相关论文: Soft Leptogenesis and Gravitino Dark Matter in Gau…
Successful soft leptogenesis requires small B-terms for the right-handed sneutrinos and a large CP violating phase between the A- and B-terms. We show that this situation is realized naturally within the framework of gauge mediated…
Gauge mediation provides us with a complete picture of supersymmetry breaking and its mediation within the effective field theories, and thus allows us to discuss consistencies with low-energy particle physics as well as cosmological…
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…
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…
It is shown that gravitinos with mass m_{3/2} ~ 0.1-1 MeV may provide suitable cold dark matter candidates in scenarios of gauge mediated supersymmetry breaking (GMSB) under SO(10) grand unification coupled to supergravity, which…
We investigate the possibility that dark matter and the baryon asymmetry of the Universe are generated by the same mechanism, following an idea initially proposed by V.A. Kuzmin and recently discussed by R. Kitano and I. Low. In our model,…
Motivated by the fact that, in some realistic models combining SO(10) GUTs and flavour symmetries, it is not possible to achieve the required baryon asymmetry through the CP asymmetry generated in the decay of right-handed neutrinos, we…
We analyze leptogenesis in gauge extensions of the Standard Model with keV sterile neutrino dark matter. We find that both the observed dark matter abundance and the correct baryon asymmetry of the Universe can simultaneously emerge in…
We study the phenomenon of baryogenesis via leptogenesis in the gauged $B-L$ symmetric models by embedding the currently proposed model $\nu MSM$. It is shown that the lightest right handed neutrino of mass $100 GeV$ satisfy the…
A simple model is constructed based on the gauge symmetry $SU(3)_c \times SU(2)_L \times U(1)_Y \times SU(2)_\ell$, with only the leptons transforming nontrivially under $SU(2)_\ell$. The extended symmetry is broken down to the Standard…
We investigated the viability of neutralino dark matter in the gauge mediation from emergent supersymmetry proposal. In this proposal, supersymmetry is broken at Planck scale and consequently, the gravitino is superheavy and completely…
We present a new scenario of gravitino dark matter which is compatible with the thermal leptogenesis. We confirm by an explicit calculation in supergravity that the relic abundance of thermally produced gravitino becomes insensitive to the…
We implement soft leptogenesis in a warped five dimensional scenario with two branes on the orbifold boundaries coming from an S^{1}/Z_{2} symmetry, and supersymmetry broken on the IR brane. The SM hypermultiplet fields (fermions and Higgs)…
We explore the possibility of gauge mediation in a paradigm whereby supersymmetry is posited to be an accidental symmetry of Nature and the Standard Model fields are composite bound states that emerge from a conformal field theory. The…
We revisit the idea of generating the Higgs mu parameter through a spontaneously broken Peccei-Quinn (PQ) symmetry in gauge-mediated supersymmetry breaking scenario. For the messenger scale of gauge mediation higher than the PQ scale, the…
We discuss a scenario in which the supergravity induced soft terms, conventionally used for breaking supersymmetry, also lead to non-zero Majorana neutrino masses. The soft terms lead to the spontaneous violation of the lepton number at the…
In conventional models of gauge-mediated supersymmetry breaking, the lightest supersymmetric particle (LSP) is invariably the gravitino. However, if the supersymmetry breaking sector is strongly coupled, conformal sequestering may raise the…
We study ``soft leptogenesis'', a new mechanism of leptogenesis which does not require flavour mixing among the right-handed neutrinos. Supersymmetry soft-breaking terms give a small mass splitting between the CP-even and CP-odd…
We show that gravitinos produced by decays of a supersymmetry breaking scalar field (the pseudo-moduli field) can naturally explain the observed abundance of dark matter in a certain class of the gauge mediation models. We study the decay…
In a recent work, a model of gauge mediation with sequestered supersymmetry (SUSY) breaking was proposed. In this model, the mass of the gravitino is O(100) GeV without causing the flavor-changing neutral-current problem. In contrast to…