J/ApJ/899/132 Adiabatic Mass Loss in Binary Stars. III. (Ge+, 2020)
Adiabatic Mass Loss in Binary Stars.
III. From the Base of the Red Giant Branch to the Tip of the Asymptotic Giant
Branch.
Ge H., Webbink R.F., Chen X., Han Z.
<Astrophys. J., 899, 132 (2020)>
=2020ApJ...899..132G 2020ApJ...899..132G
ADC_Keywords: Models, evolutionary; Stars, masses; Stars, double and multiple;
Mass loss; Photometry, infrared
Keywords: Stellar evolution ; Stellar mass loss ; Close binary stars ;
Common envelope evolution ; Stellar interiors
Abstract:
The distinguishing feature of the evolution of close binary stars is
the role played by the mass exchange between the component stars.
Whether or not the mass transfer is dynamically stable is one of the
essential questions in binary evolution. In the limit of extremely
rapid mass transfer, the response of a donor star in an interacting
binary becomes asymptotically one of adiabatic expansion. We use the
adiabatic mass-loss model to systematically survey the thresholds for
dynamical timescale mass transfer over the entire span of possible
donor star evolutionary states. We also simulate mass-loss process
with isentropic envelopes, the specific entropy of which is fixed to
be that at the base of the convective envelope, to artificially mimic
the effect of such mass loss in superadiabatic surface convection
regions, where the adiabatic approximation fails. We illustrate the
general adiabatic response of 3.2M☉ donor stars at different
evolutionary stages. We extend our study to a grid of donor stars with
different masses (from 0.1 to 100 M☉ with Z=0.02) and at different
evolutionary stages. We proceed to present our criteria for
dynamically unstable mass transfer in both tabular and graphical
forms. For red giant branch (RGB) and asymptotic giant branch (AGB)
donors in systems with such mass ratios, they may have convective
envelopes deep enough to evolve into common envelopes on a thermal
timescale, if the donor star overfills its outer Lagrangian radius.
Our results show that the RGB and AGB stars tend to be more stable
than previously believed, and this may be helpful to explain the
abundance of observed post-AGB binary stars with an orbital period of
around 1000 days.
Description:
In Paper II, we surveyed the adiabatic responses of Population I
(Z=0.02) stars spanning a full range of stellar mass and evolutionary
stages from the zero-age main sequence (ZAMS) to the terminal main
sequence (TMS), through the Hertzsprung gap (HG) to the base of the
giant branch (BGB). In the present paper, we update and extend our
survey of adiabatic mass loss to late phases of stellar evolution,
from the ZAMS through the main sequence (MS), HG, RGB, and AGB, up to
the exhaustion of the hydrogen-rich envelopes, carbon ignition, or
core-collapse, as the case may be.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 82 1567 Interior properties of initial models
table2.dat 83 1567 Global properties of initial models
table3.dat 112 1567 Thresholds for conservative dynamical time scale
mass transfer
--------------------------------------------------------------------------------
See also:
J/MNRAS/403/1213 : Tracers of stellar mass-loss. I. (Gonzalez-Lopezlira+, 2010)
J/ApJ/753/71 : Mass-loss return from LMC evolved stars. VI. (Riebel+, 2012)
J/A+A/556/A38 : Period-mass-loss rate relation of Miras (Uttenthaler, 2013)
J/ApJ/812/40 : Adiabatic mass loss in binary stars. II. (Ge+, 2015)
J/MNRAS/470/3765 : Mass-loss rates in LMC and SMC O stars (Massa+, 2017)
J/A+A/616/A58 : Variability of the adiabatic parameter (de Avillez+, 2018)
J/ApJ/856/170 : Tracers of stellar mass-loss. II. (Gonzalez-Lopezlira, 2018)
J/A+A/622/A120 : Mass loss from Miras with and without Tc (Uttenthaler, 2019)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 F7.3 Msun Mass [0.1/100] Model mass
9- 10 I2 --- k [1/71] Mass loss sequence number
12- 20 F9.6 [yr] Age [0/13] Log age (1)
22- 28 F7.4 Msun MassCE [0/31] Convective envelope mass (2)
30- 36 F7.4 Msun MassC [0/85] Core mass (3)
38- 44 F7.4 Msun MassIC [0/40] Inner core mass (4)
46- 52 F7.3 --- psic [-8/206] Central electron chemical potential (5)
54- 58 F5.3 [g/cm3] rhoc [0.1/9.4] Log central density
60- 64 F5.3 [K] Tc [6.6/9] Log central temperature
66- 70 F5.3 --- Hc [0/0.7] Central hydrogen abundance (6)
72- 76 F5.3 --- Hec [0/1] Central helium abundance (6)
78- 82 F5.3 --- Hs [0.1/0.8] Surface hydrogen abundance (6)
--------------------------------------------------------------------------------
Note (1): Measured from the zero-age main sequence model
(excluding pre-main-sequence evolution).
Note (2): This refers to the mass depth of the base of the outermost
convection zone.
Note (3): This refers to the mass coordinate at which the helium abundance is
halfway between the surface helium abundance and the maximum helium
abundance in the stellar interior.
Note (4): the mass coordinate at which the helium abundance is halfway between
the maximum helium abundance in the stellar interior and the minimum
helium abundance interior to that maximum; in the absence of
measurable helium depletion in the hydrogen-exhaused core, MassIC is
set to a default value of zero.
Note (5): Divided by kTc. Measures the degree of electron degeneracy (psic>0).
Note (6): Fraction by mass.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.4 Msun Mass [0.1/100] Model mass
10- 11 I2 --- k [1/71] Mass loss sequence number
13- 19 F7.4 [Rsun] Rad [-0.9/3.6] Log radius
21- 26 F6.4 [K] Teff [3.4/4.7] Log effective temperature
28- 34 F7.4 [Lsun] Lum [-3.1/6.5] Log stellar Luminosity
36- 42 F7.3 [Lsun] LumH [-17.4/6.5] Log hydrogen-burning luminosity
44- 50 F7.3 [Lsun] LumHe [-39/6.3]?=-99 Log helium-burning luminosity
52- 58 F7.3 [Lsun] LumZ [-41.3/5.8]?=-99 Log heavy-element burning
luminosity
60- 65 F6.3 [Lsun] Lumnu [-4.8/6.8] Log neutrino luminosity
67- 67 A1 --- f_Lumnu [*] Flag on Lumnu (1)
69- 74 F6.3 [Lsun] Lumth [-7.7/6.7] Log gravothermal luminosity
76- 76 A1 --- f_Lumth [*] Flag on Lumth (1)
78- 83 F6.4 --- I/MR2 [0/0.3] Dimensionless moment of inertia
--------------------------------------------------------------------------------
Note (1): Flag as follows:
* = Indicates a negative contribution to the net stellar luminosity
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 F7.3 Msun Mass [0.1/100] Initial mass model
9- 10 I2 --- k [1/71] Mass loss sequence number
12- 18 F7.4 [Rsun] Rad [-0.9/3.6] Log initial radius (1)
20- 26 F7.4 Msun MKH [0.07/70.15]?=-9.99 Mass threshold (2)
28- 34 F7.4 [Rsun] RKH [-1.8/2.6]?=-9.99 Log Roche lobe radius (2)
36- 42 F7.4 [Rsun] R*KH [-1.8/3.61]?=-9.99 Log stellar radius (2)
44- 51 F8.3 --- zetaad [-2.635/8700]?=-9.99 Critical mass-radius
exponent for dynamical time scale mass
53- 60 F8.3 --- qad [-0.433/4400]?=-9.99 Critical mass ratio for
dynamical time scale (conservative) mass
transfer (1)
62- 68 F7.4 [-] Dexp [0/1.6]?=-9.99 Log superadiabatic expansion
factor (3)
70- 76 F7.4 Msun MKHic [0.07/76.07]?=-9.99 Mass threshold (4)
78- 84 F7.4 [Rsun] RKHic [-1.7/2.6]?=-9.99 Log Roche lobe radius (4)
86- 92 F7.4 [Rsun] R*KHic [-1.7/3.7]?=-9.99 Log stellar radius (4)
94-102 F9.3 --- zetaadic [-0.4/52000]?=-9.99 Critical mass-radius
exponent for dynamical time scale mass transfer
(3)
104-112 F9.3 --- qadic [0.6/26000]?=-9.99 Critical mass ratio for
dynamical time scale (conservative) mass
transfer (3)
--------------------------------------------------------------------------------
Note (1): For models with standard mixing-length convective envelopes.
Note (2): For models with standard mixing-length convective envelopes
at which Mdot=-Mi/τKH where Mi is the initial mass.
Note (3): For models with artificially isentropic convective envelopes.
Note (4): For models with artificially isentropic convective envelopes
at which Mdot=-Mi/τKH where Mi is the initial mass.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Ge et al. Paper I: 2010ApJ...717..724G 2010ApJ...717..724G
Ge et al. Paper II: 2015ApJ...812...40G 2015ApJ...812...40G cat. J/ApJ/812/40
(End) Prepared by [AAS], Coralie Fix [CDS], 26-Oct-2021