Subhendra Mohanty

Theory of neutrinos: a white paper

This paper is a review of the present status of neutrino mass physics, which grew out of an APS sponsored study of neutrinos in 2004. After a discussion of the present knowledge of neutrino masses and mixing and some popular ways to probe the new physics implied by recent data, it summarizes what can be learned about neutrino interactions as well as the nature of new physics beyond the Standard Model from the various proposed neutrino experiments. The intriguing possibility that neutrino mass physics may be at the heart of our understanding of a long standing puzzle of cosmology, i.e. the origin of matter?antimatter asymmetry is also discussed.

Dipolar dark matter

If dark matter (DM) has nonzero direct or transition, electric or magnetic dipole moment then it can scatter nucleons electromagnetically in direct detection experiments. Using the results from experiments like XENON, CDMS, DAMA, and COGENT, we put bounds on the electric and magnetic dipole moments of DM. If DM consists of Dirac fermions with direct dipole moments, then DM of mass less than 10 GeV is consistent with the DAMA signal and with null results of other experiments. If on the other hand DM consists of Majorana fermions then they can have only nonzero transition moments between different mass eigenstates. We find that Majorana fermions with masses 38 < or approx. m{sub {chi}} < or approx. 100-200 GeV and mass splitting of the order of (150-200) keV can explain the DAMA signal and the null observations from other experiments and in addition give the observed relic density of DM by dipole-mediated annihilation. The absence of the heavier DM state in the present Universe can be explained by dipole-mediated radiative decay. This parameter space for the mass and for dipole moments is allowed by limits from L3 but may have observable signals at LHC.

Enhanced polarization of the cosmic microwave background radiation from thermal gravitational waves.

If inflation was preceded by a radiation era then at the time of inflation there will exist a decoupled thermal distribution of gravitons. Gravitational waves generated during inflation will be amplified by the process of stimulated emission into the existing thermal distribution of gravitons. Consequently the usual zero temperature scale invariant tensor spectrum is modified by a temperature dependent factor. This thermal correction factor amplify the

Reconciling the muon g − 2 and dark matter relic density with the LHC results in nonuniversal gaugino mass models

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Non-universal gaugino mass GUT models in the light of dark matter and LHC constraints

-mode polarization of the CMB by an order of magnitude at large angles, which may now be in the range of observability of WMAP.

Triplet-singlet extension of the MSSM with a 125 GeV Higgs boson and dark matter

A bstractRelatively light electroweak superparticle masses are required to satisfy the bulk annihilation region of dark matter relic density and account for the observed excess of muon g − 2, while TeV scale squark and gluino masses are required to account for the 125 GeV Higgs boson mass and the negative SUSY search results from 7 TeV LHC in most SUSY models. These two sets of requirements can be reconciled in a simple nonuniversal gaugino mass model, which assumes SUSY breaking via a combination of two superfields belonging to the singlet and the 200-plet representations of the GUT group SU(5). The model can be probed via squark/gluon search with the present and future LHC data. In a more general nonuniversal gaugino mass model the squark and gluino masses can be raised to the edge of the discovery limit of 14 TeV LHC or beyond. This model can be probed, however, through the search for electroweak pair production of the relatively light sleptons and winos with the 14 TeV LHC data in future.

Temperature of the inflaton and duration of inflation from wilkinson microwave anisotropy probe data

A bstractWe perform a comprehensive study of SU(5), SO(10) and E(6) supersymmetric GUT models where the gaugino masses are generated through the F-term breaking vacuum expectation values of the non-singlet scalar fields. In these models the gauginos are non-universal at the GUT scale unlike in the mSUGRA scenario. We discuss the properties of the LSP which is stable and a viable candidate for cold dark matter. We look for the GUT scale parameter space that leads to the the lightest SM like Higgs mass in the range of 122-127 GeV compatible with the observations at ATLAS and CMS, the relic density in the allowed range of WMAP-PLANCK and compatible with other constraints from colliders and direct detection experiments. We scan universal scalar

Constraints on decay plus oscillation solutions of the solar neutrino problem

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No scale SUGRA SO(10) derived Starobinsky Model of Inflation

, trilinear coupling A0 and SU(3)C gaugino mass

Neutrino coupling to cosmological background: A review on gravitational Baryo/Leptogenesis

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