Related papers: Low-mass X-ray binaries ejected from globular clus…
We present a sample of hard X-ray selected candidate black holes (BHs) in 19 dwarf galaxies. BH candidates are identified by cross-matching a parent sample of ~44,000 local dwarf galaxies (M_stellar < 3 x 10^9 Msun, z<0.055) with the…
This is the second paper in a series, which studies the likelihood that some globular clusters (GCs) of the Milky Way (MW) could have originated from a dwarf satellite galaxy (DSG). Using a large suite of three-body simulations we determine…
The discovery of stellar-mass black holes (BHs) in globular clusters (GCs) raises the possibility of long-term retention of BHs within GCs. These BHs influence various astrophysical processes, including merger-driven gravitational waves and…
Globular clusters (GCs) effectively produce dynamically-formed low-mass X-ray binaries (LMXBs). Observers detect ~100 times more LMXBs per stellar mass in GCs compared to stars in the fields of galaxies. It has also been observationally…
We combine the kinematics of 159 globular clusters (GCs) provided by the Gaia Early Data Release 3 (EDR3) with other observational data to classify the GCs, and to estimate the mass of the Milky Way (MW). We use the age-metallicity…
Black hole - neutron star $(BH/NS)$ binaries are of interest in many ways: they are intrinsically multi-messenger systems, highly transient, radiate gravitational waves detectable by LIGO, and may produce $\gamma$-ray bursts. Although it…
Many globular clusters (GCs) in the Milky Way (MW) have been studied in recent years, especially in hidden regions such as those of the Galactic bulge. Our main goal is to understand what we can learn if we include these new objects into…
We present a novel method combining existing cosmological simulations and orbital integration to study the hierarchical assembly of globular cluster (GC) populations in the Milky Way (MW). Our method models the growth and evolution of GC…
The existence of a mass gap of $3-5\,M_{\odot}$ between the heaviest neutron stars (NSs) and the lightest black holes (BHs), inferred from the BH mass distribution in low mass X-ray binaries (LMXBs), has been suggested for decades. The…
Recent Chandra observations of interacting and starburst galaxies have led us to investigate the apparent correlation between the positions of young star clusters and Chandra point sources. Assumed to be X-ray binaries (XRBs), these point…
We perform N-body simulations on some of the most massive galaxies extracted from a cosmological simulation of hierarchical structure formation with total masses in the range $10^{12} M_{\odot} < M_{tot} < 3\times 10^{13} M_{\odot}$ from…
X-ray binaries (XRBs) are probes of both star formation and stellar mass, but more importantly remain one of the only direct tracers of the compact object population. To investigate the XRB population in M31, we utilized all 121 publicly…
While tens or hundreds of stellar-remnant black holes are expected to form in globular star clusters, it is still unclear how many of those will be retained upon formation, and how many will be ejected through subsequent dynamical…
We investigate black hole-star binaries formed in $N$-body simulations of massive, dense star clusters. We simulate 32 clusters with varying initial masses ($10^{4}~\rm M_{\odot}$ to $10^{6}~\rm M_{\odot}$), densities ($1200~\rm…
The observed binary black hole (BBH) mergers indicate a large Galactic progenitor population continuously evolving from large orbital separations and low gravitational wave (GW) frequencies to the final merger phase. We investigate the…
We investigate whether the recently-observed population of high-velocity white dwarfs can be derived from a population of binaries residing initially within the thin disk of the Galaxy. In particular we consider binaries where the primary…
The dense environments in the cores of globular clusters (GCs) facilitate many strong dynamical encounters among stellar objects. These encounters have been shown capable of ejecting stars from the host GC, whereupon they become runaway…
Globular clusters (GCs), as old as our Galaxy, constantly lose their members to the field as they cross through the Milky Way (MW). These GC escaped stars (or escapees) are suggested to contribute significantly to the MW halo. If a star has…
We report on the archival optical and near-infrared observations of 6 low mass X-ray binaries situated in the Galactic bulge. We processed several recent Chandra and XMM-Newton as well as Einstein datasets of a binary systems suspected to…
We study the unresolved X-ray emission in three Local Group dwarf elliptical galaxies (NGC 147, NGC 185 and NGC 205) using XMM-Newton observations, which most likely originates from a collection of weak X-ray sources, mainly cataclysmic…