J/A+A/665/A108 Gaia-ESO survey. NGC 3293 star abundances (Morel+, 2022)
The Gaia-ESO survey: A spectroscopic study of the young open cluster NGC 3293.
Morel T., Blazere A., Semaan T., Gosset E., Zorec J., Fremat Y., Blomme R.,
Daflon S., Lobel A., Nieva M.F., Przybilla N., Gebran M., Herrero A.,
Mahy L., Santos W., Tautvaisiene G., Gilmore G., Randich S., Alfaro E.J.,
Bergemann M., Carraro G., Damiani F., Franciosini E., Morbidelli L.,
Pancino E., Worley C.C., Zaggia S.
<Astron. Astrophys. 665, A108 (2022)>
=2022A&A...665A.108M 2022A&A...665A.108M (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Stars, fundamental ; Abundances ; Optical
Keywords: open clusters and associations: individual: NGC 3293 -
stars: fundamental parameters - stars: abundances
Abstract:
We present a spectroscopic analysis of the GIRAFFE and UVES data
collected by the Gaia-ESO survey for the young open cluster NGC 3293.
Archive spectra from the same instruments obtained in the framework of
the 'VLT-FLAMES survey of massive stars' are also analysed.
Atmospheric parameters, non-local thermodynamic equilibrium (LTE)
chemical abundances for six elements (He, C, N, Ne, Mg, and Si), or
variability information are reported for a total of about 160 B stars
spanning a wide range in terms of spectral types (B1 to B9.5) and
rotation rate (up to 350km/s). Our analysis leads to about a five-fold
increase in the number of cluster members with an abundance
determination and it characterises the late B-star population in
detail for the first time. We take advantage of the multi-epoch
observations on various timescales and a temporal baseline, sometimes
spanning ∼15 years, to detect several binary systems or intrinsically
line-profile variables. A deconvolution algorithm is used to infer the
current, true (deprojected) rotational velocity distribution. We find
a broad, Gaussian-like distribution peaking around 200-250km/s.
Although some stars populate the high-velocity tail, most stars in the
cluster appear to rotate far from critical. We discuss the chemical
properties of the cluster, including the low occurrence of abundance
peculiarities in the late B stars and the paucity of objects showing
CN-cycle burning products at their surface. We argue that the former
result can largely be explained by the inhibition of diffusion effects
because of fast rotation, while the latter is generally in accord with
the predictions of single-star evolutionary models under the
assumption of a wide range of initial spin rates at the onset of
main-sequence evolution. However, we find some evidence for a less
efficient mixing in two quite rapidly rotating stars that are among
the most massive objects in our sample. Finally, we obtain a cluster
age of ∼20Myrs through a detailed, star-to-star correction of our
results for the effect of stellar rotation (e.g. gravity darkening).
This is significantly older than previous estimates from turn-off
fitting that fully relied on classical, non-rotating isochrones.
Description:
The results are based on GIRAFFE and UVES spectra obtained with the
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 84 192 Summary of observations and sampling properties
table4.dat 417 192 Final apparent parameters and abundances
table5.dat 296 137 Colour excesses and stellar parameters
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See also:
J/A+A/402/549 : UBVRIHalpha photometry of NGC 3293 (Baume+, 2003)
J/A+A/437/467 : VLT-FLAMES survey of massive stars (Evans+, 2005)
J/A+A/457/265 : The VLT-FLAMES Survey of Massive Stars (Dufton+, 2006)
J/A+A/462/591 : CCD Δa-photometry of 8 open clusters (Netopil+, 2007)
J/A+A/605/A85 : NGC 3293 Chandra X-ray observation (Preibisch+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- GES Gaia-ESO ID (HHMMSSss+DDMMSSs)
18- 46 A29 --- Name Main SIMBAD ID
48- 55 A8 --- FS VLT-FLAMES survey of massive stars ID
(NNNN-NNN)
57 I1 --- NbHR03FS Number of epochs FS HR03
59 I1 --- NbHR03GES Number of epochs GES HR03
61 I1 --- NbHR04FS Number of epochs FS HR04
63 I1 --- NbHR04GES Number of epochs GES HR04
65 I1 --- NbHR05FS Number of epochs FS HR05
67 I1 --- NbHR05GES Number of epochs GES HR05
69 I1 --- NbHR06FS Number of epochs FS HR06
71 I1 --- NbHR06GES Number of epochs GES HR06
73 I1 --- NbU520FS Number of epochs FS U520
75 I1 --- NbU520GES Number of epochs GES U520
77 I1 --- Nb Total number of epochs
79- 84 F6.1 d DeltaT Total time span
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- GES Gaia-ESO ID
19- 47 A29 --- Name Main SIMBAD ID
49- 56 A8 --- FS VLT-FLAMES survey of massive stars ID
59- 60 A2 --- fMember [Y N ?] Membership flag
65- 69 I5 K Teff ?=9999 Effective temperature
73- 76 I4 K e_Teff ?=999 Uncertainty effective temperature
80- 83 I4 --- f_Teff ?=0000 Flag effective temperature (1)
89- 92 F4.2 [cm/s2] logg ?=9.99 Surface gravity
98-101 F4.2 [cm/s2] e_logg ?=9.99 Uncertainty surface gravity
104-107 I4 --- f_logg ?=0000 Flag surface gravity (1)
111-114 I4 km/s vsini ?=9999 Projected rotational velocity
119-121 I3 km/s e_vsini ?=999 Uncertainty projected rotational
velocity
125-128 I4 --- f_vsini ?=0000 Flag projected rotational
velocity (1)
132-137 F6.2 km/s RV ?=9.99 Mean radial velocity
139-144 F6.2 km/s s_RV ?=9.99 Dispersion radial velocities
146-151 F6.2 km/s e_RV ?=9.99 Uncertainty mean radial velocity
157-161 F5.3 --- HE1 ?=9.999 Helium abundance
167-171 F5.3 --- e_HE1 ?=9.999 Uncertainty helium abundance
174-177 I4 --- f_HE1 ?=0000 Flag helium abundance (1)
181-185 F5.2 --- loge(CII) ?=99.99 Carbon abundance
190-193 F4.2 --- e_loge(CII) ?=9.99 Uncertainty carbon abundance
196-199 I4 --- f_loge(CII) ?=0000 Flag carbon abundance (1)
203-207 F5.2 --- loge(NII) ?=99.99 Nitrogen abundance
212-215 F4.2 --- e_loge(NII) ?=9.99 Uncertainty nitrogen abundance
218-221 I4 --- f_loge(NII) ?=0000 Flag nitrogen abundance (1)
225-229 F5.2 --- loge(NeI) ?=99.99 Neon abundance
234-237 F4.2 --- e_loge(NeI) ?=9.99 Uncertainty neon abundance
240-243 I4 --- f_loge(NeI) ?=0000 Flag neon abundance (1)
247-251 F5.2 --- loge(MgII) ?=99.99 Magnesium abundance
256-259 F4.2 --- e_loge(MgII) ?=9.99 Uncertainty magnesium abundance
262-265 I4 --- f_loge(MgII) ?=0000 Flag magnesium abundance (1)
269-273 F5.2 --- loge(SiII) ?=99.99 Silicon abundance from SiII lines
278-281 F4.2 --- e_loge(SiII) ?=9.99 Uncertainty silicon abundance
from SiII lines
284-287 I4 --- f_loge(SiII) ?=0000 Flag silicon abundance
from SiII lines (1)
291-295 F5.2 --- loge(SiIII) ?=99.99 Silicon abundance from SiIII lines
300-303 F4.2 --- e_loge(SiIII) ?=9.99 Uncertainty silicon abundance
from SiIII lines
306-309 I4 --- f_loge(SiIII) ?=0000 Flag silicon abundance
from SiIII lines (1)
313-317 F5.2 --- [N/C] ?=99.99 Nitrogen over carbon abundance
ratio
322-325 F4.2 --- e_[N/C] ?=9.99 Uncertainty nitrogen over carbon
abundance ratio
328-331 I4 --- f_[N/C] ?=0000 Flag nitrogen over carbon abundance
ratio (1)
334-366 A33 --- fGES-TECH Gaia-ESO technical flag (2)
368-417 A50 --- fGES-PECULI Gaia-ESO stellar peculiarity flag (2)
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Note (1): Indicates the origin of the determination:
the first, second, third, and fourth digit indicates whether the value is
based on GES GIRAFFE, FS GIRAFFE, GES UVES, or FS UVES, respectively.
For instance, '1001' means that the determination is based on GES GIRAFFE
and FS UVES spectra.
Note (2): See description in Table 2:
Table 2. Flags specific to the WG13 Liege node
-------------------------------------------------------------------------
Flag Results reported? Description
-------------------------------------------------------------------------
Technical
10050-13-16-00 No Insuffcient S/N (≲30)
10106-13-16-01 Yes/No (a) Picket-fence pattern (only UVES)
10302-13-16-01 No Too poor fit of spectrum
10303-13-16-01 No Teff below lowest bound of grid (10kK)
Stellar peculiarity
20010-13-16-00 Yes RV variations: SB1 binary motion
20020-13-16-00 Yes/No (b) SBn, n≥2
21100-13-16-00 Yes/No (b) LPVs: intrinsic variability (c)
25000-13-16-01 Yes/No (b) Intrinsic emission in Balmer lines (d)
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Notes. A suffix indicating the confidence level is added to each flag:
A = probable, B = possible, C = tentative
(Van der Swaelmen et al., 2018, in SF2A-2018: Proceedings of the Annual
meeting of the French Society of Astronomy and Astrophysics, ed.
P. Di Matteo, F. Billebaud, F. Herpin, N. Lagarde, J.B. Marquette,
A. Robin, & O. Venot, 351-353).
(a) = Depends whether all the exposures are affected by this problem.
(b) = See Sect. 3.2 for the criteria for further analysis.
(c) = Either due to pulsations or rotational modulation.
(d) = Double peaked or shell-like
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- GES Gaia-ESO ID
20- 24 F5.3 mag E(B-V) B-V colour excess
28- 32 F5.3 mag e_E(B-V) Uncertainty colour excess
36- 40 I5 K Teffpnrc pnrc effective temperature
42- 45 I4 K e_Teffpnrc Uncertainty pnrc effective temperature
49- 53 F5.3 [cm/s2] loggpnrc pnrc surface gravity
56- 60 F5.3 [cm/s2] e_loggpnrc Uncertainty pnrc surface gravity
64- 68 F5.3 [Lsun] logLpnrc pnrc luminosity
71- 75 F5.3 [Lsun] e_logLpnrc Uncertainty pnrc luminosity
79- 81 I3 km/s vsinipnrc pnrc projected rotational velocity
83- 84 I2 km/s e_vsinipnrc Uncertainty pnrc projected rotational
velocity
88- 91 F4.1 Msun Mpnrc pnrc mass
94- 97 F4.1 Msun e_Mpnrc Uncertainty pnrc mass
100-102 I3 km/s Vcpnrc pnrc critical velocity
104-105 I2 km/s e_Vcpnrc Uncertainty pnrc critical velocity
108-109 I2 deg ipnrc pnrc inclination angle
111-112 I2 deg e_ipnrc Uncertainty pnrc inclination angle
116-120 F5.3 --- V/Vcpnrc pnrc V over Vc
123-127 F5.3 --- e_V/Vcpnrc Uncertainty pnrc V over Vc
131-135 F5.3 --- omegapnrc pnrc omega (ratio of the current to the
critical surface angular velocity)
138-142 F5.3 --- e_omegapnrc Uncertainty pnrc omega
147-151 F5.3 --- ttMSpnrc pnrc fraction of main-sequence lifetime
156-160 F5.3 --- e_ttMSpnrc Uncertainty pnrc fraction of
main-sequence lifetime
164-169 F6.4 [yr] logtpnrc pnrc age
173-178 F6.4 [yr] e_logtpnrc Uncertainty pnrc age
182-187 F6.4 [K] logTeffavg Average effective temperature
191-196 F6.4 [K] e_logTeffavg Uncertainty average effective temperature
200-205 F6.4 [cm/s2] loggavg Average surface gravity
209-214 F6.4 [cm/s2] e_loggavg Uncertainty average surface gravity
217-222 F6.4 [Lsun] logLavg Average luminosity
226-231 F6.4 [Lsun] e_logLavg Uncertainty average luminosity
236-240 I5 K Teffapp Apparent effective temperature
242-245 I4 K e_Teffapp Uncertainty apparent effective temperature
249-253 F5.3 [Lsun] logLapp Apparent luminosity
256-260 F5.3 [Lsun] e_logLapp Uncertainty apparent luminosity
264-269 F6.4 --- ttMSapp Apparent fraction of main-sequence lifetime
273-278 F6.4 --- e_ttMSapp Uncertainty apparent fraction of
main-sequence lifetime
282-287 F6.4 [yr] logtapp Apparent age
291-296 F6.4 [yr] e_logtapp Uncertainty apparent age
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Acknowledgements:
Thierry Morel, tmorel(at)uliege.be
(End) Patricia Vannier [CDS] 28-Jul-2022