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Bhattacharya, Subhaditya

Publications and source records attributed to Bhattacharya, Subhaditya.

6 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Multipartite interacting scalar dark matter in the light of updated LUX data

We explore constraints on multipartite dark matter (DM) framework composed of singlet scalar DM interacting with the Standard Model (SM) through Higgs portal coupling. We compute relic density and direct search constraints including the updated LUX bound for two component scenario with non-zero interactions between two DM components in Z{sub 2} × Z{sub 2}{sup '} framework in comparison with the one having O(2) symmetry. We point out availability of a significantly large region of parameter space of such a multipartite model with DM-DM interactions.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2017

Neutrino masses and scalar singlet dark matter

Here We propose a simple extension of the Standard Model (SM) which has a viable dark matter (DM) candidate and can explain the generation of tiny neutrino masses. The DM is an electroweak (EW) singlet scalar S, odd under an imposed exact Z 2 symmetry, that interacts with the SM through the “Higgs portal” coupling, while all other particles are even under Z 2 . The model also has an EW isospin 3/2 scalar Δ and a pair of EW isospin vectors Σ and $\bar{Σ}$, which are responsible for generating tiny neutrino mass via the effective dimension-seven operator. Thanks to the additional interactions with Δ, the scalar singlet DM S survives a large region of parameter space by relic density constraints from WMAP/Planck and direct search bounds from updated LUX data. Constraints on the model from the LHC are also discussed.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2016

750 GeV diphoton excess at CERN LHC from a dark sector assisted scalar decay

We present a simple extension of the Standard Model (SM) to explain the recent diphoton excess, reported by CMS and ATLAS at CERN LHC. The SM is extended by a dark sector including a vector-like lepton doublet and a singlet of zero electromagnetic charge, which are odd under a Z{sub 2} symmetry. The charged particle of the vector-like lepton doublet assist the additional scalar, different from SM Higgs, to decay to di-photons of invariant mass around 750 GeV and thus explaining the excess observed at LHC. The admixture of neutral component of the vector-like lepton doublet and singlet constitute the dark matter of the Universe. We show the relevant parameter space for correct relic density and direct detection of dark matter.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗