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Related papers: The degenerate gravitino scenario

200 papers

The R-Parity symmetry Violating (RPV) version of the Next-to-Minimal Supersymmetric Standard Model (NMSSM) is attractive simultaneously with regard to the so-called mu-problem and the accommodation of three-flavor neutrino data at tree…

High Energy Physics - Phenomenology · Physics 2015-03-13 C. -C. Jean-Louis , G. Moreau

We review our recent results on dark matter from Starobinsky supergravity. In this context, a natural candidate for Cold Dark Matter is the gravitino. On the other hand, assuming the supersymmetry broken at scales much higher than the…

General Relativity and Quantum Cosmology · Physics 2017-05-24 Andrea Addazi , Maxim Yu. Khlopov

We re-consider the gravitino as dark matter in the framework of the Constrained MSSM. We include several recently suggested improvements on: (i) the thermal production of gravitinos, (ii) the calculation of the hadronic spectrum from NLSP…

High Energy Physics - Phenomenology · Physics 2010-04-23 Sean Bailly , Ki-Young Choi , Karsten Jedamzik , Leszek Roszkowski

Gravitinos are a fundamental prediction of supergravity, their mass ($m_{G}$) is informative of the value of the SUSY breaking scale, and, if produced during reheating, their number density is a function of the reheating temperature…

High Energy Physics - Phenomenology · Physics 2018-07-11 Emanuela Dimastrogiovanni , Lawrence M. Krauss

In split-supersymmetry (split-SUSY), gluino is a metastable particle and thus can freeze out in the early universe. The late decay of such a long-life gluino into the lightest supersymmetric particle (LSP) may provide much of the cosmic…

High Energy Physics - Phenomenology · Physics 2009-11-11 Fei Wang , Wenyu Wang , Jin Min Yang

The axino and the gravitino are well-motivated candidates for the lightest supersymmetric particle (LSP) and also for cold dark matter in the Universe. Assuming that a charged slepton is the next-to-lightest supersymmetric particle (NLSP),…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Brandenburg , L. Covi , K. Hamaguchi , L. Roszkowski , F. D. Steffen

We investigate thermal leptogenesis in a supersymmetric neutrinophilic Higgs model by taking phenomenological constraints into account, where, in addition to the minimal supersymmetric standard model, we introduce an extra Higgs field with…

High Energy Physics - Phenomenology · Physics 2015-05-28 Naoyuki Haba , Osamu Seto

In a large class of supersymmetric (SUSY) axion model the mass of axino $\axino$ (a fermionic superpartner of the axion) is predicted as $m_{\axino} \lesssim {\cal O}(1)$ keV. Thus, the axino is the lightest SUSY particle (LSP). We pointed…

High Energy Physics - Phenomenology · Physics 2011-07-18 T. Asaka , T. Yanagida

We consider theories with spontaneously broken global or local supersymmetry where the pseudo-goldstino or the gravitino is the lightest superparticle (LSP). Assuming that the long-lived next-to-lightest superparticle (NSP) is a charged…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wilfried Buchmuller , Koichi Hamaguchi , Michael Ratz , Tsutomu Yanagida

The thermal leptogenesis in brane world cosmology is studied. In brane world cosmology, the expansion law is modified from the four-dimensional standard cosmological one at high temperature regime in the early universe. As a result, the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Nobuchika Okada , Osamu Seto

Models of leptogenesis are constrained by the low reheat temperature at the end of reheating associated with the gravitino bound. However a detailed view of reheating, in which the maximum temperature during reheating, $\Tmax$, can be…

High Energy Physics - Phenomenology · Physics 2008-11-26 Raghavan Rangarajan , Narendra Sahu

In supersymmetric theories, the gravitino is abundantly produced in the early Universe from thermal scattering, resulting in a strong upper bound on the reheat temperature after inflation. We point out that the gravitino problem may be…

High Energy Physics - Phenomenology · Physics 2017-11-22 Raymond T. Co , Keisuke Harigaya

In MSSM scenarios where the gravitino is the lightest supersymmetric particle (LSP), and therefore a viable dark matter candidate, the stop $\tilde{t}_1$ could be the next-to-lightest superpartner (NLSP). For a mass spectrum satisfying:…

High Energy Physics - Phenomenology · Physics 2016-08-16 J. Lorenzo Díaz Cruz , Bryan O. Larios

Gravitino Dark Matter represents a compelling scenario in Supersymmetry, which brings together a variety of data from cosmology and collider physics. We discuss the constraints obtained from the LHC on supersymmetric models with gravitino…

High Energy Physics - Phenomenology · Physics 2015-12-23 Alexandre Arbey , Marco Battaglia , Laura Covi , Jasper Hasenkamp , Farvah Mahmoudi

If the gravitino is sufficiently light and stable it will behave as an effective massless neutrino species at the time of nucleosynthesis. Depending on the temperature at which it decouples from the thermal bath in the early universe, the…

High Energy Physics - Phenomenology · Physics 2009-10-28 Tony Gherghetta

We investigate the possibility that the entropy producing decay of a right-handed sneutrino condensate can simultaneously be the source of the baryon asymmetry, of gravitino dark matter, and of cosmological density perturbations. For…

High Energy Physics - Phenomenology · Physics 2009-11-10 Rouzbeh Allahverdi , Manuel Drees

Scenarios with gravitino dark matter face potential cosmological problems induced by the presence of the Next-to-Lightest Supersymmetric Particle (NLSP) at the time of Big Bang Nucleosynthesis (BBN). A very simple, albeit radical, solution…

High Energy Physics - Phenomenology · Physics 2007-10-16 Alejandro Ibarra

We investigate the possibility of probing high reheating temperature scenarios at the LHC, in supersymmetric models where the gravitino is the lightest supersymmetric particle, and the stau is the next-to-lightest supersymmetric particle.…

High Energy Physics - Phenomenology · Physics 2010-11-09 Motoi Endo , Koichi Hamaguchi , Kouhei Nakaji

Thermal leptogenesis in the canonical seesaw model in supersymmetry suffers from the incompatibility of a generic lower bound on the mass scale of the lightest right-handed neutrino and the upper bound on the reheating temperature of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ernest Ma , Narendra Sahu , Utpal Sarkar

Cosmological issues are examined when gravitino is the lightest superparticle (LSP) and R-parity is broken. Decays of the next lightest superparticles occur rapidly via R-parity violating interaction, and thus they do not upset the big-bang…

High Energy Physics - Phenomenology · Physics 2011-05-05 Fumihiro Takayama , Masahiro Yamaguchi