J/ApJ/904/196 Stellar parameters of a Young Stellar Snake (Tian, 2020)
Discovery of a Young Stellar Snake with Two Dissolving Cores in the Solar
Neighborhood.
Tian H.-J.
<Astrophys. J., 904, 196 (2020)>
=2020ApJ...904..196T 2020ApJ...904..196T
ADC_Keywords: Clusters, open; Stars, OB; YSOs; Stars, pre-main sequence;
Photometry, G band; Radial velocities; Proper motions
Keywords: Stellar kinematics ; Stellar associations ; Stellar dynamics ;
Open star clusters ; Gould Belt ; OB associations ; Young
stellar objects ; Pre-main sequence stars ; Solar neighborhood ;
Proper motions ; Tidal tails ; Filamentary nebulae
Abstract:
We report the discovery of a young (only 30-40Myr) snake-like
structure (dubbed a stellar snake) in the solar neighborhood from Gaia
DR2. The average distance of this structure is about 310pc from us.
Both the length and width are over 200pc, but the thickness is only
about 80pc. The snake has one tail and two dissolving cores, which can
be clearly distinguished in the 6D phase space. The whole structure
includes thousands of members with a total mass of larger than
2000M☉ in a uniform population. The population is so young that it
cannot be well explained with the classical theory of tidal tails. We
therefore suspect that the snake is hierarchically primordial, rather
than the result of dynamically tidal stripping, even if the snake is
probably expanding. The coherent 5D phase information and the ages
suggest that the snake was probably born in the same environment as
the filamentary structure of Beccari et al. If so, the snake could
extend the sky region of the Vela OB2 association by a factor of ∼2
and supplement the census of its coeval structures. This finding is
useful to understanding the history of the formation and evolution of
the Vela OB2 complex. The age of the snake well matches with that of
the Gould Belt. In the sky region of our interest, we detect one new
open cluster, which is named Tian 1 in this work.
Description:
In this study, we mainly use the astrometric and photometric data from
Gaia DR2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 129 1989 Stellar parameters of candidate members
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/AJ/117/354 : OB associations from Hipparcos (de Zeeuw+, 1999)
J/MNRAS/358/13 : Faint dwarfs in NGC 2547 (Jeffries+, 2005)
J/ApJ/661/1119 : Spectroscopy in the 25 Ori group (Briceno+, 2007)
J/MNRAS/393/538 : Stellar association around gamma Vel (Jeffries+, 2009)
J/A+A/495/807 : Shape parameters for 650 open clusters (Kharchenko+, 2009)
J/A+A/558/A53 : Milky Way global survey star clusters. II. (Kharchenko+, 2013)
J/A+A/563/A94 : Kinematics of the Gamma Vel cluster (Jeffries+, 2014)
J/A+A/561/A142 : Galactic extinction from SDSS BHB stars (Tian+, 2014)
J/A+A/618/A93 : Gaia DR2 open clusters in the Milky Way (Cantat-Gaudin+, 2018)
J/A+A/626/A17 : Young population in Vela-Puppis region (Cantat-Gaudin+, 2019)
J/A+A/621/A115 : Vela OB2 members (Cantat-Gaudin+, 2019)
J/A+A/631/A166 : Members of 5 cluster in Ori OB1a association (Kos+, 2019)
J/AJ/158/122 : Local structure & star formation history of MW (Kounkel+, 2019)
J/ApJ/870/32 : Kinematics in young star clusters & associations (Kuhn+, 2019)
J/ApJS/245/32 : Newly identified star clusters in Gaia DR2 (Liu+, 2019)
J/A+A/621/L3 : Hyades tidal tails with Gaia DR2 (Meingast+, 2019)
J/A+A/621/L2 : Hyades tidal tails revealed by Gaia DR2 (Roeser+, 2019)
J/A+A/633/A99 : Gaia DR2 open clusters in Milky Way. II (Cantat-Gaudin+, 2020)
J/AJ/159/105 : 2 new stellar associations in vicinity of the Sun (Liu+, 2020)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- Gaia Gaia DR2 identifier
21- 30 F10.6 deg GLON [177/223] Galactic longitude, Gaia DR2,
(J2015.5)
32- 41 F10.6 deg GLAT [-13.5/1.84] Galactic latitude, Gaia DR2,
(J2015.5)
43- 47 F5.2 mas/yr pmGLON [-4.29/0.69] Proper motion in GLON
49- 52 F4.2 mas/yr e_pmGLON [0.03/0.8] Uncertainty in pmGLON
54- 58 F5.2 mas/yr pmGLAT [-4.42/1.27] Proper motion in GLAT
60- 63 F4.2 mas/yr e_pmGLAT [0.03/0.7] Uncertainty in pmGLAT
65- 70 F6.2 pc Dist [200/409] Gaia DR2 distance, 1000/plx
72- 76 F5.2 pc e_Dist [0.9/38] Uncertainty in Dist
78- 83 F6.2 km/s RVel [-40.4/99.3]? Radial Velocity from Gaia,
LAMOST, APOGEE
85- 89 F5.2 km/s e_RVel [0.02/23]? Uncertainty in RV
91- 98 F8.2 [-] Fe/H [-0.51/0.23]? Metallicity from LAMOST & APOGEE
100-107 F8.2 [-] e_Fe/H [0.01/0.3]? Uncertainty in Fe/H
109-112 F4.2 [cm/s2] logg [3.9/4.72]? log Surface gravity from LAMOST,
APOGEE
114-117 F4.2 [cm/s2] e_logg [0.01/0.5]? Uncertainty in logg
119-123 F5.2 mag Gmag [0.99/11.9] Gaia Gmag
125-129 F5.2 mag BR-BP [-0.05/3.5] Gaia BR-BP color
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 23-Mar-2022