Related papers: Localized $^{18}$O production in white dwarf merge…
Helium-core white dwarfs (He WDs) formed through common envelope (CE) evolution offer valuable insight into binary interaction channels and compact remnant formation. Their cooling rates critically impact both detectability and age…
Hydrogen deficient stars include the cool R CrB variable (RCBs) and hydrogen-deficient carbon (HdCs) giants through extreme helium stars (EHes) to the very hot helium-rich subdwarfs (He-sdO and O(He) stars) and white dwarfs. With surfaces…
Helium-rich hot subdwarf stars of spectral type O (He-sdO) are considered prime candidates for stellar merger remnants. Such events should lead to the generation of strong magnetic fields. However, no magnetic He-sdO has yet been…
We analyze the production of the element Cr in galactic chemical evolution (GCE) models using the NuGrid nucleosynthesis yields set. We show that the unusually large [Cr/Fe] abundance at [Fe/H] $\approx 0$ reported by previous studies using…
We discuss a scenario of short Gamma-Ray Bursts (GRBs) following a merger of a massive ONeMg white dwarf (WD) with a CO WD, and an ensuing accretion induced collapse (AIC). An initial system with the primary mass $M_1 \sim 6-10 \, M_\odot$…
Aims: We study single and binary white dwarfs in the inner halo of the Milky Way in order to learn more about the conditions under which the population of halo stars was born, such as the initial mass function (IMF), the star formation…
Classical novae are the result of thermonuclear flashes of hydrogen accreted by CO or ONe white dwarfs, leading eventually to the dynamic ejection of the surface layers. These are observationally known to be enriched in heavy elements, such…
He accretion onto carbon-oxygen white dwarfs (CO WDs) plays a fundamental role when studying the formation of type Ia supernovae (SNe Ia). Employing the MESA stellar evolution code, we calculated the long-term evolution of He-accreting CO…
Gravitational wave detectors are starting to reveal the redshift evolution of the binary black hole (BBH) merger rate, $R_{\mathrm{BBH}}(z)$. We make predictions for $R_{\mathrm{BBH}}(z)$ as a function of black hole mass for systems…
A significant fraction of stars experience close interactions, including collisions resulting from gravitational encounters and mergers within close binary systems. These processes can produce more massive stars that may give rise to…
We present results of a large, high resolution 3D hydrodynamical simulation of the surface layers of a DA white dwarf (WD) with $T_{\rm eff}=11800$ K and $\log(g)=8$ using the ANTARES code, the widest and deepest such simulation to date.…
The diffusion coefficients of neutron rich nuclei in crystallizing white dwarf (WD) stars are essential microphysics input for modeling the evolution of the composition profile. Recently, molecular dynamics simulations have been used to…
The coalescence of massive black hole binaries (BHBs) in galactic mergers is the primary source of gravitational waves (GWs) at low frequencies. Current estimates of GW detection rates for the Laser Interferometer Space Antenna and the…
Neutron star mergers have been long considered as promising sites of heavy $r$-process nucleosynthesis. We overview observational evidence supporting this scenario including: the total amount of $r$-process elements in the Galaxy, extreme…
Mergers of two carbon-oxygen white dwarfs have long been suspected to be progenitors of Type Ia Supernovae. Here we present our modifications to the cosmological smoothed particle hydrodynamics code Gadget to apply it to stellar physics…
We consider the influence of potential quark matter existing at high densities in neutron star interiors on gravitational waves (GW) emitted in a binary neutron star merger event. Two types of equations of state (EoS) at zero temperatures…
Stars with initial masses 7 Msun . MZAMS . 9 Msun reach temperatures high enough to ignite C under degenerate conditions after the end of He-core burning (Garcia-Berro & Iben 1994). These isolated stars are expected to evolve into the…
We calculate the stellar evolution of both white dwarfs (WDs) in AM CVn binaries with orbital periods of $P_{\mathrm{orb}} \approx 5-70$ minutes. We focus on the cases where the donor starts as a $M_{\mathrm{He}} < 0.2 \, M_{\odot}$ Helium…
The gas-phase reaction of $\mathrm{O}+\mathrm{H}_3^+$ has two exothermic product channels, $\mathrm{OH}^+ +\mathrm{H}_2$ and $\mathrm{H}_2\mathrm{O}^+ +\mathrm{H}$. In the present study, we analyze experimental data from a merged-beams…
We present the discovery of the second binary with a Roche lobe-filling hot subdwarf transferring mass to a white dwarf (WD) companion. This 56 minute binary was discovered using data from the Zwicky Transient Facility. Spectroscopic…