence of the thermal inflation assuming that its lifetime is longer…
If the energy density of the Universe before nucleosynthesis is dominated by a scalar field $\phi$ that decays and reheats the plasma to a low reheating temperature $T_{RH}$, neutralinos may be warm dark matter particles. We study this…
The gravitino problem is revisited in the framework of cosmological models in which the primordial cosmic matter is described by a relativistic imperfect fluid. Dissipative effects (or bulk viscosity effects) arise owing to the different…
We point out that there is no cosmological gravitino problem in a certain class of gauge-mediated supersymmetry-breaking (GMSB) models. The constant term in the superpotential naturally causes small mixings between the standard-model and…
We revisit Higgs inflation in the framework of a minimal extension of the Standard Model gauge symmetry by a $U(1)_{B-L}$ factor. Various aspects are taken into account with particular focus on the role of the supersymmetry breaking (SUSY)…
One of the possible methods to distinguish among various dark matter candidates is to study the effects of dark matter decays. We consider four different dark matter candidates (light dark matter, gravitinos, neutralinos and sterile…
The recently constructed Dehnen-Binney set of mass models for the Galaxy is used to show that the decaying neutrino theory for the ionisation of the interstellar medium (Sciama 1990a, 1993) requires the neutrino halo of the Galaxy to be as…
The "gravitational baryogenesis" scenario is extended to generate both baryon and dark matter asymmetries, in the matter dominated era corresponding to post-inflationary reheating. A minimal extension requires a singlet fermion X for dark…
Assuming that there exists a species of heavy sterile neutrinos($m_{\nu}>1$ keV) and their decays can serve as a heating source of the hot gas in galaxy clusters, we study how the observational constraints on cooling flow limit the mass of…
In this talk, we present the package GravitinoPack that calculates decays of unstable supersymmetric particles, involving gravitinos in the final or initial state. If the gravitino is the dark matter particle and therefore stable, the…
Assuming the lightest neutralino forms dark matter, we study its residual annihilation after freeze-out at the early universe. If taking place after the big bang nucleosynthesis (BBN) the annihilation products, especially at the hadronic…
If local supersymmetry is the correct extension of the standard model of particle physics, then following Inflation the early universe would have been populated by gravitinos produced from scatterings in the hot plasma during reheating.…
We study the implications of a large baryogenesis temperature, $T_B = O(10^{10}$ GeV), on the mass spectrum of superparticles in supersymmetric extensions of the standard model. Models with a neutralino as lightest superparticle (LSP) are…
We present a detailed study of the production of dark matter in the form of a sterile neutrino via freeze-in from decays of heavy right-handed neutrinos. Our treatment accounts for thermal effects in the effective couplings, generated via…