J/MNRAS/522/3124 OB stars and associations in Auriga (Quintana+, 2023)
Mapping the distribution of OB stars and associations in Auriga.
Quintana A.L., Wright N.J., Jeffries R.D.
<Mon. Not. R. Astron. Soc., 522, 3124-3137 (2023)>
=2023MNRAS.522.3124Q 2023MNRAS.522.3124Q (SIMBAD/NED BibCode)
ADC_Keywords: Associations, stellar ; Stars, OB ; Parallaxes, trigonometric ;
Positional data ; Proper motions ; Stars, ages ;
Stars, distances ; Stellar distribution
Keywords: stars: distances - stars: early-type -
stars: kinematics and dynamics - stars: massive; Galaxy: structure -
open clusters and associations: individual: Aur OB1, Aur OB2,
Alicante 11, Alicante 12, COIN-Gaia_16, Gulliver 8, Kronberger 1,
NGC 1778, NGC 1893, NGC 1912, NGC 1960, Stock 8
Abstract:
OB associations are important probes of recent star formation and
Galactic structure. In this study, we focus on the Auriga
constellation, an important region of star formation due to its
numerous young stars, star-forming regions, and open clusters. We show
using Gaia data that its two previously documented OB associations,
Aur OB1 and OB2, are too extended in proper motion and distance to be
genuine associations, encouraging us to revisit the census of OB
associations in Auriga with modern techniques. We identify 5617
candidate OB stars across the region using photometry, astrometry and
our SED fitting code, grouping these into five high-confidence OB
associations using HDBSCAN. Three of these are replacements to the
historical pair of associations - Aur OB2 is divided between a
foreground and a background association - while the other two
associations are completely new. We connect these OB associations to
the surrounding open clusters and star-forming regions, analyse them
physically and kinematically, constraining their ages through a
combination of 3D kinematic traceback, the position of their members
in the HR diagram and their connection to clusters of known age. Four
of these OB associations are expanding, with kinematic ages up to a
few tens of Myr. Finally, we identify an age gradient in the region
spanning several associations that coincides with the motion of the
Perseus spiral arm over the last ∼20Myr across the field of view.
Description:
Position, astrometry and SED-fitted parameters of the 5617 identified
OB stars. Association membership (from 1 to 5) has also been indicated
whenever relevant.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
aur.dat 197 5617 Daya for the 5617 identified OB stars
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See also:
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
Byte-by-byte Description of file: aur.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- GaiaEDR3 Gaia EDR3 source identification number
21- 29 F9.6 deg RAdeg Barycentric right ascension of the source
(ICRS) at Ep=2016.0 (ra)
31- 39 F9.6 deg DEdeg Barycentric right ascension of the source
(ICRS) at Ep=2016.0 (dec)
41- 45 F5.3 mas Plx Absolute stellar parallax of the source at
the Ep=2016.0
47- 51 F5.3 mas e_Plx Standard error of the stellar parallax
at Ep=2016.0
53- 59 F7.3 mas/yr pmRA Proper motion in right ascension pmRA*cosDE
of the source in ICRS at Ep=2016.0
61- 65 F5.3 mas/yr e_pmRA Standard error of proper motion in
right ascension direction
67- 73 F7.3 mas/yr pmDE Proper motion in declination direction of
the source in ICRS at Ep=2016.0
75- 79 F5.3 mas/yr e_pmDE Standard error of proper motion in
declination direction
81- 87 F7.3 mas/yr pml Proper motion in Galactic longitude
direction at Ep=2016.0
89- 93 F5.3 mas/yr e_pml Standard error of proper motion in
Galactic longitude direction
95-101 F7.3 mas/yr pmb Proper motion in Galactic latitude direction
at Ep=2016.0
103-108 F6.3 mas/yr e_pmb Standard error of proper motion in
Galactic latitude direction
110-114 F5.3 [K] logTeffMed Median logarithm of the SED-fitted
effective temperature
116-120 F5.3 [K] logTeffP16 16th percentile logarithm of the SED-fitted
effective temperature from the
posterior distribution
122-126 F5.3 [K] logTeffP84 84th percentile logarithm of the SED-fitted
effective temperature from the
posterior distribution
128-132 F5.3 [Lsun] logLumMed Median logarithm of the SED-fitted
luminosity
134-138 F5.3 [Lsun] logLumP16 16th percentile logarithm of the SED-fitted
luminosity from the posterior distribution
140-144 F5.3 [Lsun] logLumP84 84th percentile logarithm of the SED-fitted
luminosity from the posterior distribution
146-150 F5.3 [Msun] logMassMed Median logarithm of the SED-fitted mass
152-156 F5.3 [Msun] logMassP16 16th percentile logarithm of the SED-fitted
mass from the posterior distribution
158-162 F5.3 [Msun] logMassP84 84th percentile logarithm of the SED-fitted
mass from the posterior distribution
164-168 F5.3 mag AVMed Median extinction in the V-band
170-174 F5.3 mag AVP16 16th percentile of the extinction in the
V-band
176-180 F5.3 mag AVP84 84th percentile of the extinction in the
V-band
182-185 I4 pc DistMed Median SED-fitted distance
187-190 I4 pc DistP16 16th percentile SED-fitted distance from
the posterior distribution
192-195 I4 pc DistP84 84th percentile SED-fitted distance from
the posterior distribution
197 A1 --- Assoc [12345n] Association assigned to each star
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Acknowledgements:
Alexis L. Quintana, a.l.p.quintana(at)keele.ac.uk
(End) Patricia Vannier [CDS] 31-May-2023