J/A+A/574/A13 VFTS. B-type stars classification and RV (Evans+, 2015)
The VLT-FLAMES Tarantula Survey.
XVIII. Classifications and radial velocities of the B-type stars.
Evans C.J., Kennedy M.B., Dufton P.L., Howarth I.D., Walborn N.R.,
Markova N., Clark J.S., de Mink S.E., de Koter A., Dunstall P.R.,
Henault-Brunet V., Maiz Apellaniz J., McEvoy C.M., Sana H., Simon-Diaz S.,
Taylor W.D., Vink J.S.
<Astron. Astrophys., 574, A13-13 (2015)>
=2015A&A...574A..13E 2015A&A...574A..13E
ADC_Keywords: Stars, B-type ; MK spectral classification ; Radial velocities
Keywords: stars: fundamental parameters - stars: early-type -
open clusters and associations: individual: NGC 2060 -
open clusters and associations: individual: NGC 2070 -
open clusters and associations: individual: Hodge 301 -
open clusters and associations: individual: SL 639
Abstract:
We present spectral classifications for 438 B-type stars observed as
part of the VLT-FLAMES Tarantula Survey (VFTS) in the 30 Doradus
region of the Large Magellanic Cloud. Radial velocities are provided
for 307 apparently single stars, and for 99 targets with
radial-velocity variations which are consistent with them being
spectroscopic binaries. We investigate the spatial distribution of the
radial velocities across the 30 Dor region, and use the results to
identify candidate runaway stars. Excluding potential runaways and
members of two older clusters in the survey region (SL639 and
Hodge301), we determine a systemic velocity for 30 Dor of
271.6±12.2km/s from 273 presumed single stars. Employing a 3σ
criterion we identify nine candidate runaway stars (2.9% of the single
stars with radial-velocity estimates). The projected rotational
velocities of the candidate runaways appear to be significantly
different to those of the full B-type sample, with a strong preference
for either large (≥345km/s) or small (≤65km/s) rotational
velocities. Of the candidate runaways, VFTS358 (classified B0.5: V)
has the largest differential radial velocity (-106.9±16.2km/s), and
a preliminary atmospheric analysis finds a significantly enriched
nitrogen abundance of 12+log(N/H)> 8.5. Combined with a large
rotational velocity (vesini=345±22km/s), this is suggestive of
past binary interaction for this star.
Description:
All of the VFTS data discussed here were obtained using the
Medusa-Giraffe mode of the Fibre Large Array Multi-Element
Spectrograph (FLAMES) instrument on the Very Large Telescope (VLT).
The Medusa fibres (which subtend 1.2" on the sky) were used to relay
light from up to 130 targets simultaneously to the Giraffe
spectrograph (see Pasquini et al., 2002Msngr.110....1P 2002Msngr.110....1P).
Full details of the observational strategy and reduction of the data
are given in Paper I (Evans et al., 2011A&A...530A.108E 2011A&A...530A.108E).
In brief, the ESO Common Pipeline Library FLAMES recipes were used to
undertake bias subtraction, fibre location, summed extractions of each
object, division by a normalised flat-field, and wavelength
calibration. Subsequent processing included correction of the spectra
to the heliocentric frame, sky subtraction, and rejection of
significant cosmic rays.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 34 13 Rest wavelengths used to estimate radial
velocities for the narrow- and broad-lined
stars (Sets 1 and 2, respectively)
table7.dat 163 438 Spectral classifications and radial velocities
for B-type stars in the VFTS
tablea1.dat 64 162 Line-by-line radial-velocity estimates for
single stars using the Set 1 absorption lines
tablea2.dat 46 203 Line-by-line radial-velocity estimates for
single stars using the Set 2 absorption lines
tablea3.dat 81 99 Line-by-line radial-velocity estimates for
single-lined binaries using absorption lines
in the LR02 observations
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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+, 2013)
J/A+A/550/A109 : VLT-FLAMES Tarantula Survey: vsini measures (Dufton+ 2013)
J/A+A/564/L7 : VLT-FLAMES Tarantula Survey: VFTS 822 (Kalari+, 2014)
J/A+A/560/A29 : O-stars in VLT-FLAMES Tarantula Survey (Ramirez-Agudelo+ 2013)
J/A+A/564/A39 : VLTS. OVz stars in 30 Dor (Sabin-Sanjulian+, 2014)
J/A+A/564/A40 : VFTS. O-type stellar content of 30 Dor (Walborn+, 2014)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1 I1 --- Set [1/2] Set number
3- 7 A5 --- Ion Ion (HeI, CII or SiIII)
10- 16 F7.2 0.1nm lambda [4000/5000] Wavelength λ, in Å (1)
19- 22 F4.1 km/s DV [-3.5/2.8] Average difference between the
velocity estimates for each line and the
final velocity for each star
24- 27 F4.1 km/s e_DV rms uncertainty on DV
29 A1 --- --- [(]
30- 33 A4 --- n_DV Giraffe setting (LR02 or LR03)
34 A1 --- --- [)]
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Note (1): Wavelengths are taken from the NIST atomic spectra database
(Kramida et al., 2012, http:/physics.nist.gov/asd); the adopted value for CII
is the average of the two stronger transitions.
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- VFTS [1/891] VFTS identifier
5- 22 A18 --- SpType Spectral type
23 A1 --- Mult [X-] Binary status
(from Dunstall et al., in prep.)
25- 28 A4 --- Ha Hα morphology code (1)
30- 34 F5.2 mag Vmag [11.7/17.2]?=- V magnitude (2)
36- 40 F5.2 mag B-V ?=- B-V colour index (2)
42- 46 F5.1 km/s RV [164/333]?=- Estimated radial velocity
48- 51 F4.1 km/s e_RV ?=- Standard deviation of RV
53 A1 --- n_RV [123B] Method/lines used to estimate RV (3)
55- 77 A23 --- AName Alternative identifier(s) used in the literature
79-163 A85 --- Com Previous classifications and other relevant
comments (4)
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Note (1): Hα morphology code as follows:
a = (photospheric) absorption
e = (stellar) emission
f = flat, with no indication of the nature of the line profiles outside
the region of nebular emission (i.e. no strong, broad emission)
q = P-Cygni profile (used classically to distinguish from a "p" suffix,
which simply indicates peculiar)
Note (2): from Paper I, Evans et al., 2011A&A...530A.108E 2011A&A...530A.108E, Cat. J/A+A/530/A108.
Note (3): Method/lines used to estimate RV as follows:
1 = refer to the lines listed in Table 3, Set 1
2 = refer to the lines listed in Table 3, Set 2
3 = indicates the three stars for which other metal lines were used
B = indicates that the estimate is the mean value from the multi-epoch data
available (see Sect. 4.2, with the limitations of these as estimates of
the centre-of-mass velocities discussed in Sect. A.3)
Note (4): Aliases/past classifications are from:
F60 = Feast et al., 1960MNRAS.121..337F 1960MNRAS.121..337F)
AL = Andrews & Lindsay, 1964IrAJ....6..241A 1964IrAJ....6..241A)
Sk = Sanduleak, 1970CoTol..89....1S 1970CoTol..89....1S)
BE74 = Bohannan & Epps, 1974A&AS...18...47B 1974A&AS...18...47B)
BI = Brunet et al., 1975A&AS...21..109B 1975A&AS...21..109B)
W84 = Walborn, 1984, IAU Symp. 108, 243)
Mk = Melnick, 1985A&A...153..235M 1985A&A...153..235M)
W86 = Walborn 1986, IAU Symp. 116, 185)
T88 = Testor et al., 1988Msngr..54...43T 1988Msngr..54...43T)
ST92 = Schild & Testor, 1992A&AS...92..729S 1992A&AS...92..729S)
P93 = Parker, 1993AJ....106..560P 1993AJ....106..560P)
WB97 = Walborn & Blades, 1997ApJS..112..457W 1997ApJS..112..457W)
B99 = Bosch et al., 1999A&AS..137...21B 1999A&AS..137...21B).
The crosschecks with the catalogues from Andrews & Lindsay
(1964IrAJ....6..241A 1964IrAJ....6..241A) and Bohannan & Epps (1974A&AS...18...47B 1974A&AS...18...47B) employed
the updated astrometry from Howarth (2012A&A...548A..16H 2012A&A...548A..16H,
Cat. J/A+A/548/16, 2013A&A...555A.141H 2013A&A...555A.141H, Cat. J/A+A/555/A141).
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- VFTS [1/891] VFTS identifier
5- 9 F5.1 km/s V4121 ?=- HeI λ4121Å line radial velocity
11- 15 F5.1 km/s V4267 ?=- CII λ4267Å line radial velocity
17- 21 F5.1 km/s V4438 ?=- HeI λ4438Å line radial velocity
23- 27 F5.1 km/s V4553-2 ?=- SiIII λ4553Å line radial velocity
(LR02)
29- 33 F5.1 km/s V4553-3 ?=- SiIII λ4553Å line radial velocity
(LR03)
35- 39 F5.1 km/s V4568 ?=- SiIII λ4568Å line radial velocity
41- 45 F5.1 km/s V4575 ?=- SiIII λ4575Å line radial velocity
47- 51 F5.1 km/s V4713 ?=- HeI λ4713Å line radial velocity
53- 57 F5.1 km/s RV Weighted mean velocity for each star
(from Eq.(1), weigths are central depths)
59- 62 F4.1 km/s e_RV Standard deviation for RV (from Eq.(2),
weighted by the central depths)
64 I1 --- o_RV Number of lines used in calculation of
RV and e_RV
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Byte-by-byte Description of file: tablea2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- VFTS [1/891] VFTS identifier
5- 9 F5.1 km/s V4009 ?=- HeI λ4009Å line radial velocity
11- 15 F5.1 km/s V4144 ?=- HeI λ4144Å line radial velocity
17- 21 F5.1 km/s V4388 ?=- HeI λ4388Å line radial velocity
23- 27 F5.1 km/s V4713 ?=- HeI λ4713Å line radial velocity
29- 33 F5.1 km/s V4922 ?=- HeI λ4922Å line radial velocity
35- 39 F5.1 km/s RV Weighted mean velocity for each star
(from Eq.(1), weigths are central depths)
41- 44 F4.1 km/s e_RV Standard deviation for RV (from Eq.(2),
weighted by the central depths)
46 I1 --- o_RV Number of lines used in calculation of
RV and e_RV
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Byte-by-byte Description of file: tablea3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- VFTS [1/891] VFTS identifier
5- 9 I5 d MJD Modified Julian Date of the co-added
observations used for these measurements (1)
11- 15 F5.1 km/s V4009 ?=- HeI λ4009Å line radial velocity
17- 21 F5.1 km/s V4144 ?=- HeI λ4144Å line radial velocity
23- 27 F5.1 km/s V4169 ?=- HeI λ4169Å line radial velocity
29- 33 F5.1 km/s V4267 ?=- CII λ4267Å line radial velocity
35- 39 F5.1 km/s V4388 ?=- HeI λ4388Å line radial velocity
41- 45 F5.1 km/s V4438 ?=- HeI λ4438Å line radial velocity
47- 51 F5.1 km/s V4553 ?=- SiIII λ4553Å line radial velocity
53- 57 F5.1 km/s V1 Weighted mean (single-epoch) velocity for each
star (from Eq. (1), weigths are central depths)
59- 62 F4.1 km/s e_V1 Standard deviation for V1 (from Eq.(2),
weighted by the central depths)
64 I1 --- o_V1 Number of lines used in calculation of
V1 and e_V1
66- 70 F5.1 km/s RV ?=- Estimated mean vr calculated from the
multi-epoch measurements from
Dunstall et al. (in prep.)
72- 75 F4.1 km/s e_RV ? Standard deviation of estimated mean RV
77- 81 F5.1 km/s s_RV ?=- Maximum difference in the radial velocity
estimates between the available epochs
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Note (1): see Appendix of Paper I (Evans et al., 2011A&A...530A.108E 2011A&A...530A.108E)
for details of exposures.
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History:
From electronic version of the journal
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 2013A&A...550A.108V 2013A&A...550A.108V, Cat. J/A+A/550/A108
Dufton et al., Paper X 2013A&A...550A.109D 2013A&A...550A.109D, Cat. J/A+A/550/A109
Doran et al., Paper XI 2013A&A...558A.134D 2013A&A...558A.134D
Ramirez-Agudelo et al., Paper XII 2013A&A...560A..29R 2013A&A...560A..29R, Cat. J/A+A/560/A29
Sabin-Sanjulian et al., Paper XIII 2014A&A...564A..39S 2014A&A...564A..39S, Cat. J/A+A/564/A39
Walborn et al., Paper XIV 2014A&A...564A..40W 2014A&A...564A..40W, Cat. J/A+A/564/A40
Kalari et al., Paper XV 2014A&A...564L...7K 2014A&A...564L...7K, Cat. J/A+A/564/L7
Maiz Apellaniz et al., Paper XVI 2014A&A...564A..63M 2014A&A...564A..63M
Bestenlehner et al., Paper XVII 2014A&A...570A..38B 2014A&A...570A..38B
(End) Patricia Vannier [CDS] 06-Mar-2015