J/A+A/626/A127 Barium and related stars and WD companions (Jorissen+, 2019)
Barium and related stars, and their white-dwarf companions. I. Giant stars.
Jorissen A., Boffin H.M.J., Karinkuzhi D., Van Eck S., Escorza A.,
Shetye S., Van Winckel H.
<Astron. Astrophys. 626, A127 (2019)>
=2019A&A...626A.127J 2019A&A...626A.127J (SIMBAD/NED BibCode)
ADC_Keywords: Radial velocities ; Stars, barium ; Stars, S
Keywords: binaries: spectroscopic - white dwarfs - stars: peculiar -
stars: AGB and post-AGB - stars: abundances
Abstract:
This paper provides long-period and revised orbits for barium and S
stars adding to previously published ones. The sample of barium stars
with strong anomalies comprise all such stars present in the Lu et al.
catalogue. We find orbital motion for all barium and extrinsic S stars
monitored. We obtain the longest period known so far for a
spectroscopic binary involving an S star, namely 57 Peg with a period
of the order of 100-500yr. We present the mass distribution for the
barium stars, which ranges from 1 to 3M☉, with a tail extending
up to 5M☉ in the case of mild barium stars. This high-mass tail
comprises mostly high-metallicity objects ([Fe/H]≥-0.1). Mass
functions are compatible with WD companions and we derive their mass
distribution which ranges from 0.5 to 1 Msun. Using the initial -
final mass relationship established for field WDs, we derived the
distribution of the mass ratio q'=MAGB,ini/MBa (where MAGB,ini
is the WD progenitor initial mass, i.e., the mass of the system former
primary component) which is a proxy for the initial mass ratio. It
appears that the distribution of q' is highly non uniform, and
significantly different for mild and strong barium stars, the latter
being characterized by values mostly in excess of 1.4, whereas mild
barium stars occupy the range 1-1.4. We investigate as well the
correlation between abundances, orbital periods, metallicities, and
masses (barium star and WD companion). The 105 orbits of
post-mass-transfer systems presented in this paper pave the way for a
comparison with binary-evolution models.
Description:
Time-dependent radial velocities, mostly from the CORAVEL and HERMES
spectrographs, are provided for 18 barium stars and 15 S stars. They
cover a time span of about 35 years.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 72 32 Star positions (from Simbad)
table2.dat 60 1226 Radial velocities for 17 barium stars
table3.dat 60 907 Radial velocities for 15 S stars
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See also:
J/A+A/626/A128 : Main-sequence and subgiant Barium stars (Escorza+, 2019)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Star name
14- 15 I2 h RAh Simbad Right ascension (J2000.0)
17- 18 I2 min RAm Simbad Right ascension (J2000.0)
20- 25 F6.3 s RAs Simbad Right ascension (J2000.0)
27 A1 --- DE- Simbad Declination sign (J2000.0)
28- 29 I2 deg DEd Simbad Declination (J2000.0)
31- 32 I2 arcmin DEm Simbad Declination (J2000.0)
34- 37 F4.1 arcsec DEs Simbad Declination (J2000.0)
39- 40 A2 --- Type [Ba S] Barium (Ba) of S (S) star
42- 72 A31 --- Names Other names
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Byte-by-byte Description of file: table2.dat table3.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name Star name
14- 25 F12.4 JD JD Julian Date
27- 34 F8.3 km/s RV Radial velocity (without zero-point correction)
36- 40 F5.3 km/s e_RV Uncertainty on radial velocity
42- 56 A15 --- Inst Spectrograph (1)
57- 60 F4.1 km/s Offset Recommended zero-point offset
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Note (1): Possible values are: HERMES, CORAVEL, ELODIE, CAMCOR (Griffin's
Cambridge CORAVEL), GriffinPeery74 (1974Obs....94..188G 1974Obs....94..188G)
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Acknowledgements:
Alain Jorissen, alain.jorissen(at)ulb.ac.be
References:
Escorza et al., Paper II 2091A&A...626A.128E 2091A&A...626A.128E, Cat. J/A+A/626/A128
(End) Alain Jorissen [IAA, Bruxelles], Patricia Vannier [CDS] 27-May-2019