J/A+A/550/A109 VLT-FLAMES Tarantula Survey: vsini measures (Dufton+ 2013)
The VLT-FLAMES Tarantula Survey.
X: Evidence for a bimodal distribution of rotational velocities for the single
early B-type stars.
Dufton P.L., Langer N., Dunstall P.R., Evans C.J., BrottI., de Mink S.E.,
HowarthI.D., Kennedy M., McEvoy C., Potter A.T., Ramirez-Agudelo O.H.,
Sana H., Simon-Diaz S., Taylor W., Vink J.S.
<Astron. Astrophys. 550, A109 (2013)>
=2013A&A...550A.109D 2013A&A...550A.109D
ADC_Keywords: Magellanic Clouds ; Stars, B-type ; Rotational velocities
Keywords: stars: early-type - Magellanic Clouds - stars: rotation -
stars: massive - stars: magnetic field
Abstract:
Projected rotational velocities (vsini) have been estimated for 334
targets in the VLT-FLAMES Tarantula survey that do not manifest
significant radial velocity variations and are not supergiants. They
have spectral types from approximately O9.5 to B3. The estimates have
been analysed to infer the underlying rotational velocity
distribution, which is critical for understanding the evolution of
massive stars.
Projected rotational velocities were deduced from the Fourier
transforms of spectral lines, with upper limits also being obtained
from profile fitting. For the narrower lined stars, metal and
non-diffuse helium lines were adopted, and for the broader lined
stars, both non-diffuse and diffuse helium lines; the estimates
obtained using the different sets of lines are in good agreement. The
uncertainty in the mean estimates is typically 4% for most targets.
The iterative deconvolution procedure of Lucy has been used to deduce
the probability density distribution of the rotational velocities.
Projected rotational velocities range up to approximately 450km/s and
show a bi-modal structure. This is also present in the inferred
rotational velocity distribution with 25% of the sample having
0≥ve≥100km/s and the high velocity component having
ve∼250km/s. There is no evidence from the spatial and radial
velocity distributions of the two components that they represent
either field and cluster populations or different episodes of star
formation. Be-type stars have also been identified.
Description:
Rotational velocity estimates are presented for (near) main sequence
B-type stars that were observed in the VFTS and that are believed to
be single. For each star, estimates are given from different lines are
given deduced using both profile fitting (PF) and Fourier Transform
(FT) methodologies, together with line central depths (CD). Also
listed for each star are the means from the two methodologies,
together with standard deviation for the FT estimates.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 139 116 Narrow lined stars results, from both profile
fitting (PF) and Fourier Transform (FT) methodologies
table4.dat 115 225 Broad line stars results, from both profile
fitting (PF) and Fourier Transform (FT) methodologies
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See also:
J/A+A/530/A108 : VLT-FLAMES Tarantula Survey (Evans+, 2011)
J/A+A/550/A107 : RV catalogue of O stars in 30 Doradus (Sana+, 2013)
J/A+A/550/A108 : DIB in VLT-FLAMES Tarantula Survey (van Loon+, 2012)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- VFTS Star number
5 I1 --- u_VFTS [1]? 1 indicates status uncertain
7- 9 I3 km/s PF4120 ? HeI 4120Å vsini from PF methodology
11- 13 I3 km/s FT4120 ? HeI 4120Å vsini from FT methodology
15- 17 I3 % CD4120 ? HeI 4120Å central depth from PF methodology
19- 21 I3 km/s PF4169 ? HeI 4169Å vsini from PF methodology
23- 25 I3 km/s FT4169 ? HeI 4169Å vsini from FT methodology
27- 29 I3 % CD4169 ? HeI 4169Å central depth from PF methodology
31- 33 I3 km/s PF4267 ? CII 4267Å vsini from PF methodology
35- 37 I3 km/s FT4267 ? CII 4267Å vsini from FT methodology
39- 41 I3 % CD4267 ? CII 4267Å central depth from PF methodology
43- 45 I3 km/s PF4437 ? HeI 4437Å vsini from PF methodology
47- 49 I3 km/s FT4437 ? HeI 4437Å vsini from FT methodology
51- 53 I3 % CD4437 ? HeI 4437Å central depth from PF methodology
55- 57 I3 km/s PF4481 ? MgII 4481Å vsini from PF methodology
59- 61 I3 km/s FT4481 ? MgII 4481Å vsini from FT methodology
63- 65 I3 % CD4481 ? MgII 4481Å central depth from PF methodology
67- 69 I3 km/s PF4552 ? SiIII 4552Å vsini from PF methodology
71- 73 I3 km/s FT4552 ? SiIII 4552Å vsini from FT methodology
75- 77 I3 % CD4552 ? SiIII 4552Å central depth from PF methodology
79- 81 I3 km/s PF4567 ? SiIII 4567Å vsini from PF methodology
83- 85 I3 km/s FT4567 ? SiIII 4567Å vsini from FT methodology
87- 89 I3 % CD4567 ? SiIII 4567Å central depth from PF methodology
91- 93 I3 km/s PF4574 ? SiIII 4574Å vsini from PF methodology
95- 97 I3 km/s FT4574 ? SiIII 4574Å vsini from FT methodology
99-101 I3 % CD4574 ? SiIII 4574Å central depth from PF methodology
103-105 I3 km/s PF4661 ? OII 4661Å vsini from PF methodology
107-109 I3 km/s FT4661 ? OII 4661Å vsini from FT methodology
111-113 I3 % CD4661 ? OII 4661Å central depth from PF methodology
115-117 I3 km/s PF4713 ? HeI 4713Å vsini from PF methodology
119-121 I3 km/s FT4713 ? HeI 4713Å vsini from FT methodology
123-125 I3 % CD4713 ? HeI 4713Å central depth from PF methodology
128-130 I3 km/s FTM ? Weighted mean of the FT estimates;
Value of 40km/s is an upper limit
132-134 I3 km/s e_FTM ? Standard deviation of the FT estimates.
Null value: FTM is either an upper value or
assigned to a 40km/s bin
137-139 I3 km/s PFM ? Unweighted mean of the PF estimates
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- VFTS Star number
5 I1 --- u_VFTS [1]? 1 indicates status uncertain
7- 9 I3 km/s PF4009 ? HeI 4009Å vsini from PF methodology
11- 13 I3 km/s FT4009 ? HeI 4009Å vsini from FT methodology
15- 17 I3 % CD4009 ? HeI 4009Å central depth from PF methodology
19- 21 I3 km/s PF4026 ? HeI 4026Å vsini from PF methodology
23- 25 I3 km/s FT4026 ? HeI 4026Å vsini from FT methodology
27- 29 I3 % CD4026 ? HeI 4026Å central depth from PF methodology
31- 33 I3 km/s PF4120 ? He 4120Å vsini from PF methodology
35- 37 I3 km/s FT4120 ? He 4120Å vsini from FT methodology
39- 41 I3 % CD4120 ? HeI 4120Å central depth from PF methodology
43- 45 I3 km/s PF4143 ? HeI 4143Å vsini from PF methodology
47- 49 I3 km/s FT4143 ? HeI 4143Å vsini from FT methodology
51- 53 I3 % CD4143 ? HeI 4143Å central depth from PF methodology
55- 57 I3 km/s PF4387 ? HeI 4387Å vsini from PF methodology
59- 61 I3 km/s FT4387 ? HeI 4387Å vsini from FT methodology
63- 65 I3 % CD4387 ? HeI 4387Å central depth from PF methodology
67- 69 I3 km/s PF4471 ? HeI 4471Å vsini from PF methodology
71- 73 I3 km/s FT4471 ? HeI 4471Å vsini from FT methodology
75- 77 I3 % CD4471 ? HeI 4471Å central depth from PF methodology
79- 81 I3 km/s PF4713 ? HeI 4713Å vsini from PF methodology
83- 85 I3 km/s FT4713 ? HeI 4713Å vsini from FT methodology
87- 89 I3 % CD4713 ? HeI 4713Å central depth from PF methodology
91- 93 I3 km/s PF4921 ? HeI 4921Å vsini from PF methodology
95- 97 I3 km/s FT4921 ? HeI 4921Å vsini from FT methodology
99-101 I3 % CD4921 ? HeI 4921Å central depth from PF methodology
104-106 I3 km/s FTM ? Weighted mean of the FT estimates
108-110 I3 km/s e_FTM ? Standard deviation of the FT estimates
Null value: FTM assigned to a 40km/s bin
113-115 I3 km/s PFM ? Unweighted mean of the PF estimates
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Acknowledgements:
Philip Dufton, p.dufton(at)qub.ac.uk
References:
Evans et al., Paper I 2011A&A...530A.108E 2011A&A...530A.108E, Cat. J/A+A/530/A108
Taylor et al., Paper II 2011A&A...530L..10T 2011A&A...530L..10T
Bestenlehner et al., Paper III 2011A&A...530L..14B 2011A&A...530L..14B
Bressert et al., Paper IV 2012A&A...542A..49B 2012A&A...542A..49B
Dunstall et al., Paper V 2012A&A...542A..50D 2012A&A...542A..50D
Henault-Brunet et al., Paper VI 2012A&A...545L...1H 2012A&A...545L...1H
Henault-Brunet et al., Paper VII 2012A&A...546A..73H 2012A&A...546A..73H
Sana et al., Paper VIII 2013A&A...550A.107S 2013A&A...550A.107S, Cat. J/A+A/550/A107
van Loon et al., Paper IX 2012A&A...550A.108V 2012A&A...550A.108V, Cat. J/A+A/550/A108
(End) P. Dufton [Queens Univ. of Belfast], P. Vannier [CDS] 06-Dec-2012