scholarly journals Thermal Timescale Mass Transfer in Binary Population Synthesis

2004 ◽  
Vol 194 ◽  
pp. 243-243
Author(s):  
Stephen Justham ◽  
Ulrich Kolb
Keyword(s):  
Mass Transfer ◽  
Stellar Evolution ◽  
State Of The Art ◽  
Nonlinear Behaviour ◽  
Population Synthesis ◽  
Intermediate Mass ◽  
Transfer Rates ◽  
Compact Binary ◽  
Binary Evolution ◽  
Evolution Algorithms

Studies of binary evolution have, until recently, neglected thermal timescale mass transfer (TTMT). Recent work has suggested that this previously poorly studied area is crucial in the understanding of systems across the compact binary spectrum. We use the state-of-the-art binary population synthesis code BiSEPS (Willems and Kolb, 2002, MNRAS 337 1004-1016). However, the present treatment of TTMT is incomplete due to the nonlinear behaviour of stars in their departure from gravothermal ‘equilibrium’. Here we show work that should update the ultrafast stellar evolution algorithms within BiSEPS to make it the first pseudo-analytic code that can follow TTMT properly. We have generated fits to a set of over 300 Case B TTMT sequences with a range of intermediate-mass donors. These fits produce very good first approximations to both HR diagrams and mass-transfer rates (see figures 1 and 2), which we later hope to improve and extend. They are already a significant improvement over the previous fits.

scholarly journals Algols as Limits on Binary Evolution Scenarios

1989 ◽  
Vol 107 ◽  
pp. 155-164
Author(s):  
M.S. Hjellming
Keyword(s):  
Mass Transfer ◽  
Mass Loss ◽  
Initial Mass ◽  
Transfer Rates ◽  
Successful Transition ◽  
Evolutionary State ◽  
Mass Ratios ◽  
Binary Evolution ◽  
Do So

AbstractEvolutionary scenarios must account for Algol binaries surviving their first phase of mass transfer. The outcome of this phase is dependent upon the rapidity of the initial mass transfer, which can be estimated by calculating the radial reponse of potential progenitors to mass loss. Limits on the donor’s evolutionary state, and its companion mass, can be placed on systems which would transfer mass on a thermal or dynamical timescale. Slower mass transfer rates are necessary for the successful transition to an Algol. Considering 1.5 and 5.0 M⊙ models, the former succeed in case A and Br systems, while the latter can do so only in case A systems. To evolve into an Algol binary, all systems seem to require initial mass ratios near one.

scholarly journals Population Synthesis of Type Ia SNe: Constraining Free Parameters from Observations

2011 ◽  
Vol 7 (S281) ◽  
pp. 240-243
Author(s):  
Maxwell Moe ◽  
Rosanne Di Stefano
Keyword(s):  
Mass Transfer ◽  
First Principles ◽  
Type Ia Supernovae ◽  
Population Synthesis ◽  
Common Envelope ◽  
Tidal Interactions ◽  
Type Ia ◽  
Free Parameters ◽  
Binary Evolution ◽  
Ia Supernovae

AbstractComputing the rate of Type Ia supernovae (SNe Ia) from first principles is difficult because there are large uncertainties regarding several key binary processes such as common envelope evolution, tidal interactions, and the efficiency of mass transfer. Fortunately, a range of observational parameters of binaries in intermediate stages of evolution can help us model these processes in a way that is likely to mirror the true binary evolution. We discuss how this observationally-motivated approach may have the effect of increasing the predicted rate of single degenerate progenitors of SNe Ia, while simultaneously decreasing the number of double degenerate progenitors.

scholarly journals Contamination of RR Lyrae stars from Binary Evolution Pulsators

2015 ◽  
Vol 5 (1) ◽  
pp. 24-28
Author(s):  
P. Karczmarek
Keyword(s):  
Mass Transfer ◽  
Binary System ◽  
Synthesis Method ◽  
Population Synthesis ◽  
Rr Lyrae Stars ◽  
Rr Lyrae ◽  
Low Mass ◽  
Binary Evolution ◽  
Lyrae Stars ◽  
Range Of Values

A Binary Evolution Pulsator (BEP) is a low-mass (0.26 𝔐☉) member of a binary system, which pulsates as a result of a former mass transfer to its companion. The BEP mimics RR Lyrae-type pulsations, but has completely different internal structure and evolution history. Although there is only one known BEP (OGLE-BLG-RRLYR-02792), it has been estimated that approximately 0.2% of objects classified as RR Lyrae stars can be undetected Binary Evolution Pulsators. In the present work, this contamination value is re-evaluated using the population synthesis method. The output falls inside a range of values dependent on tuning the parameters in the StarTrack code, and varies from 0.06% to 0.43%.

scholarly journals The impact of close binary evolution on the properties of the WR-bump emission lines of Wolf-Rayet galaxies

2003 ◽  
Vol 212 ◽  
pp. 576-577
Author(s):  
Joris Van Bever ◽  
Dany Vanbeveren
Keyword(s):  
Mass Transfer ◽  
Neutron Stars ◽  
Supernova Explosion ◽  
Emission Lines ◽  
Close Binary ◽  
Population Synthesis ◽  
Common Envelope ◽  
Solar Metallicity ◽  
Binary Evolution ◽  
The Impact

We present the results of a study on the behaviour of the blue and red WR emission bumps (around 4650Å and 5808Å) and of the nebular contribution to He ii λ4686 in evolving young starburst regions (such as Wolf-Rayet galaxies), containing a non-negligible binary population. Calculations were made for solar metallicity and 1/20 solar. The population synthesis program uses an extended library of stellar evolutionary tracks of single stars and binaries, computed using the most recent stellar wind mass loss rates during RSG, LBV and WR stages. In the case of binaries, we account in detail for the effects of Roche lobe overflow, mass transfer and mass accretion, common envelope evolution, the spiral-in process, asymmetric kicks to neutron stars as a result of their supernova explosion, etc. This research is part of a more extensive project to explore every possible impact of massive binaries on stellar populations.

scholarly journals Exploring the Parameter Space of Compact Binary Population Synthesis

2016 ◽  
Vol 12 (S325) ◽  
pp. 46-50 ◽  
Author(s):  
Jim W. Barrett ◽  
Ilya Mandel ◽  
Coenraad J. Neijssel ◽  
Simon Stevenson ◽  
Alejandro Vigna-Gómez
Keyword(s):  
Gravitational Wave ◽  
Gaussian Process ◽  
Parameter Space ◽  
Gaussian Process Regression ◽  
Compact Object ◽  
Population Synthesis ◽  
Preliminary Results ◽  
Compact Binary ◽  
Binary Evolution

AbstractAs we enter the era of gravitational wave astronomy, we are beginning to collect observations which will enable us to explore aspects of astrophysics of massive stellar binaries which were previously beyond reach. In this paper we describe COMPAS (Compact Object Mergers: Population Astrophysics and Statistics), a new platform to allow us to deepen our understanding of isolated binary evolution and the formation of gravitational-wave sources. We describe the computational challenges associated with their exploration, and present preliminary results on overcoming them using Gaussian process regression as a simulation emulation technique.

scholarly journals Evidence for reduced magnetic braking in polars from binary population models

2019 ◽  
Vol 491 (4) ◽  
pp. 5717-5731 ◽  
Author(s):  
Diogo Belloni ◽  
Matthias R Schreiber ◽  
Anna F Pala ◽  
Boris T Gänsicke ◽  
Mónica Zorotovic ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Cataclysmic Variables ◽  
Sloan Digital Sky Survey ◽  
Population Synthesis ◽  
Homogeneous Sample ◽  
Magnetic Systems ◽  
Transfer Rates ◽  
Sky Survey ◽  
Magnetic Braking ◽  
Magnetic Cataclysmic Variables

ABSTRACT We present the first population synthesis of synchronous magnetic cataclysmic variables, called polars, taking into account the effect of the white dwarf (WD) magnetic field on angular momentum loss. We implemented the reduced magnetic braking (MB) model proposed by Li, Wu & Wickramasinghe into the Binary Stellar Evolution (bse) code recently calibrated for cataclysmic variable (CV) evolution. We then compared separately our predictions for polars and non-magnetic CVs with a large and homogeneous sample of observed CVs from the Sloan Digital Sky Survey. We found that the predicted orbital period distributions and space densities agree with the observations if period bouncers are excluded. For polars, we also find agreement between predicted and observed mass transfer rates, while the mass transfer rates of non-magnetic CVs with periods ≳3 h drastically disagree with those derived from observations. Our results provide strong evidence that the reduced MB model for the evolution of highly magnetized accreting WDs can explain the observed properties of polars. The remaining main issues in our understanding of CV evolution are the origin of the large number of highly magnetic WDs, the large scatter of the observed mass transfer rates for non-magnetic systems with periods ≳3 h, and the absence of period bouncers in observed samples.

The Initial–Final Mass Relation for Close Low–Intermediate-Mass Binaries (Non-conservative Case)

2002 ◽  
Vol 187 ◽  
pp. 291-296
Author(s):  
Xuefei Chen ◽  
Zhanwen Han
Keyword(s):  
Stellar Evolution ◽  
Initial Mass ◽  
Mass Relation ◽  
Centre Of Mass ◽  
Mass Ratio ◽  
Intermediate Mass ◽  
Primary Mass ◽  
Binary Evolution ◽  
Hertzsprung Gap ◽  
Remnant Mass

AbstractEmploying Eggleton’s stellar evolution code, we carry out 150 runs of non-conservative Population I binary evolution calculations with the initial primary mass between 1 and 8 M⊙, the initial mass ratio q = M1/M2 between 1.1 and 4 and the onset of Roche lobe overflow (RLOF) at the early, middle or late Hertzsprung gap. We assume that 50 per cent of the mass lost from the primary during the RLOF is accreted on to the secondary, the other 50 per cent is lost from the system, carrying away the same specific angular momentum as the centre of mass of the primary. We find that the remnant mass depends on when the RLOF begins in the Hertzsprung-gap and the dependency increases with the primary mass. The remnant mass, however, does not depend much on the initial mass ratio, as compared to conservative cases. For qi = 1.1, we fit a formula for the remnant mass as a function of the initial mass M1i of the primary and the radius of the primary at the onset of RLOF with an error less than 2.61 per cent.

scholarly journals Multiple Stellar Evolution: a population synthesis algorithm to model the stellar, binary, and dynamical evolution of multiple-star systems

2021 ◽  
Vol 502 (3) ◽  
pp. 4479-4512
Author(s):  
Adrian S Hamers ◽  
Antti Rantala ◽  
Patrick Neunteufel ◽  
Holly Preece ◽  
Pavan Vynatheya
Keyword(s):  
Mass Transfer ◽  
Stellar Evolution ◽  
Stellar System ◽  
Dynamical Evolution ◽  
Compact Object ◽  
Population Synthesis ◽  
Efficient Computation ◽  
Single Star ◽  
Multiple Star ◽  
Dynamic Switching

ABSTRACT In recent years, observations have shown that multiple-star systems such as hierarchical triple and quadruple-star systems are common, especially among massive stars. They are potential sources of interesting astrophysical phenomena such as compact object mergers, leading to supernovae, and gravitational wave events. However, many uncertainties remain in their often complex evolution. Here, we present the population synthesis code Multiple Stellar Evolution (mse), designed to rapidly model the stellar, binary, and dynamical evolution of multiple-star systems. mse includes a number of new features not present in previous population synthesis codes: (1) an arbitrary number of stars, as long as the initial system is hierarchical, (2) dynamic switching between secular and direct N-body integration for efficient computation of the gravitational dynamics, (3) treatment of mass transfer in eccentric orbits, which occurs commonly in multiple-star systems, (4) a simple treatment of tidal, common envelope, and mass transfer evolution in which the accretor is a binary instead of a single star, (5) taking into account planets within the stellar system, and (6) including gravitational perturbations from passing field stars. mse, written primarily in the C++ language, will be made publicly available and has few prerequisites; a convenient python interface is provided. We give a detailed description of MSE and illustrate how to use the code in practice. We demonstrate its operation in a number of examples.

scholarly journals The expansion of stripped-envelope stars: Consequences for supernovae and gravitational-wave progenitors

2020 ◽  
Vol 637 ◽  
pp. A6 ◽  
Author(s):  
E. Laplace ◽  
Y. Götberg ◽  
S. E. de Mink ◽  
S. Justham ◽  
R. Farmer
Keyword(s):  
Mass Transfer ◽  
Neutron Star ◽  
Gravitational Wave ◽  
Compact Objects ◽  
Population Synthesis ◽  
Outer Envelope ◽  
Low Metallicity ◽  
Binary Evolution ◽  
Ultimate Fate ◽  
High Metallicity

Massive binaries that merge as compact objects are the progenitors of gravitational-wave sources. Most of these binaries experience one or more phases of mass transfer, during which one of the stars loses all or part of its outer envelope and becomes a stripped-envelope star. The evolution of the size of these stripped stars is crucial in determining whether they experience further interactions and understanding their ultimate fate. We present new calculations of stripped-envelope stars based on binary evolution models computed with MESA. We use these to investigate their radius evolution as a function of mass and metallicity. We further discuss their pre-supernova observable characteristics and potential consequences of their evolution on the properties of supernovae from stripped stars. At high metallicity, we find that practically all of the hydrogen-rich envelope is removed, which is in agreement with earlier findings. Only progenitors with initial masses below 10 M⊙ expand to large radii (up to 100 R⊙), while more massive progenitors remain compact. At low metallicity, a substantial amount of hydrogen remains and the progenitors can, in principle, expand to giant sizes (> 400 R⊙) for all masses we consider. This implies that they can fill their Roche lobe anew. We show that the prescriptions commonly used in population synthesis models underestimate the stellar radii by up to two orders of magnitude. We expect that this has consequences for the predictions for gravitational-wave sources from double neutron star mergers, particularly with regard to their metallicity dependence.

Sign in / Sign up

Export Citation Format

Share Document