J/A+A/665/A150 Rotational properties of Galactic O-type stars (Holgado+ 2022)
The IACOB project.
VII. The rotational properties of Galactic massive O-type stars revisited.
Holgado G., Simon-Diaz S., Herrero A., Barba R.H.
<Astron. Astrophys. 665, A150 (2022)>
=2022A&A...665A.150H 2022A&A...665A.150H (SIMBAD/NED BibCode)
ADC_Keywords: Stars, early-type ; Stars, O ; Rotational velocities ;
Spectroscopy
Keywords: stars: early-type - stars: rotation - techniques: spectroscopic -
catalogs - Galaxy: general
Abstract:
Stellar rotation is of key importance for the formation process,
evolution, and final fate of massive stars.
Performing a reassessment of the empirical rotational properties of Galactic
massive O-type stars using the results from a detailed analysis of
ground-based multi-epoch optical spectra obtained in the framework of the
IACOB & OWN surveys.
Using high-quality optical spectroscopy we establish the velocity
distribution for a sample of 285 apparently single and single line
spectroscopic binary (SB1) Galactic O-type stars. We also make use
of the rest of the parameters from the quantitative spectroscopic
analysis presented in prior IACOB papers (mainly Teff, gravity, and
multiplicity) to study the vsini behavior and evolution from the
comparison of subsamples in different regions of the spectroscopic
HR diagram. Our results are compared to the main predictions --
regarding current and initial rotational velocities -- of two sets
of well-established evolutionary models for single stars, as well
as from population synthesis simulations of massive stars including
binary interaction.
We reassess the known bimodal nature of the vsini distribution, and
find a non negligible difference between the vsini distribution of
single and SB1 stars. We provide empirical evidence supporting the
proposed scenario that the tail of fast rotators is mainly produced by
binary interactions. Stars with extreme rotation (>300km/s) appear as
single stars and located in the lower zone of the sHR. We notice
little rotational braking during the main sequence, in addition to
being independent of mass (and wind strength). The rotation rates of
the youngest observed stars lean to an empirical initial velocity
distribution with <20% of critical velocity. Lastly, there seems to
persist a limit in vsini detection below 40-50km/s, especially in the
upper part of the sHRD, possibly associated with the effect of
microturbulence in the measurement methodology used.
Description:
List of the 285 stars with rotational parameters obtained in this
work. We performed an exhaustive search for spectra of these stars in
modern high resolution spectroscopic databases. The spectrum with best
qual- ity, in terms of signal-to-noise ratio, was considered for the
quantitative spectroscopic analysis and a multi-epoch
characterization.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablef1.dat 79 285 O-type stars considered in this work with
rotational parameters
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See also:
J/A+A/562/A135 : Northern Galactic OB stars vsini (Simon-Diaz+, 2014)
J/A+A/597/A22 : Massive O- and B-type stars velocities (Simon-Diaz+, 2017)
J/A+A/613/A65 : Spectroscopic parameters of O-type stars (Holgado+, 2018)
J/A+A/613/A9 : Extinction towards Galactic O stars (Maiz Apellaniz+, 2018)
J/A+A/638/A157 : O-type stars near ZAMS elusive detection (Holgado+, 2022)
Byte-by-byte Description of file: tablef1.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Target Star name
18- 22 A5 --- SpType Spectral type
24- 38 A15 --- LumClass Luminosity class
40 A1 --- l_Teff Limit flag on Teff
41- 44 F4.1 kK Teff Effective temperature
46 A1 --- l_loggt Limit flag on loggt
47- 50 F4.2 [cm/s2] loggt Gravity corrected from rotational effects
52 A1 --- l_logLsp Limit flag on logLsp
53- 56 F4.2 [Lsun] logLsp Lsp parameter (1)
58- 61 A4 --- Line Line for analysis
63- 65 I3 km/s vsini projected rotational velocity
67- 69 I3 km/s vmacro ?=- Extra-broadening velocity
71- 73 I3 --- Nepochs Number of epochs available
75 A1 --- subsample [abc] Flag ID for subsample clustering
77- 79 A3 --- Notes Multi-epoch notes
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Note (1): Lsp=Teff4/gt, gt=g+gc, gc=(Vrot*sini)2/R*.
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Acknowledgements:
Gonzalo Holgado, gholgado(at)cab.inta-csic.es
References:
Simon-Diaz & Herrero, Paper I 2014A&A...562A.135S 2014A&A...562A.135S, Cat. J/A+A/562/A135
Simon-Diaz et al., Paper II 2014A&A...570L...6S 2014A&A...570L...6S
Simon-Diaz et al., Paper III 2017A&A...597A..22S 2017A&A...597A..22S, Cat, J/A+A/597/A22
Godart et al., Paper IV 2017A&A...597A..23G 2017A&A...597A..23G
Holgado et al., Paper V 2018A&A...613A..65H 2018A&A...613A..65H, Cat. J/A+A/613/A65
Holgado et al., Paper VI 2020A&A...638A.157H 2020A&A...638A.157H, Cat. J/A+A/638/A157
Maiz-Apellaniz & Barba, 2018A&A...613A...9M 2018A&A...613A...9M, Cat. J/A+A/613/A9
(End) Gonzalo Holgado [CAB (INTA-CSIC)], Patricia Vannier [CDS] 08-Jul-2022