J/ApJ/727/64 Young stellar groups and their most massive stars (Kirk+, 2011)
Young stellar groups and their most massive stars.
Kirk H., Myers P.C.
<Astrophys. J., 727, 64 (2011)>
=2011ApJ...727...64K 2011ApJ...727...64K
ADC_Keywords: Stars, masses ; YSOs ; Spectral types ; Molecular clouds ;
Associations, stellar
Keywords: ISM: clouds - stars: formation
Abstract:
We analyze the masses and spatial distributions of 14 young stellar
groups in Taurus, Lupus3, ChaI, and IC348. These nearby groups, which
typically contain 20-40 members, have membership catalogs complete to
∼0.02M☉, and are sufficiently young that their locations should
be similar to where they formed. These groups show five properties
seen in clusters having many more stars and much greater surface
density of stars: (1) a broad range of masses, (2) a concentration of
the most massive star toward the center of the group, (3) an
association of the most massive star with a high surface density of
lower mass stars, (4) a correlation of the mass of the most massive
star with the total mass of the group, and (5) the distribution of a
large fraction of the mass in a small fraction of the stars.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 76 352 YSO catalog for Taurus (from Luhman et al.
2010ApJS..186..111L 2010ApJS..186..111L; see Appendix A.1.)
table4.dat 76 237 *YSO catalog for ChaI (mainly from Luhman et al.
2007, Cat. J/ApJS/173/104)
table5.dat 49 70 YSO catalog for Lupus3 (from Comeron F.
2008hsf2.book..295C 2008hsf2.book..295C; see Appendix A.3.)
table6.dat 49 363 YSO catalog for IC348 (mainly from Lada et al.,
Cat. J/AJ/131/1574 and Muench et al.,
Cat. J/AJ/134/411; see Appendix A.4.)
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Note on table4.dat: This list includes the 226 known members of ChaI discussed
in Luhman (2007, Cat. J/ApJS/173/104). We also add the eight new members
identified in Luhman & Muench (2008, Cat. J/ApJ/684/654) and four new members
identified in Luhman et al. (2008, Cat. J/ApJ/675/1375). Some sources were
excluded and four new members were added: RXJ1129.2-7546, RXJ1108.8-7519a,
RXJ1108.8-7519b, and Cha-MMS1, for which proper motion measurements indicate
that they are likely ChaI members. See Appendix A.2. for further explanations.
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/A+A/537/A135 : X-ray view of IC348 (Stelzer+, 2012)
J/ApJS/196/4 : New young star candidates in Taurus-Auriga (Rebull+, 2011)
J/ApJ/703/1964 : Spectra of three nearby star-forming regions (Furlan+, 2009)
J/ApJ/684/654 : Low-mass members of Chamaeleon I (Luhman+, 2008)
J/ApJ/675/1375 : IRAC/MIPS photometry in Cha I (Luhman+, 2008)
J/ApJS/177/551 : Spitzer c2d survey of Lupus dark clouds (Merin+, 2008)
J/AJ/134/411 : Properties of IC 348 members (Muench+, 2007)
J/ApJS/173/104 : Stellar population in Chamaeleon I (Luhman, 2007)
J/AJ/131/1574 : Infrared photometry of IC348 members (Lada+, 2006)
J/A+A/454/595 : X-ray emission of T Tau stars in Lupus 3 (Gondoin, 2006)
J/ApJ/578/914 : Low-mass stars in Taurus (Hartmann, 2002)
Byte-by-byte Description of file: table[34].dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Hour of Right Ascension (J2000)
4- 5 I2 min RAm Minute of Right Ascension (J2000)
7- 11 F5.2 s RAs Second of Right Ascension (J2000)
13 A1 --- DE- Sign of Declination (J2000)
14- 15 I2 deg DEd Degree of Declination (J2000)
17- 18 I2 arcmin DEm Arcminute of Declination (J2000)
20- 24 F5.2 arcsec DEs Arcsecond of Declination (J2000)
26- 42 A17 --- 2MASS Source designation (JHHMMSSss+DDMMSSs)
44- 60 A17 --- OName Other designation
62- 66 A5 --- SpType MK spectral type
68 A1 --- f_SpType [c] Flag on SpType (1)
70- 74 F5.3 Msun Mass Estimated mass from Appendix C procedure
76 I1 --- Group ?=- YSO MST group number (G1)
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Note (1): Spectral type and corresponding mass based on estimate from
bolometric luminosity measured. Values should only be used within the
following ranges: <K6, K6-M3.5, M3.5-M6, and M6-M8 corresponding to
mass ranges of: >0.906, 0.906-0.3345, 0.3345-0.096, and
0.096-0.031M☉ respectively.
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Byte-by-byte Description of file: table[56].dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Hour of Right Ascension (J2000)
4- 5 I2 min RAm Minute of Right Ascension (J2000)
7- 11 F5.2 s RAs Second of Right Ascension (J2000)
13 A1 --- DE- Sign of the Declination (J2000)
14- 15 I2 deg DEd Degree of Declination (J2000)
17- 18 I2 arcmin DEm Arcminute of Declination (J2000)
20- 24 F5.2 arcsec DEs Arcsecond of Declination (J2000)
26- 35 A10 --- Name Source designation
37- 41 A5 --- SpType MK spectral type
43- 47 F5.3 Msun Mass Estimated mass from Appendix C procedure
49 I1 --- Group ?=- YSO MST group number (G1)
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Global notes:
Note (G1): Group defined from a Minimal Spanning Tree (MST) algorithm,
see Section 3 and Appendix D.1 for details.
Summary of group properties, as in table 1:
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Region Group Center RA (J2000) DE N <Mass> Size(pc) Description
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Taurus 1 4:14:24.60 +28:07:27.35 20 0.426 0.516 B209
Taurus 2 4:18:51.09 +28:20:59.67 30 0.398 0.448 L1495E
Taurus 3 4:21:27.45 +27:00:10.82 19 0.398 0.481 B213
Taurus 4 4:32:13.94 +18:14:58.83 24 0.684 0.498 L1551
Taurus 5 4:32:32.88 +24:19:32.69 14 0.684 0.508 L1529
Taurus 6 4:35:15.69 +22:53:24.44 31 0.398 0.511 L1536
Taurus 7 4:40:35.48 +25:49:22.52 24 0.575 0.506 L1527
Taurus 8 4:55:47.60 +30:28:09.47 16 0.213 0.475 L1517
Lupus3 1 16:08:32.14 -39:05:55.91 36 0.271 0.320 Lupus3-main
ChaI 1 11:03:12.71 -77:24:18.35 12 0.201 0.209 ChaI-Southwest
ChaI 2 11:08:43.91 -77:31:28.48 96 0.236 0.190 ChaI-South
ChaI 3 11:09:57.17 -76:33:57.00 43 0.303 0.188 ChaI-North
IC348 1 3:44:33.75 +32:08:58.09 186 0.271 0.082 IC348-main
IC348 2 3:44:32.89 +32:15:32.61 11 0.335 0.083 IC348-North
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 23-Aug-2012