Related papers: A new direction for dark matter research: intermed…
The measurements of the possible gravitational microlensing events are analysed with a simple yet accurate disc--halo model of the Milky Way Galaxy. This comprises a luminous exponential disc embedded in a flattened dark matter halo with…
We review some recent determinations of the amount of dark matter on galactic and larger scales, with special attention to the dark matter in the Milky Way. We then briefly review the motivation for and basic physics of several dark matter…
The primary goal of this paper is to provide the evidence that can either prove or falsify the hypothesis that dark matter in the Galactic halo can clump into stellar-mass compact objects. If such objects existed, they would act as lenses…
We use numerical simulations to examine the substructure within galactic and cluster mass halos that form within a hierarchical universe. Clusters are easily reproduced with a steep mass spectrum of thousands of substructure clumps that…
It is now well-established that a dark, compact object (DCO), very likely a massive black hole (MBH) of around four million solar masses is lurking at the centre of the Milky Way. While a consensus is emerging about the origin and growth of…
We suggest a new component of the Milky Way galaxy that can account for both the optical depth and the event durations obtained by the MACHO microlensing survey toward the Large Magellanic Cloud. This component is consistent with recent…
Since the first discovery of microlensing events nearly two decades ago, gravitational microlensing has accumulated tens of TBytes of data and developed into a powerful astrophysical technique with diverse applications. The review starts…
We suggest a new component of the Milky Way that can account for both the optical depth and event durations implied by microlensing searches targeting the Large Magellanic Cloud. This component, which represents less than 4% of the total…
Stellar microlensing surveys are a powerful tool for probing dark matter in the form of planetary and stellar mass compact objects (COs), in particular primordial black holes (PBHs). Under standard assumptions, current observations exclude…
The Milky Way's dark matter halo is expected to host numerous low-mass subhalos with no detectable associated stellar component. Such subhalos are invisible unless their dark matter annihilates to visible states such as photons. One of the…
A new kind of dark matter structures, ultracompact minihalos (UCMHs) was proposed recently. They would be formed during the radiation dominated epoch if the large density perturbations are existent. Moreover, if the dark matter is made up…
Dark matter in the form of compact objects with mass $M_{\rm co} \gtrsim 10 M_{\odot}$ can be constrained by its dynamical effects on wide binary stars. Motivated by the recent interest in Primordial Black Hole dark matter, we revisit the…
The MACHO collaboration lensing event statistics suggest that a significant fraction of the dark galactic halo can be comprised of baryonic matter in the form of white dwarf stars with masses between 0.1 and 1.0 \Msun . Such a halo white…
We demonstrate a novel mechanism for producing dark compact objects and black holes through a dark sector, where all the dark matter can be dissipative. Heavy dark sector particles with masses above $10^4$ GeV can come to dominate the…
It is assumed that a galaxy starts as a dark halo of a few million Jeans clusters (JCs), each of which consists of nearly a trillion micro brown dwarfs, MACHOs of Earth mass. JCs in the galaxy center heat up their MACHOs by tidal forces,…
The dark matter in the halos of galaxies may well be baryonic, and much of the mass within them could be in the form of clusters of substellar objects within which are embedded cold gas globules. Such halos might play an active role in…
In the standard model of cosmic structure formation, dark matter haloes form by gravitational instability. The process is hierarchical: smaller systems collapse earlier, and later merge to form larger haloes. The galaxy clusters, hosted by…
A small admixture of dark matter gravitationally bound to the proto-Solar gas cloud could be adiabatically contracted into Earth-crossing orbits with a local density comparable to (or even exceeding) the Galactic halo density. We show that…
The present surge for the astrophysical relevance of boson stars stems from the speculative possibility that these compact objects could provide a considerable fraction of the non-baryonic part of dark matter within the halo of galaxies.…
We explore the prospect of producing primordial black holes around the solar mass region during an early matter domination epoch. The early matter-dominated epoch can arise when a moduli field comes to dominate the energy density of the…