Related papers: Effective field theory and keV lines from dark mat…
We derive new bounds on hadronically-interacting, sub-GeV mass dark matter. First, we show that one-loop interactions with photons can be sufficient to maintain equilibrium between the dark matter and Standard Model sectors at MeV…
We discuss the possibility that the recent detection of 511 keV gamma rays from the galactic bulge, as observed by INTEGRAL, can be naturally explained by the supermassive very dense droplets (strangelets) of dark matter. These droplets are…
Tentative evidence of a 3.5 keV X-ray line has been found in the stacked spectra of galaxy clusters, individual clusters, the Andromeda galaxy and the galactic center, leading to speculation that it could be due to decays of metastable dark…
We show that active neutrino masses and a keV-GeV mass sterile neutrino dark matter candidate can result from a modified, low energy seesaw mechanism if right-handed neutrinos are charged under a new symmetry broken by a scalar field vacuum…
We test the origin of the 3.5 keV line photons by analyzing the morphology of the emission at that energy from the Galactic Center and from the Perseus cluster of galaxies. We employ a variety of different templates to model the continuum…
New particles in theories beyond the standard model can manifest as stable relics that interact strongly with visible matter and make up a small fraction of the total dark matter abundance. Such particles represent an interesting physics…
We show that various scalar field models of dark energy predict degenerate luminosity distance history of the Universe and thus cannot be distinguished by supernovae measurements alone. In particular, models with a vanishing cosmological…
Based on tentative evidence for a peak in the Fermi gamma-ray spectrum originating from near the center of the galaxy, it has been suggested that dark matter of mass ~130 GeV is annihilating directly into photons with a cross section ~24…
We study the phenomenology of a $U_X(1)$ extension of the Standard Model where the SM particles are not charged under the new abelian group. The Green-Schwarz mechanism insures that the model is anomaly free. The erstwhile invisible dark…
If the unidentified emission line at ~3.55 keV previously found in spectra of nearby galaxies and galaxy clusters is due to radiatively decaying dark matter, one should detect the signal of comparable strength from many cosmic objects of…
Recently evidence for gamma ray lines at energies of approximately 111 and 128 GeV has been found in Fermi-LAT data from the center of the galaxy and from unassociated point sources. Many explanations in terms of dark matter particle pairs…
We consider the possibility that dark matter and dark energy can be explained by the minimal KSVZ axion model. This is possible if the lowest energy metastable minimum of the scalar potential has zero energy density, which is possible in…
We discuss the dynamics and phenomenology of an oscillating scalar field coupled to the Higgs boson that accounts for the dark matter in the Universe. The model assumes an underlying scale invariance such that the scalar field only acquires…
Lines in the spectrum of cosmic gamma rays are considered one of the more robust signatures of dark matter annihilation. We consider such processes from an effective field theory vantage, and find that generically, two or more lines are…
Naive intuition about scale decoupling breaks down in the presence of fermion masses. Kinematic enhancements can greatly extend the range where one needs to keep a finite mass in calculations to obtain a correct result at even the O(1)…
Dark matter (DM) particle annihilation or decay can produce monochromatic $\gamma$-rays readily distinguishable from astrophysical sources. $\gamma$-ray line limits from 30 GeV to 200 GeV obtained from 11 months of Fermi Large Area Space…
Popular extensions of the standard model of particle physics feature new fields and symmetries which could, for example, dynamically generate neutrino masses from $B-L$ spontaneous symmetry breaking. If a new light scalar that decays into…
Dark matter annihilation has been proposed to explain the TeV gamma rays observed from the Galactic Center. We study constraints on this hypothesis coming from the mass profile around the Galactic Center measured by observing stellar…
We consider axino warm dark matter in a supersymmetric axion model with R-parity violation. In this scenario, axino with the mass $m_\axino\simeq 7$ keV can decay into photon and neutrino resulting in the X-ray line signal at $3.5$ keV,…
We study the possibility of keV neutrino dark matter in the minimal $U(1)_{B-L}$ gauge extension of the standard model where three right handed neutrinos are automatically included due to the requirement of anomaly cancellations. Without…