J/ApJ/654/338 Spitzer photometry in W3 molecular cloud (Ruch+, 2007)
Spitzer observations of the giant molecular cloud W3.
Ruch G.T., Jones T.J., Woodward C.E., Polomski E.F., Gehrz R.D.,
Megeath S.T.
<Astrophys. J., 654, 338-346 (2007)>
=2007ApJ...654..338R 2007ApJ...654..338R
ADC_Keywords: Molecular clouds ; Stars, pre-main sequence ; Photometry, infrared
Keywords: infrared: ISM - infrared: stars - ISM: individual (W3) -
stars: formation - stars: pre-main-sequence - stars: statistics
Abstract:
We present new images of the giant molecular cloud W3 obtained with
the Infrared Array Camera (IRAC) and the Multiband Imaging Photometer
for Spitzer (MIPS) on board the Spitzer Space Telescope. The images
encompass the star forming regions W3 Main, W3(OH), and a region that
we refer to as the Central Cluster, which encloses the emission nebula
IC 1795. We present a star count analysis of the point sources
detected in W3. The star count analysis shows that the stellar
population of the Central Cluster, when compared to that in the
background, contains an over density of sources. The Central Cluster
also contains an excess of sources with colors consistent with Class
II young stellar objects (YSOs). An analysis of the color-color
diagrams also reveals a large number of Class II YSOs in the Central
Cluster. Our results suggest that an earlier epoch of star formation
created the Central Cluster, created a cavity, and triggered the
active star formation in the W3 Main and W3(OH) regions. We also
detect a new outflow and its candidate exciting star.
Description:
W3 was observed with IRAC on 2004 January 10 UT under our GTO program,
PID 127.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 94 295 IRAC magnitudes of sources detected in all 4 bands
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [RJW2007] The IRAC identification number
5- 20 A16 --- 2MASS The 2MASS identification number
(HHMMSSss+DDMMSSs)
22- 30 F9.6 deg RAdeg Right Ascension in decimal degrees (J2000)
32- 40 F9.6 deg DEdeg Declination in decimal degrees (J2000)
42- 46 F5.2 mag 3.6mag The IRAC 3.6 micron magnitude
48- 51 F4.2 mag e_3.6mag Uncertainty in 3.6mag
53- 57 F5.2 mag 4.5mag The IRAC 4.5 micron magnitude
59- 62 F4.2 mag e_4.5mag Uncertainty in 4.5mag
64- 68 F5.2 mag 5.8mag The IRAC 5.8 micron magnitude
70- 73 F4.2 mag e_5.8mag Uncertainty in 5.8mag
75- 79 F5.2 mag 8.0mag The IRAC 8.0 micron magnitude
81- 84 F4.2 mag e_8.0mag Uncertainty in 8.0mag
86- 89 F4.2 mag 24mag ? The MIPS 24.0 micron magnitude
91- 94 F4.2 mag e_24mag ? Uncertainty in 24.0mag
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 25-Nov-2008