Related papers: Constraining D-foam via the 21-cm Line
The conventional cold, particle interpretation of dark matter (CDM) still lacks laboratory support and struggles with the basic properties of common dwarf galaxies, which have surprisingly uniform central masses and shallow density…
We show that there exists only a quite limited number of higher dimensional operators which can naturally lead to a slow decay of dark matter particles into monochromatic photons. As each of these operators inevitably induces decays into…
We investigate constraints on the interactions of light dark matter with Standard Model quarks in a framework with effective contact operators mediating the decay of heavy flavor bound state quarkonium to dark matter and a photon. When…
The physics of light-matter interactions is strongly constrained by both the small value of the fine-structure constant and the small size of the atom. Overcoming these limitations is a long-standing challenge. Recent theoretical and…
Ultralight particles, with a mass below the electronvolt scale, exhibit wave-like behavior and have arisen as a compelling dark matter candidate. A particularly intriguing subclass is scalar dark matter, which induces variations in…
The mass and composition of dark matter (DM) particles and the shape and damping scales of the power spectrum of density perturbations can be estimated from recent observations of the DM dominated relaxed objects -- dwarf galaxies and…
Despite the great success of the Standard Model of particle physics the nature of Dark Matter still remains unclear. Recently, the idea of the existence of a hidden sector coupling only weakly with the ordinary matter was revitalized and…
Dark matter could be made up of dark photons, massive but very light particles whose interactions with matter resemble those of usual photons but suppressed by a small mixing parameter. We analyze the main approaches to dark photon…
We study a two-component dark matter model consisting of a Dirac fermion and a complex scalar charged under new U(1) gauge group in the hidden sector. The dark fermion plays the dominant component of dark matter which explains the measured…
Neutrinos -- amongst the lightest known particles -- can mediate a force driving dark matter self-interaction and the small scale structure of the universe. We explore such a possibility in the simplest neutrino portal dark sector model…
We explore theories of dark matter in which dark matter annihilations produce mono-energetic gamma rays ("lines") in the context of effective field theory, which captures the physics for cases in which the particles mediating the…
While the evidence for dark matter continues to grow, the nature of the dark matter remains a mystery. A dark $U(1)_D$ gauge theory can have a small kinetic mixing with the visible photon which provides a portal to the dark sector. Magnetic…
The possible existence of a new gauge boson U, light and very weakly coupled, allows for Light Dark Matter particles, which could also be at the origin of the 511 keV line from the galactic bulge. Independently of dark matter, and taking…
We propose a simple yet testable framework for light fermion dark matter (DM) with mass in the MeV--GeV range, charged under a dark $U(1)_D$ gauge symmetry. The $U(1)_D$ is spontaneously broken by a scalar field $\Phi$, giving mass to the…
Here we briefly review possible indirect effects of dark matter (DM) of the Universe. It includes effects in cosmic rays (CR): first of all, the positron excess at $\sim$ 500 GeV and possible electron-positron excess at 1-1.5 TeV. We tell…
Using standard techniques in string/D-brane scattering amplitude computations, we evaluate the scattering of open strings off D-particles in brane world scenarios. The D-particles are viewed as D3 branes wrapped up around three cycles, and…
In the vast expanse of our galaxy, white dwarfs (WDs) are natural sentinels, capturing the enigmatic dark matter (DM) particles that incessantly traverse their interiors. These celestial bodies provide a unique vantage point for probing…
We explore a new mechanism for reproducing the Dark Matter (DM) abundance: scatterings of one DM particle on light Standard Model particles. Strong bounds on its decays can be satisfied if DM undergoes freeze-in and has a mass around or…
I discuss a specific model of space-time foam, inspired by the modern non-perturbative approach to string theory (D-branes). The model views our world as a three brane, intersecting with D-particles that represent stringy quantum gravity…
In this article, we have done a thorough investigation of the possible effects of interaction between dark matter (DM) and neutrinos on reionization history. We have constrained the interaction strength using 21 cm Cosmology and found out…