Related papers: CV and LMXB Population Synthesis
We present a study on low-mass contact binaries (LMCB) with orbital periods shorter than 0.3 days and total mass lower than about 1.4 solar mass. We show that such systems have a long pre-contact phase, which lasts for 8-9 Gyrs, while the…
A binary in which a slightly evolved star starts mass transfer to a neutron star can evolve towards ultra-short orbital periods under the influence of magnetic braking. This is called magnetic capture. We investigate in detail for which…
We investigate the relationship between Low Mass X-ray Binaries (LMXBs) and globular clusters (GCs) using UKIRT observations of M31 and existing Chandra, XMM-Newton, and ROSAT catalogues. By fitting King models to these data we have…
We have observed several magnetic cataclysmic variables located in the range between 2 and 3 hours, known as the period gap. This work was prompted by the recent discovery of RX J1554.2+2721. It has 2.54 hours orbital period and shows…
Currently, there are 24 black hole (BH) X-ray binary systems that have been dynamically confirmed in the Galaxy. Most of them are low-mass X-ray binaries (LMXBs) comprised of a stellar-mass BH and a low-mass donor star. Although the…
The evolution of Cataclysmic Variables (CVs) is driven by period-changes ($\dot{P}$), for which the long-venerable consensus is the Magnetic Braking Model (MBM). The MBM has its only distinctive assumption being a power-law `recipe'…
We systematically investigate the effects of high supernova kick velocities on the orbital parameters of post-supernova neutron-star binaries. Using Monte- Carlo simulations, we determine the post-supernova distributions of orbital…
Context. Ultracompact X-ray binaries (UCXBs) typically consist of a white dwarf donor and a neutron star or black hole accretor. The evolution of UCXBs and very low mass ratio binaries in general is poorly understood. Aims. We investigate…
We summarize the status of art of the secular evolution of low mass X-ray binaries (LMXBs) and take a close look at the orbital period distribution of LMXBs and of binary millisecond pulsars (MSP), in the hypothesis that this latter results…
Using available astrometric and radial velocity data, the space velocities of cataclysmic variables (CVs) with respect to Sun were computed and kinematical properties of various sub-groups of CVs were investigated. Although observational…
We show that stable disk accretion should be very rare among low-mass X-ray binaries and cataclysmic variables whose evolution is driven by the nuclear expansion of the secondary star on the first giant branch. Stable accretion is confined…
Six gravitational wave events have been reported by the LIGO-Virgo collaboration (LVC), five of them associated with black hole binary (BHB) mergers and one with a double neutron star (DNS) merger, while the coalescence of a black…
Natal supernova kicks, the linear momentum compact remnants receive during their formation, are an essential part of binary population synthesis (BPS) models. Although these kicks are well-supported by evidence, their underlying…
We estimate the relativistic binaries merger rate and redshift distribution population synthesis of an ensemble of evolving close binaries. Results of such simulations definitely depend on the cosmic star formation rate history, which is…
A binary in which a slightly evolved star starts mass transfer to a neutron star can evolve towards ultra-short orbital periods under the influence of magnetic braking. This is called magnetic capture. In a previous paper we showed that…
The first directly observed gravitational wave event, GW150914, featuring the merger of two massive black holes, highlighted the need to determine how these systems of compact remnant binaries are formed. We use the binary population…
X-ray timing of neutron stars in low-mass X-ray binaries (LMXBs) with RXTE has since 1996 revealed several distinct high-frequency phenomena. Among these are oscillations during thermonuclear (type-I) bursts, which (in addition to…
We critically examine the basic paradigm for the origin of the 2-3 hr period gap in cataclysmic variables (CVs). We carry out an extensive population synthesis study of CVs starting from ~ 3 x 10^6 primordial binaries, and evolving some ~ 2…
Sco X-1 is a low-mass X-ray binary (LMXB) that has one of the most precisely determined set of binary parameters such as the mass accretion rate, companions mass ratio and the orbital period. For this system, as well as for a large fraction…
We identify and quantify the set of constraints that neutron star-normal star binaries must satisfy in order to become observable LMXBs. These constraints are related to (i) the thermal and hydrostatic equilibrium of the donors, (ii) the…