Related papers: Quintessential Kination and Thermal Production of …
We examine axino dark matter in the regime of a low reheating temperature T_R after inflation and taking into account that reheating is a non-instantaneous process. This can have a significant effect on the dark matter abundance, mainly due…
We show that the isocurvature perturbations imply that the gravitationally produced superheavy dark matter must have masses larger than few times the Hubble expansion rate at the end of inflation. This together with the bound on tensor to…
Gravitino problem is discussed in detail. We derive an upperbound on the reheating temperature from the constraints of the big-bang nucleosynthesis and the present mass density of the universe. Compared to previous works, we have improve…
A weakly interacting massive particle (WIMP) is a leading candidate of the dark matter. The WIMP dark matter abundance is determined by the freeze-out mechanism. Once we know the property of the WIMP particle such as the mass and…
In this paper, we investigate a quintessence field with an exponential potential motivated by the suggestion of time-varying dark energy from the DESI galaxy survey. Assuming a kination epoch in the early Universe, we analytically derive…
Supersymmetry breaking sectors generically have an approximate global U(1) $R$-symmetry. Thermal effects tend to restore the $R$-symmetry in the reheated early universe. We revisit the gravitino generation from the thermal plasma and we…
We provide a detailed study of gravitational reheating in quintessential inflation generalizing previous analyses only available for the standard case when inflation is followed by an era dominated by the energy density of radiation.…
(Abridged) We study dissipative inflation in the regime where the dissipative term takes a specific form, \Gamma=\Gamma(\phi), analyzing two models in the weak and strong dissipative regimes with a SUSY breaking potential. After developing…
The cosmological moduli problem is discussed in the framework of sequestered sector/anomaly-mediated supersymmetry (SUSY) breaking. In this scheme, the gravitino mass (corresponding to the moduli masses) is naturally 10 - 100 TeV, and hence…
In models of universal extra dimensions, gravity and all standard model fields propagate in the extra dimensions. Previous studies of such models have concentrated on the Kaluza-Klein (KK) partners of standard model particles. Here we…
Weakly Interacting Massive Particles (WIMPs) have long reigned as one of the leading classes of dark matter candidates. The observed dark matter abundance can be naturally obtained by freezeout of weak-scale dark matter annihilations in the…
High-scale supersymmetry (SUSY) with a split spectrum has become increasingly interesting given the current experimental results. A SUSY scale above the weak scale could be naturally associated with a heavy unstable gravitino, whose decays…
Flat directions in generic supersymmetric theories can change the thermal history of the Universe. A novel scenario was proposed earlier where the vacuum expectation value of the flat directions induces large masses for all the gauge bosons…
We investigate the so-called superWIMP scenario with gravitino as the lightest supersymmetric particle (LSP) in the context of non-standard cosmology, in particular, brane world cosmology. As a candidate of the next-to-LSP (NLSP), we…
In the post-LHC8 era, it is perceived that what is left of SUSY model parameter space is highly finetuned in the EW sector (EWFT). We discuss how conventional measures overestimate EWFT in SUSY theory. Radiatively-driven natural SUSY (RNS)…
Recently, both the ATLAS and CMS experiments have observed an excess of events that could be the first evidence for a 125 GeV Higgs boson. We investigate an implication of the CP-even Higgs boson with mass around 125 GeV in the context of…
Quintessential inflation provides a unified description of the early and late accelerated phases of the Universe, linking the inflationary epoch to the present-day dark energy-dominated era through a single scalar degree of freedom. In this…
We report results from searches of pseudoscalar and vector bosonic super-weakly interacting massive particles (super-WIMP) in the TEXONO experiment at the Kuo-Sheng Nuclear Power Station, using 314.15 kg days of data from $n$-type…
If one simultaneously invokes the SUSY solution to the gauge hierarchy problem and the PQ solution to the strong CP problem, then one might expect mixed axion/neutralino dark matter (DM), i.e. two dark matter particles. In this case, dark…
We consider the potential problems due to the production of inflatinos and gravitinos after inflation. Inflationary models with a single scale set by the microwave background anisotropies have a low enough reheat temperature to avoid…