J/ApJ/827/96 WISE census of YSOs in Canis Major (Fischer+, 2016)
A WISE census of young stellar objects in Canis Major.
Fischer W.J., Padgett D.L., Stapelfeldt K.L., Sewilo M.
<Astrophys. J., 827, 96-96 (2016)>
=2016ApJ...827...96F 2016ApJ...827...96F (SIMBAD/NED BibCode)
ADC_Keywords: YSOs ; Photometry, infrared
Keywords: circumstellar matter; infrared: stars; stars: formation;
stars: protostars
Abstract:
With the Wide-field Infrared Survey Explorer (WISE), we searched for
young stellar objects (YSOs) in a 100deg2 region centered on the
lightly studied Canis Major star-forming region. Applying stringent
magnitude cuts to exclude the majority of extragalactic contaminants,
we find 144 Class I candidates and 335 Class II candidates. The
sensitivity to Class II candidates is limited by their faintness at
the distance to Canis Major (assumed as 1000pc). More than half the
candidates (53%) are found in 16 groups of more than four members,
including four groups with more than 25 members each. The ratio of
Class II to Class I objects, NII/NI, varies from 0.4 to 8.3 in
just the largest four groups. We compare our results to those
obtainable with combined Two Micron All Sky Survey and post-cryogenic
Spitzer Space Telescope data; the latter approach recovers missing
Class II sources. Via a comparison to protostars characterized with
the Herschel Space Observatory, we propose new WISE color criteria for
flat-spectrum and Class 0 protostars, finding 80 and 7 of these,
respectively. The distribution of YSOs in CMa OB1 is consistent with
supernova-induced star formation, although the diverse NII/NI
ratios are unexpected if this parameter traces age and the YSOs are
due to the same supernova. Less massive clouds feature larger
NII/NI ratios, suggesting that initial conditions play a role in
determining this quantity.
Description:
The AllWISE catalog (see II/328) combines data from the cryogenic and
post-cryogenic phases of the initial WISE mission, covering the
approximately 1yr period from 2010 January to 2011 January. We
searched AllWISE in the 10°x10° square centered at 106.67°
RA and -11.29° DEC.
These are the approximate coordinates of HD53974 (FN CMa), a star that
is roughly at the center of the CMa OB1 association. In the cryogenic
mission, WISE obtained four-band photometry in this region between
2010 March 29 and April 11. Additional W1 and W2 photometry was
obtained during the post-cryogenic mission, between 2010 October 7 and
20.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 134 479 WISE YSO candidates
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See also:
II/328 : AllWISE Data Release (Cutri+ 2013)
II/311 : WISE All-Sky Data Release (Cutri+ 2012)
J/ApJS/224/5 : Herschel Orion Protostar Survey (HOPS): SEDs (Furlan+, 2016)
J/AJ/150/100 : WISE YSO cand. near σ and λ Ori (Koenig+, 2015)
J/ApJ/787/107 : Spatial structure of young stellar clusters. I. (Kuhn+, 2014)
J/ApJ/772/45 : Hi-GAL obs.: star formation in the 3rd quadrant (Elia+, 2013)
J/ApJ/767/36 : APEX observations of HOPS protostars (Stutz+, 2013)
J/AJ/145/94 : Protostar luminosities from 2 Spitzer surveys (Dunham+, 2013)
J/A+A/547/A49 : Herschel EPoS: high-mass overview (Ragan+, 2012)
J/ApJS/184/18 : Spitzer survey of young stellar clusters (Gutermuth+, 2009)
J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)
J/ApJ/693/L81 : Extinction in star-forming regions (McClure, 2009)
J/PASJ/56/313 : 13CO survey of Mon + CMa molecular clouds (Kim+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- WISEA WISE identifier (JHHMMSS.ss+DDMMSS.s)
21- 29 F9.5 deg RAdeg Right Ascension in decimal degrees (J2000)
31- 39 F9.5 deg DEdeg Declination in decimal degrees (J2000)
41- 46 F6.3 mag Jmag [9.3/18.8]? 2MASS J band magnitude
48- 52 F5.3 mag e_Jmag [0.02/0.3]? Uncertainty in Jmag (1)
54- 59 F6.3 mag Hmag [8.3/17.5]? 2MASS H band magnitude
61- 65 F5.3 mag e_Hmag [0.02/0.3]? Uncertainty in Hmag (1)
67- 72 F6.3 mag Ksmag [7.4/15.2]? 2MASS Ks band magnitude
74- 78 F5.3 mag e_Ksmag [0.01/0.2]? Uncertainty in Ksmag (1)
80- 85 F6.3 mag 3.4mag [6.3/18.6] WISE W1 3.4 micron band magnitude
87- 91 F5.3 mag e_3.4mag [0.01/0.6] Uncertainty in 3.4mag
93- 98 F6.3 mag 4.6mag [4.4/14.4] WISE W2 4.6 micron band magnitude
100-104 F5.3 mag e_4.6mag [0.01/0.2] Uncertainty in 4.6mag
106-111 F6.3 mag 12mag [1.5/11.7] WISE W3 12 micron band magnitude
113-117 F5.3 mag e_12mag [0.01/0.5]? Uncertainty in 12mag (1)
119-123 F5.3 mag 22mag [0.2/8.9] WISE W4 22 micron band magnitude
125-129 F5.3 mag e_22mag [0.005/0.5]? Uncertainty in 22mag (1)
131-132 A2 --- Class YSO classification ("I": 144 sources or
"II": 335 sources)
134 A1 --- Q Quality code from visual inspection (2)
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Note (1): Cases with an entry for the magnitude and no entry for the
uncertainty are upper limits.
Note (2): Quality code as follows:
y = yes: unambiguous detection; contamination likely insignificant
- 292 sources;
b = binary: unambiguous detection; contamination from nearby point
source(s) may be significant - 95 sources;
f = faint: unambiguous point source in W1 and W2; nothing visible in W4;
no obvious contaminants in W3 or W4 - 53 sources;
c = contaminated: unambiguous point source in W1 and W2; may be a point
source in W3 and W4, but probably contaminated by nearby point source
or nebulosity - 38 sources;
n = no: point source not seen in any band; probably an artifact but not
flagged; 1 source.
Sources with b, f, or c codes are likely YSOs, but the photometry may
be less accurate. See Section 3.3 for further details.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 25-Nov-2016