J/A+A/643/A138 Possible runaway stars list (Maiz Apellaniz+, 2020)
The Villafranca catalog of Galactic OB groups. I. Systems with O2-O3.5 stars.
Maiz Apellaniz J., Crespo Bellido P., Barba R.H., Fernandez Aranda R.,
Sota A.
<Astron. Astrophys., 643, A138 (2020)>
=2020A&A...643A.138M 2020A&A...643A.138M (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Associations, stellar ; Stars, OB
Keywords: astrometry - catalogs - Galaxy: structure -
open clusters and associations: general -
stars: kinematics and dynamics - stars: early-type
Abstract:
The spectral classifications of the Galactic O-Star Spectroscopic
Survey (GOSSS) and the astrometric and photometric data from Gaia have
significantly improved our ability to measure distances and determine
memberships of stellar groups (clusters, associations, or parts
thereof) with OB stars. In the near future, the situation will be
further improved thanks to subsequent Gaia data releases and new
photometric and spectroscopic surveys.
We initiated a program to identify and determine the membership of
Galactic stellar groups with OB stars and measure distances to them.
Given the data currently available, we started with the identification
and distance determinations of groups with O stars. In this paper, we
concentrate on groups that contain stars with the earliest spectral
subtypes.
We used GOSSS to select Galactic stellar groups with O2-O3.5 stars and
the method described in paper 0 of this series, which combines Gaia
DR2 G + GBP + GRP photometry, positions, proper motions, and
parallaxes to assign robust memberships and measure distances. We also
included Collinder 419 and NGC 2264, the clusters cited in that paper,
to generate our first list of 16 O-type Galactic stellar groups.
We derived distances, determined the membership, and analyzed the
structure of sixteen Galactic stellar groups with O stars, Villafranca
O-001 to Villafranca O-016, including the fourteen groups with the
earliest-O-type optically accessible stars known in the Milky Way. We
compared our distance with previous results from the literature and
establish that the best consistency is with (the small number of) VLBI
parallaxes and the worst is with kinematic distances.
Our results indicate that very massive stars can form in relatively
low-mass clusters or even in near-isolation, as is the case for the
Bajamar star in the North America nebula. This lends support to the
hierarchical scenario of star formation, where some stars are born in
well-defined bound clusters but others are born in associations that
are unbound from the beginning: groups of newborn stars come in many
shapes and sizes. We propose that HD 64568 and HD 64315 AB could
have been ejected simultaneously from Haffner 18 (Villafranca O-012 S).
Our results are consistent with a difference of ≃20µas in the Gaia
DR2 parallax zero point between bright and faint stars.
Description:
Possible runaways from each group are given in Table A.2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea2.dat 81 60 Possible runaway stars
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
Byte-by-byte Description of file: tablea2.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Group Group ID (O-NNN)
8- 26 I19 --- GaiaDR2 Gaia DR2 ID
28- 50 A23 --- OName Other ID
51 A1 --- n_OName [+] Note on Oname (1)
53- 59 F7.4 mas Plx Gaia DR2 parallax
61- 66 F6.4 mas e_Plx Gaia DR2 parallax error
68- 74 F7.4 mag Gmag Gaia DR2 G magnitude
76- 81 F6.4 mag GBP-GRP Gaia DR2 BP-RP colour index
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Note (1): Note as follows:
+ = Target with bad RUWE
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 27-Jan-2021