J/ApJ/878/111 Members in Serpens Molecular Cloud with Gaia DR2 (Herczeg+, 2019)
An initial overview of the extent and structure of recent star formation within
the Serpens Molecular Cloud using Gaia Data Release 2.
Herczeg G.J., Kuhn M.A., Zhou X., Hatchell J., Manara C.F., Johnstone D.,
Dunham M., Bhardwaj A., Jose J., Yuan Z.
<Astrophys. J., 878, 111 (2019)>
=2019ApJ...878..111H 2019ApJ...878..111H
ADC_Keywords: Clusters, open; Proper motions; Parallaxes, trigonometric;
Photometry; Optical
Keywords: open clusters and associations: general ; planetary systems ;
protoplanetary disks ; stars: low-mass ; stars: pre-main sequence
Abstract:
The dense clusters within the Serpens Molecular Cloud are among the
most active regions of nearby star formation. In this paper, we use
Gaia DR2 parallaxes and proper motions to statistically measure
∼1167 kinematic members of Serpens, few of which have been previously
identified, to evaluate the star formation history of the complex. The
optical members of Serpens are concentrated in three distinct groups
located at 380-480pc; the densest clusters are still highly obscured
by optically thick dust and have few optical members. The total
population of young stars and protostars in Serpens is at least
2000 stars, including past surveys that were most sensitive to
protostars and disks, and may be much higher. Distances to dark clouds
measured from deficits in star counts are consistent with the
distances to the optical star clusters. The Serpens Molecular Cloud is
seen in the foreground of the Aquila Rift, dark clouds located at
600-700pc, and behind patchy extinction, here called the Serpens
Cirrus, located at ∼250pc. Based on the lack of a distributed
population of older stars, the star formation rate throughout the
Serpens Molecular Cloud increased by at least a factor of 20 within
the past ∼5Myr. The optically bright stars in Serpens Northeast are
visible because their natal molecular cloud has been eroded, not
because they were flung outwards from a central factory of star
formation. The separation between subclusters of 20-100pc and the
absence of an older population together lead to speculation that an
external forcing was needed to trigger the active star formation.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table7.dat 110 3813 High-probability candidate members of the
Serpens Star-forming Region
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See also:
B/ocl : Optically visible open clusters and Candidates (Dias+ 2002-2015)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
VIII/64 : Westerhout's Catalogue of 82 Discrete Sources (Westerhout 1958)
VII/20 : Catalogue of HII Regions (Sharpless 1959)
VII/7 : Lynds' Catalogue of Dark Nebulae (LDN) (Lynds 1962)
J/AJ/117/354 : OB associations from Hipparcos (de Zeeuw+, 1999)
J/AJ/130/188 : Young stars in Trumpler 37 & NGC 7160 (Sicilia-Aguilar+, 2005)
J/A+A/450/147 : IzJHKs photometry of Collinder 359 (Lodieu+, 2006)
J/A+A/463/275 : Chandra obs. of Serpens star-forming region (Giardino+, 2007)
J/ApJ/686/1195 : IR photometry in the γ Vel cluster (Hernandez+, 2008)
J/ApJ/688/377 : Low-mass objects in Upper Scorpius. II. (Slesnick+, 2008)
J/A+A/519/A27 : CO maps in Serpens (Duarte-Cabral+, 2010)
J/ApJ/725/2485 : X-rays from the star-forming complex W40 (Kuhn+, 2010)
J/AJ/140/266 : NGC 1333 X-ray luminous YSOs properties (Winston+, 2010)
J/PASJ/63/S1 : Atlas & catalog of dark clouds based on 2MASS (Dobashi+, 2011)
J/ApJS/209/29 : MYStIX: Mid-IR observations and catalogs (Kuhn+, 2013)
J/ApJ/779/113 : IR photometry of YSOs in the W40 region (Mallick+, 2013)
J/ApJS/209/31 : The MYStIX IR-Excess Source catalog (MIRES) (Povich+, 2013)
J/ApJ/787/109 : Age estimates for NGC 2024 and ONC stars (Getman+, 2014)
J/ApJ/787/107 : Spatial structure of young stellar clusters. I. (Kuhn+, 2014)
J/ApJS/213/1 : The MSFRs Omnibus X-ray Catalog (MOXC) (Townsley+, 2014)
J/ApJS/220/11 : SEDs of Spitzer YSOs in the Gould Belt (Dunham+, 2015)
J/AJ/149/103 : Spectroscopy of candidate YSOs in Serpens (Erickson+, 2015)
J/ApJ/806/231 : MISFITS survey: HCO+ obs. of Spitzer YSOs (Heiderman+, 2015)
J/A+A/584/A91 : Cat. of dense cores in Aquila from Herschel (Konyves+, 2015)
J/MNRAS/448/1551 : JCMT Gould Belt Survey: Serpens MWC 297 (Rumble+, 2015)
J/ApJ/822/49 : Cand. YSOs in AFGL 333 with NEWFIRM & Spitzer (Jose+, 2016)
J/MNRAS/461/4022 : JCMT Gould Belt Survey: Southern Orion A (Mairs+, 2016)
J/ApJS/229/28 : SFiNCs: X-ray, IR and membership catalogs (Getman+, 2017)
J/A+A/618/A93 : Gaia DR2 open clusters in the Milky Way (Cantat-Gaudin+, 2018)
J/ApJ/867/151 : YSOs in Gould Belt regions with Gaia-DR2 data (Dzib+, 2018)
J/AJ/156/84 : APOGEE-2 survey of Orion Complex. II. (Kounkel+, 2018)
J/AJ/156/271 : The stellar membership of the Taurus SFR (Luhman, 2018)
J/A+A/610/A64 : Distance to the clouds in Chamaeleon complex (Voirin+, 2018)
J/AJ/155/241 : Chandra X-ray obs. of YSOs in Serpens South (Winston+, 2018)
J/A+A/620/A172 : Solar neighbourhood young stars 3D mapping (Zari+, 2018)
J/A+A/626/A17 : Young population in Vela-Puppis region (Cantat-Gaudin+, 2019)
J/A+A/623/A112 : The Sco OB2 population from Gaia DR2 data (Damiani+, 2019)
J/ApJ/870/32 : Kinematics in young star clusters & associations (Kuhn+, 2019)
Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- Gaia Gaia DR2 identifier (1)
21- 29 F9.5 deg RAdeg [272/290.6] Right Ascension (ICRS)
at Ep=2015.5 (1)
31- 38 F8.5 deg DEdeg [-8/11.4] Declination (ICRS) at Ep=2015.5 (1)
40- 45 F6.3 mas/yr pmRA [-0.52/5.48] Proper motion in right ascension
direction (pmRA*cosDE) (1)
47- 53 F7.3 mas/yr pmDE [-11.4/-5.3] Proper motion in declination
direction (1)
55- 59 F5.3 mas Plx [1.8/3.2] Parallax (1)
61- 65 F5.3 mas e_Plx [0.02/0.6] Uncertainty in Plx (1)
67- 72 F6.3 mag Gmag [5.3/19] G-band mean magnitude (1)
74- 79 F6.3 mag Bpmag [6.2/21.8]? Integrated BP mean magnitude (1)
81- 86 F6.3 mag Rpmag [4.5/18]? Integrated RP mean magnitude (1)
88- 91 F4.2 mas epsi [0/2] Excess astrometric noise of the source (1)
93- 96 F4.2 deg N7 [0.04/1.3] 7th nearest spatial neighbor
98-101 F4.2 mas/yr NPM7 [0.07/3.34] 7th nearest proper motion neighbor
103-110 A8 --- Reg Region (2)
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Note (1): These values come from the Gaia DR2 catalog (I/345).
Note (2): Region values include --
'N/A' = non-members;
Distrib = likely members of the distributed Serpens star-formation.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 04-Dec-2020