J/ApJ/697/787 The NAN complex. I. IRAC observations (Guieu+, 2009)
The North American and Pelican nebulae.
I. IRAC observations.
Guieu S., Rebull L.M., Stauffer J.R., Hillenbrand L.A., Carpenter J.M.,
Noriega-Crespo A., Padgett D.L., Cole D.M., Carey S.J., Stapelfeldt K.R.,
Strom S.E.
<Astrophys. J., 697, 787-800 (2009)>
=2009ApJ...697..787G 2009ApJ...697..787G
ADC_Keywords: YSOs ; Photometry, infrared ; Nebulae ; Photometry, VRI
Keywords: circumstellar matter - infrared: ISM - infrared: stars - ISM: clouds -
ISM: individual (NGC 7000, IC 5070) - stars: formation -
stars: pre-main sequence
Abstract:
We present a 9deg2 map of the North American and Pelican Nebulae
regions obtained in all four Infrared Array Camera (IRAC) channels
with the Spitzer Space Telescope. The resulting photometry is merged
with that at JHKs from Two Micron All Sky Survey and a more spatially
limited BVI survey from previous ground-based work. We use a mixture
of color-color diagrams to select a minimally contaminated set of more
than 1600 objects that we claim are young stellar objects (YSOs)
associated with the star-forming region. Because our selection
technique uses infrared excess as a requirement, our sample is
strongly biased against inclusion of Class III YSOs. The distribution
of IRAC spectral slopes for our YSOs indicates that most of these
objects are Class II, with a peak toward steeper spectral slopes but a
substantial contribution from a tail of Flat spectrum and Class I type
objects. By studying the small fraction of the sample that is
optically visible, we infer a typical age of a few Myr for the
low-mass population. The young stars are clustered, with about a third
of them located in eight clusters that are located within or near the
LDN 935 dark cloud. Half of the YSOs are located in regions with
surface densities higher than 1000YSOs/deg2. The Class I objects are
more clustered than the Class II stars.
Description:
The Spitzer/IRAC observations of the NAN (The North American (NGC 7000)
and Pelican (IC 5070) Nebulae) complex were obtained as part of the
Cycle-2 program 20015 (PI: L. Rebull) in 2006 August 9-11. Additional
observations of the "corners" of the map were obtained as part of
program 462 in 2007 November 15-27.
BVI images were obtained with the KPNO 0.9m telescope on four
photometric nights in 1997 June.
Astrometry was obtained using the Hubble Space Telescope Guide Star
Catalog and the TASTROM task and is estimated accurate to <0.3"
(1σ) based on stars in the overlap regions.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 142 1657 Table of YSO candidates
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/196 : Vilnius Photometry in two Nebulae (Straizys et al., 1993)
J/ApJS/193/25 : The NAN complex. II. MIPS observations (Rebull+, 2011)
J/BaltA/18/141 : North America/Pelican red clump giants ugriJHK (Straizys+,
2009)
J/BaltA/17/1 : Infrared photometry in GL490 star-forming region (Straizys+
2008)
J/BaltA/17/125 : Interstellar reddening in 3 HII regions (Straizys+, 2008)
J/BaltA/15/483 : Vilnius photometry in LDN 935 (Laugalys+, 2006)
J/A+A/419/149 : UBV(I)c photometry of NGC 6996 (Villanova+, 2004)
J/A+AS/104/557 : uvby-beta photometry in star-forming regions (Terranegra+
1994)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [SST] for Spitzer Space Telescope
5- 21 A17 --- [GRS2009] The IAU designation
<[GRS2009] SST JHHMMSS.s+DDMMSS.s> in Simbad)
23- 24 I2 h RAh Hour of Right Ascension (J2000)
26- 27 I2 min RAm Minute of Right Ascension (J2000)
29- 34 F6.3 s RAs Second of Right Ascension (J2000)
36 A1 --- DE- Sign of the Declination (J2000)
37- 38 I2 deg DEd Degree of Declination (J2000)
40- 41 I2 arcmin DEm Arcminute of Declination (J2000)
43- 48 F6.3 arcsec DEs Arcsecond of Declination (J2000)
50- 65 A16 --- 2MASS The 2MASS designation (HHMMSSss+DDMMSSs) (1)
67- 72 F6.3 mag Bmag ?=-9.99 The KPNO B band magnitude
74- 79 F6.3 mag Vmag ?=-9.99 The KPNO V band magnitude
81- 86 F6.3 mag Imag ?=-9.99 The KPNO I band magnitude
88- 93 F6.3 mag Jmag ?=-9.99 2MASS J band magnitude
95-100 F6.3 mag Hmag ?=-9.99 2MASS J band magnitude
102-107 F6.3 mag Ksmag ?=-9.99 2MASS Ks band magnitude
109-114 F6.3 mag [3.6] ?=-9.99 Spitzer/IRAC 3.6 micron band magnitude
116-121 F6.3 mag [4.5] ?=-9.99 Spitzer/IRAC 4.5 micron band magnitude
123-128 F6.3 mag [5.8] ?=-9.99 Spitzer/IRAC 5.8 micron band magnitude
130-135 F6.3 mag [8.0] ?=-9.99 Spitzer/IRAC 8.0 micron band magnitude
137-142 F6.3 mag [24] ?=-9.99 Spitzer/MIPS 24 micron band magnitude
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Note (1):
? = source not detected in the 3 2MASS bands.
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Nomenclature Notes:
YSO candidates are <[GRS2009] SST JHHMMSS.s+DDMMSS.s> in Simbad.
History:
From electronic version of the journal
References:
Rebull et al. Paper II. 2011ApJS..193...25R 2011ApJS..193...25R Cat. J/ApJS/193/25
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 11-May-2011