J/A+A/669/A45 Mass transfer from post-main-sequence donor stars (Temmink+, 2023)
Coping with loss.
Stability of mass transfer from post-main-sequence donor stars.
Temmink K.D., Pols O.R., Justham S., Istrate A.G., Toonen S.
<Astron. Astrophys. 669, A45 (2023)>
=2023A&A...669A..45T 2023A&A...669A..45T (SIMBAD/NED BibCode)
+2025A&A...694C...8T 2025A&A...694C...8T
ADC_Keywords: Models, evolutionary ; Stars, standard ; Mass loss
Keywords: binaries: close - stars: low-mas - stars: evolution - stars: interiors
Abstract:
The stability of mass transfer is critical in determining pathways
towards various kinds of compact binaries, such as compact
main-sequence white-dwarf binaries, and transients, such as double
white-dwarf mergers and luminous red novae. Despite its importance,
only very few systematic studies of the stability of mass transfer
exist. Using the 1D stellar evolution code MESA, we study the
behaviour of mass-losing post-main-sequence donor stars with masses
between 1M☉ and 8M☉ in binaries, without assuming that the
donor star responds to mass loss adiabatically. We treat the accretor
as a point mass, which we do not evolve, and assume the mass transfer
is conservative. We find that the criterion that best predicts the
onset of runaway mass transfer is based on the transition to an
effectively adiabatic donor response to mass loss. We find that the
critical mass ratio qqad∼0.25 for stars crossing the Hertzsprung
gap, while for convective giants qqad decreases from ∼1 at the base
of the RGB to ∼0.1 at the onset of thermal pulses on the AGB. An
effectively adiabatic response of the donor star only occurs at a very
high critical mass-transfer rate due to the short local thermal
timescale in the outermost layers of a red giant. For q>qqad mass
transfer is self-regulated, but for evolved giants the resulting
mass-transfer rates can be so high that the evolution becomes
dynamical and/or the donor can overflow its outer lobe. Our results
indicate that mass transfer is stable for a wider range of binary
parameter space than typically assumed in rapid binary population
synthesis and found in recent similar studies. Moreover, we find a
systematic dependence of the critical mass ratio on the donor star
mass and radius which may have significant consequences for
predictions of post-mass-transfer populations.
Description:
Aspects of binary stellar evolution pertaining to the stability of
mass transfer are presented. This includes the location of the
boundary between stable and unstable mass transfer according to three
different physical criteria in the form of a critical mass ratio q
(q=Ma/Md), above which mass transfer is expected to be stable and
self-regulating, and a critical mass transfer rate, above which the
donor star transitions to an adiabatic response, resulting in a mass
transfer instability in our simulations. Further properties presented
include the location of our simulation grid points in donor mass and
radius at the onset of RLOF, as well as quantities summarizing the
mass transfer, such as the global KH mass transfer rate, and the
average and peak mass transfer rates found in our calculations.
Corrigendum:
We have discovered that an inadvertent oversight was made in our
numerical setup, for which we sincerely apologize. To summarize, the
mass transfer was not fully conservative, as was intended, meaning
that the actual numerical settings that were used deviate from what is
stated in our methodology. We have investigated the effects of this
oversight and have found that our published results are not
significantly affected.
In the corrected table B2, the critical mass ratios have been
re-calculated with the correct numerical settings that correspond to
what is written in the original published work.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tableb1.dat 48 1404 Key aspects of the mass-transfer evolution in
our binary models
tableb2.dat 43 117 Tabulation of our main results
(corrected version from erratum, 11/02/2025)
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 3 F3.1 Msun MassZAMS ZAMS mass of donor star
5- 6 I2 --- Model Radial grid point number
8- 18 F11.9 [Rsun] logR-RLOF Donor radius at Roche lobe overflow
20- 22 F3.1 --- qRLOF Mass ratio at Roche lobe overflow
24- 35 F12.9 [Msun/yr] log-max-Mdot ? Maximum mass transfer rate (1)
37- 48 F12.9 [Msun/yr] log-ave-Mdot ? Mass-averaged mass transfer rate (1)
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Note (1): For binary systems that experience unstable mass transfer, we have
not calculated the mass-averaged and maximum mass transfer rates.
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Byte-by-byte Description of file: tableb2.dat
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Bytes Format Units Label Explanations
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1- 3 F3.1 Msun MassZAMS ZAMS mass of donor star
5- 6 I2 --- Model Radial grid point number
8- 18 F11.9 [Rsun] logR-RLOF Donor radius at Roche lobe overflow
20- 30 F11.9 Msun MassRLOF Donor mass at Roche lobe overflow
32- 36 F5.3 --- qqad Quasi-adiabatic critical mass ratio
38- 43 F6.4 --- dqqad Uncertainty on qqad
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Acknowledgements:
Karel Temmink, Karel.Temmink(at)ru.nl
History:
05-Jan-2023: on-line version
11-Feb-2025: corrected table B2 (from erratum)
(End) Patricia Vannier [CDS] 25-Nov-2022