Related papers: New population synthesis model: Preliminary result…
The observed samples of supernovae (SN) and double compact objects (DCOs) provide several critical constraints on population-synthesis models: the parameters of these models must be carefully chosen to reproduce, among other factors, (i)…
In this talk, we present the general principles of binary evolution and give two examples. The first example is the formation of subdwarf B stars (sdBs) and their application to the long-standing problem of ultraviolet excess (also known as…
The evolution of an accreting white dwarf (WD) with strong magnetic field toward a type Ia supernova (SN Ia) may differ from the classical single-degenerate (SD) channel. In this paper, we perform binary population synthesis (BPS)…
I find that Type Ia supernovae (SNe Ia) with bimodal nebular emission profiles occur almost exclusively in massive ($M_\star \gtrsim 10^{11}~M_\odot$) galaxies with low star-formation rates (SFR~$\lesssim 0.5~M_\odot$/yr). The bimodal…
Hot subdwarf stars (sdO/Bs) are evolved core helium-burning stars with very thin hydrogen envelopes, which can be formed by common envelope ejection. Close sdB binaries with massive white dwarf (WD) companions are potential progenitors of…
White dwarfs are the most common endpoints of stellar evolution. They are often found in close binary systems in which the white dwarf is accreting matter from a companion star, either via an accretion disc or channelled along the white…
We perform binary evolution calculations on helium star - carbon-oxygen white dwarf (CO WD) binaries using the stellar evolution code MESA. This single degenerate channel may contribute significantly to thermonuclear supernovae at short…
Subdwarf B stars are a well-known class of hot, low-mass stars thought to be formed through interactions in stellar binary systems. While different formation channels for subdwarf B stars have been studied through a binary population…
In this work, we investigate the impact of tidal torques and mass transfer on the population of double white dwarfs (DWDs) that will be observed with LISA. Starting from a distribution of DWDs at formation predicted by numerical…
Because the majority of massive stars are born as members of close binary systems, populations of massive main-sequence stars contain stellar mergers and products of binary mass transfer. We simulate populations of massive stars accounting…
We have started a large survey for double degenerate (DD) binaries as potential progenitors of type Ia supernovae with the UVES spectrograph at the ESO VLT (ESO SN Ia Progenitor surveY - SPY). About 400 white dwarfs were checked for radial…
Studying the formation and evolution of black hole binaries (BHBs) is essential for the interpretation of current and forthcoming gravitational wave (GW) detections. We investigate the statistics of BHBs that form from isolated binaries, by…
Compact Object Mergers: Population Astrophysics and Statistics (COMPAS; https://compas.science) is a public rapid binary population synthesis code. COMPAS generates populations of isolated stellar binaries under a set of parametrized…
We report results of a population synthesis model that follows the evolution of single and binary stars. In this model we include the 2HeWD merger channel, suggested by Han et al. (2002), for the formation of EHB stars. The physical…
The binary fraction of a stellar population can have pronounced effects on its properties, and in particular the number counts of different massive star types, and the relative subtype rates of the supernovae which end their lives. Here we…
Double white dwarf (double-WD) binaries may merge within a Hubble time and produce high-mass WDs. Compared to other high-mass WDs, the double-WD merger products have higher velocity dispersion because they are older. With the power of Gaia…
Population-synthesis codes are an unique tool to explore the parameter space of massive binary star evolution and binary compact object (BCO) formation. Most population-synthesis codes are based on the same stellar evolution model, limiting…
Stripped-envelope supernovae (SESNe) mark the deaths of massive stars without hydrogen-rich envelopes. Most SESNe likely originate from binary systems where a companion stripped the progenitor of its envelope. Years of HST imaging of nearby…
Recent Gaia astrometry has revealed thousands of main-sequence + white-dwarf binaries (MS+WD) at separations of ~0.1-10 au, including a subset hosting unusually massive (>~0.8 Msun) WDs. We argue that s-process enrichment in the…
Self-lensing (SL) in binary systems has the potential to provide a unique observational window into the Galactic population of compact objects. Using the $\mathtt{startrack}$ and COSMIC population synthesis codes, we investigate how…