Related papers: Dark Matter Spikes and Indirect Detection
Models of superdense star clusters at the center of galaxies are investigated to see whether such objects can be stable and long-lived based on evaporation and collision time-scales and stability criteria. We find that physically reasonable…
We reinvestigate the effect of annihilations on the distribution of collisionless dark matter (DM) in a spherical density spike around a massive black hole. We first construct a very simple, pedagogic, analytic model for an isotropic phase…
If a component of dark matter has dissipative interactions, it can cool to form compact astrophysical objects with higher density than that of conventional cold dark matter (sub)haloes. Dark matter annihilations might then appear as point…
In most supersymmetic models, neutralino dark matter particles are predicted to accumulate in the Galactic center and annihilate generating, among other products, gamma rays. The EGRET experiment has made observations in this region, and is…
This work analyzes the detection prospects for weakly interacting massive particles (WIMPs) in dark matter (DM) density spikes around nearby supermassive black holes (SMBHs) by observations in very high energy gamma-ray band. Such spikes…
The annihilation of weakly interacting massive particles can provide an important heat source for the first (Pop. III) stars, potentially leading to a new phase of stellar evolution known as a "Dark Star". When dark matter (DM) capture via…
We consider the possibility that the dark matter is coupled through its mass to a scalar field associated with the dark energy of the Universe. In order for such a field to play a role at the present cosmological distances, it must be…
For any realistic halo profile, the Galactic Center is predicted to be the brightest source of gamma-rays from dark matter annihilations. Due in large part to uncertainties associated with the dark matter distribution and astrophysical…
Formation and disruption of dark-matter cusps are reviewed. Accumulation of baryons at the center of a halo can displace the dark matter, converting singular density cusps into low-density cores. The displaced mass can be of order 10 M_b…
Searches for dark matter imprints are one of the most active areas of current research. We focus here on light fields with mass $m_B$, such as axions and axion-like candidates. Using perturbative techniques and full-blown nonlinear…
We show that the position of the central dark matter density peak may be expected to differ from the dynamical center of the Galaxy by several hundred parsec. In Eris, a high resolution cosmological hydrodynamics simulation of a realistic…
The Fermi Large Area Telescope observed an excess in gamma ray emission spectrum coming from the center of the Milky Way galaxy. This data reveals that a light Dark Matter (DM) candidate of mass in the range 31-40 GeV, dominantly decaying…
Using high-accuracy rotation curves of spiral galaxies, we derive distributions of the surface mass density. Comparing with the luminosity profiles, we show that the dark mass in disk and bulge distributions follows those of luminous…
In unified field theory the cosmological model of the universe has supersymmetric fields. Supersymmetric particles as dark and normal matter in galaxy clusters have a phase separation. Dark matter in halos have a statistical physics…
The centers of galaxies host a supermassive black hole surrounded by a dense stellar cluster. The cluster is expected to develop mass segregation, in which gravitational scatterings among the stars cause heavier objects to sink closer to…
The central regions of galaxies show the presence of massive black holes and/or dense stellar systems. The question about their modes of formation is still under debate. A likely explanation of the formation of the central dense stellar…
Excess Fermi GeV emission around the Galactic Centre has been interpreted as a possible signature of annihilating dark matter. Here we analyse three aspects of this claim: its spectral cutoff, the correlation between the spectral shape of…
In this dissertation, we look at environmental effects in extreme and intermediate mass ratio inspirals into massive black holes. In these systems, stellar mass compact objects orbit massive black holes and lose orbital energy due to…
Multi-messenger observations of astrophysical transients provide powerful probes of the underlying physics of the source as well as beyond the Standard Model effects. We explore transients that can occur in the vicinity of supermassive…
Although dark matter makes up 80% of the gravitational mass of our Galaxy, its composition is not known. One hypothesis is that dark matter consists of massive particles called WIMPs. WIMPs are expected to accumulate and coannihilate in the…