J/A+A/621/A115 Vela OB2 members (Cantat-Gaudin+, 2019)
A ring in a shell: the large-scale 6D structure of the Vela OB2 complex.
Cantat-Gaudin T., Mapelli M., Balaguer-Nunez L., Jordi C., Sacco G.,
Vallenari A.
<Astron. Astrophys. 621, A115 (2019)>
=2019A&A...621A.115C 2019A&A...621A.115C (SIMBAD/NED BibCode)
ADC_Keywords: Associations, stellar ; Populations, stellar
Keywords: stars: pre-main sequence - ISM: individual objects: IRAS Vela Shell -
ISM: individual objects: Gum Nebula - ISM: bubbles -
open clusters and associations: individual: Vela OB2
Abstract:
The Vela OB2 association is a group of 10Myr stars exhibiting a
complex spatial and kinematic substructure. The all-sky Gaia DR2
catalogue contains proper motions, parallaxes (a proxy for distance)
and photometry that allow us to separate the various components of
Vela OB2. We characterise the distribution of the Vela OB2 stars on a
large spatial scale, and study its internal kinematics and dynamic
history. We make use of Gaia DR2 astrometry and published Gaia-ESO
Survey data. We apply an unsupervised classification algorithm to
determine groups of stars with common proper motions and parallaxes.
We find that the association is made up of a number of small groups,
with a total current mass over 2330M☉. The three-dimensional
distribution of these young stars trace the edge of the gas and dust
structure known as the IRAS Vela Shell across 180 pc and shows clear
signs of expansion. We propose a common history for Vela OB2 and the
IRAS Vela Shell. The event that caused the expansion of the shell
happened before the Vela OB2 stars formed, imprinted the expansion in
the gas the stars formed from, and most likely triggered star
formation.
Description:
All columns from the Gaia DR2 catalogue, except the membership
probability which was computed with the unsupervised classification
scheme UPMASK applied to the Gaia DR2 proper motions and parallaxes.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
velaypop.dat 444 3527 List of probable members and membership
probabilities
--------------------------------------------------------------------------------
See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
Byte-by-byte Description of file: velaypop.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 F18.14 deg RAdeg Barycentric right ascension (ICRS)
at Ep=2015.5 (ra)
20- 38 F19.15 deg DEdeg Barycentric declination (ICRS)
at Ep=2015.5 (dec)
40- 58 I19 --- Source Unique source identifier (source_id)
60- 77 F18.14 deg GLON Galactic longitude (l)
79- 99 E21.17 deg GLAT Galactic latitude (b)
101-118 F18.16 mas Plx Absolute stellar parallax (parallax)
120-139 F20.18 mas e_Plx Standard error of parallax
(parallax_error)
141-159 F19.16 mas/yr pmRA Proper motion in right ascension
direction (pmRA*cosDE) (pmra)
161-180 F20.18 mas/yr e_pmRA Standard error of proper motion in right
ascension direction (pmra_error)
182-200 F19.16 mas/yr pmDE Proper motion in declination direction
(pmdec)
202-221 F20.18 mas/yr e_pmDE Standard error of proper motion in
declination direction (pmdec_error)
223-235 E13.10 --- RADEcor Correlation between right ascension and
declination (radeccorr)
237-249 E13.10 --- RAPlxcor Correlation between right ascension and
parallax (raparallaxcorr)
251-263 E13.10 --- RApmRAcor Correlation between right ascension and
proper motion in right ascension
(rapmracorr)
265-277 E13.10 --- RApmDEcor Correlation between right ascension and
proper motion in declination
(rapmdeccorr)
279-291 E13.10 --- DEPlxcor Correlation between declination and
parallax (decparallaxcorr)
293-305 E13.10 --- DEpmRAcor Correlation between declination and
proper motion in right ascension
(decpmracorr)
307-319 E13.10 --- DEpmDEcor Correlation between declination and
proper motion in declination
(decpmdeccorr)
321-333 E13.10 --- PlxpmRAcor Correlation between parallax and proper
motion in right ascension
(parallaxpmracorr)
335-347 E13.10 --- PlxpmDEcor Correlation between parallax and proper
motion in declination
(parallaxpmdeccorr)
349-361 E13.10 --- pmRApmDEcor Correlation between proper motion in
right ascension and proper motion in
declination (pmrapmdeccorr)
363-365 I3 --- o_Gmag Number of observations contributing to G
photometry (photgn_obs)
367-376 F10.7 mag Gmag G-band mean magnitude (Vega)
(photgmean_mag)
378-387 F10.7 mag BPmag Integrated BP mean magnitude (Vega)
(photbpmean_mag)
389-398 F10.7 mag RPmag Integrated RP mean magnitude (Vega)
(photrpmean_mag)
400-410 F11.8 mag BP-RP BP-RP colour (bp_rp)
412-425 F14.6 --- chi2AL AL chi-square value
(astrometricchi2al)
427-429 I3 --- NgAL Number of good observations AL
(astrometricngoodobsal)
431-439 F9.7 --- E(BR/RP) BP/RP excess factor
(photbprpexcessfactor)
441-444 F4.2 --- Pmemb Membership probability (proba)
--------------------------------------------------------------------------------
Acknowledgements:
Tristan Cantat-Gaudin, tcantat(at)fqa.ub.edu
(End) Patricia Vannier [CDS] 28-Nov-2018