J/AJ/168/25 Spectral types of OB stars <200Myr from Gaia DR3 (Ge+, 2024)
Evolution of the local spiral structure revealed by OB-type stars in Gaia DR3.
Ge Q.A., Li J.J., Hao C.J., Lin Z.H., Hou L.G., Liu D.J., Li Y.J.,
Bian S.B.
<Astron. J., 168, 25 (2024)>
=2024AJ....168...25G 2024AJ....168...25G
ADC_Keywords: Stars, OB; Effective temperatures; Spectral types;
Parallaxes, trigonometric; Surveys; Milky Way
Keywords: Galaxy structure ; Galaxy evolution ; Galaxy stellar content ;
Solar neighborhood
Abstract:
The structure and evolution of the spiral arms of the Milky Way have
long been an important yet controversial issue. The wide age range of
OB-type stars, coupled with the large amount of high-precision
astrometric data provided by Gaia DR3, presents us with an opportunity
to explore this issue. After constructing overdensity maps and
examining the variations of overdensities with Galactocentric distance
along the Galactic azimuth, we compare the spiral structures traced by
B3-B5, B6-B7, B8, and B9 stars with those of young O-B2 stars in the
vicinity of the Sun. We find that as the ages of the OB tracer stars
increase, the Perseus Arm traced by them gradually shifts toward the
anti-Galactic center direction, and the pitch angle of the Carina Arm
gradually decreases. These results will help us to understand better
the evolutionary properties of nearby spiral arms.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 83 404171 Parallaxes and Teff of OB stars in Gaia DR3
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See also:
B/pastel : The PASTEL catalogue (Soubiran+, 2016-)
B/mk : Catalogue of Stellar Spectral Classifications (Skiff, 2009- )
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
J/ApJS/208/9 : Intrinsic colors & temperatures of PMS stars (Pecaut+, 2013)
J/ApJ/885/131 : High-mass SFR plx & proper motion with VLBI (Reid+, 2019)
J/A+A/643/A138 : Possible runaway stars list (Maiz Apellaniz+, 2020)
J/A+A/652/A102 : 3794 open clusters parameters (Hao+, 2021)
J/MNRAS/504/2968 : The Alma catalogue of OB stars - II. (Pantaleoni+, 2021)
J/A+A/651/A104 : Spiral arms Gaia EDR3 (Poggio+, 2021)
J/A+A/645/L8 : Plxs & proper motions of OB stars from Gaia EDR3 (Xu+, 2021)
J/A+A/657/A131 : Ten new systems with O stars (Maiz Apellaniz+, 2022)
J/A+A/662/A66 : Hot stars from LAMOST DR6 (Xiang+, 2022)
J/A+A/678/A111 : Milky Way through A stars (Ardevol+, 2023)
J/A+A/674/A39 : Gaia DR3. 95 extrasolar planets (Gaia Coll.+, 2023)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- GaiaDR3 Unique source identifier with Gaia DR3
21- 28 F8.4 deg RAdeg Gaia DR3 right ascension (ICRS) at Epoch=2016
30- 37 F8.4 deg DEdeg Gaia DR3 declination (ICRS) at Epoch=2016
39- 44 F6.3 mas Plx [0.06/38.1] Absolute stellar parallax
46- 50 F5.3 mas e_Plx [0.008/1] Standard error on Plx
52- 56 I5 K Teff [10000/54889]?=-9999 Effective temperature
derived by ESP-HS module (1)
58- 83 A26 --- SpT Spectral type based on Teff or from the Skiff
catalog (B/mk) if no Teff
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Note (1): We adopted Gaia DR3 teff_esphs, derived by fitting the GBP/GRP
spectrophotometry (and Gaia Radial Velocity Spectrometer spectra if
available), without parallaxes, using the Extended Stellar
Parametrizer for Hot Stars (ESP-HS) module, to assign spectral classes
to the stars in our sample.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 03-Sep-2024