J/AJ/150/191 Infrared photometry of YSOs in Cygnus-X DR15 (Rivera-Galvez+, 2015)
The young stellar population of the Cygnus-X DR15 region.
Rivera-Galvez S., Roman-Zuniga C.G., Jimenez-Bailon E., Ybarra J.E.,
Alves J.F., Lada E.A.
<Astron. J., 150, 191 (2015)>
=2015AJ....150..191R 2015AJ....150..191R (SIMBAD/NED BibCode)
ADC_Keywords: YSOs ; Photometry, infrared
Keywords: infrared: ISM - infrared: stars - stars: formation - X-rays: stars
Abstract:
We present a multi-wavelength study of the young stellar population in
the Cygnus-X DR15 region. We studied young stars that were forming or
recently formed at and around the tip of a prominent molecular pillar
and an infrared dark cloud. Using a combination of ground-based
near-infrared, space-based infrared, and X-ray data, we constructed a
point source catalog from which we identified 226 young stellar
sources, which we classified into evolutionary classes. We studied
their spatial distributions across the molecular gas structures and
identified several groups that possibly belong to distinct young star
clusters. We obtained samples of these groups and constructed K-band
luminosity functions that we compared with those of artificial
clusters, allowing us to make first order estimates of the mean ages
and age spreads of the groups. We used a 13CO(1-0) map to
investigate the gas kinematics at the prominent gaseous envelope of
the central cluster in DR15, and we inferred that the removal of this
envelope is relatively slow compared to other cluster regions, in
which the gas dispersal timescale could be similar or shorter than the
circumstellar disk dissipation timescale. The presence of other groups
with slightly older ages, associated with much less prominent gaseous
structures, may imply that the evolution of young clusters in this
part of the complex proceeds in periods that last 3-5Myr, perhaps
after a slow dissipation of their dense molecular cloud birthplaces.
Description:
Near-infrared images of the Cygnus-X DR15 region were obtained with
the OMEGA 2000 camera at the 3.5m telescope of the Calar Alto
Observatory, atop Sierra de los Filabres in Almeria, Spain, during
the nights of 2010, February 2nd and March 3rd. The data set consists
of 900s co-added exposures in the J, H, and K bands (1.209, 1.648, and
2.208µm, respectively). The seeing values-measured directly from
the average FWHM of stars in the final reduced mosaics-were 1.17,
1.13, and 0.98" in J, H, and K, respectively.
The Spitzer Space Telescope has observed the DR15 cluster with the
IRAC and MIPS detectors as part of the Spitzer Cygnus-X Legacy Survey
(Hora et al. 2009 ASP Conf. Ser., Reionization to Exoplanets:
Spitzer's Growing Legacy ed P. Ogle (San Francisco, CA: ASP) 26;
hereafter CXLS). We obtained archival enhanced product mosaics from
the Spitzer Heritage Archive as well as a photometric catalog
coincident with our region of interest directly from the CXLS Data
Release 1 (DR1). The catalog contains calibrated magnitudes for
sources detected with IRAC in its four cryogenic mission channels
(3.6, 4.5, 5.8, and 8.0µm), as well as in the 24µm channel of
MIPS.
The DR15 cluster was observed with the Imaging Array of the Chandra
Advanced CCD Imaging Spectrometer (ACIS-I) on 2011 January 25
(ObsID12390, P.I. Wright).
We made use of the Five College Radio Observatory (FCRAO) 13CO(1-0)
molecular radio emission map of the south Cygnus-X region from the
study of Schneider et al. (2011A&A...529A...1S 2011A&A...529A...1S).
In Tables 2-4 we list YSO sources identified as Class I, Class II, and
Class III in our region of study.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 175 26 Class I sources in the DR15 region
table3.dat 175 155 Class II sources in the DR15 region
table4.dat 175 45 Class III sources in the DR15 region
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/AJ/148/11 : Infrared photometry in Cygnus-X (Kryukova+, 2014)
J/AJ/144/31 : Spitzer+2MASS photometry of protostar candidates
(Kryukova+, 2012)
J/ApJ/720/679 : Optical spectroscopy in Cygnus X region (Beerer+, 2010)
J/A+A/375/539 : JHK photometry of compact HII regions in Cyg X (Comeron+, 2001)
J/A+A/241/551 : Radio continuum in Cygnus X region (Wendker+ 1991)
Byte-by-byte Description of file: table[234].dat
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Bytes Format Units Label Explanations
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1- 27 A27 --- Name Source name (1)
29- 30 I2 h RAh Hour of Right Ascension (J2000)
32- 33 I2 min RAm Minute of Right Ascension (J2000)
35- 39 F5.2 s RAs Second of Right Ascension (J2000)
41 A1 --- DE- Sign of the Declination (J2000)
42- 43 I2 deg DEd Degree of Declination (J2000)
45- 46 I2 arcmin DEm Arcminute of Declination (J2000)
48- 51 F4.1 arcsec DEs Arcsecond of Declination (J2000)
53- 58 F6.3 mag Jmag [10.9/21.8]? J-band magnitude (1.209µm) (2)
60- 64 F5.3 mag e_Jmag [0.002/0.3]? The 1σ error in Jmag
66 A1 --- f_Jmag [a] Upper limit or very poor photometry from 2MASS
68- 73 F6.3 mag Hmag [9.9/20.1]? H-band magnitude (1.648µm) (2)
75- 79 F5.3 mag e_Hmag [0.005/0.2]? The 1σ error in Hmag
81 A1 --- f_Hmag [a] Upper limit or very poor photometry from 2MASS
83- 88 F6.3 mag Kmag [8.4/18.5]? K-band magnitude (2.208µm) (2)
90- 94 F5.3 mag e_Kmag [0.004/0.2]? The 1σ error in Kmag
96 A1 --- f_Kmag [a] Upper limit or very poor photometry from 2MASS
98-103 F6.3 mag [3.6] [6/16]? Spitzer/IRAC 3.6µm band magnitude (3)
105-109 F5.3 mag e_[3.6] [0.01/0.3]? The 1σ uncertainty in [3.6]
111-116 F6.3 mag [4.5] [5/15]? Spitzer/IRAC 4.5µm band magnitude (3)
118-122 F5.3 mag e_[4.5] [0.01/0.25]? The 1σ uncertainty in [4.5]
124-129 F6.3 mag [5.8] [5/14]? Spitzer/IRAC 5.8µm band magnitude (3)
131-135 F5.3 mag e_[5.8] [0.01/0.7]? The 1σ uncertainty in [5.8]
137-142 F6.3 mag [8.0] [4/14]? Spitzer/IRAC 8.0µm band magnitude (3)
144-148 F5.3 mag e_[8.0] [0.01/4]? The 1σ uncertainty in [8.0]
150-154 F5.3 mag [24] [0.3/8]? Spitzer/MIPS 24µm band magnitude (3)
156-160 F5.3 mag e_[24] [0.01/0.8]? The 1σ uncertainty in [24]
162-166 F5.3 keV Emed [0.8/5.4]? Median energy (4)
168-175 F8.4 aW/m2 Flux [1/217]? Total energy flux
(in units of 10-15erg/cm2/s) (4)
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Note (1): Identifications and positions from our Calar Alto survey at the Centro
Astronomico Hispano Aleman (CAHA) are listed for most cases. The remaining
sources are listed with 2MASS or Spitzer Cygnus-X Legacy Survey (CXLS)
depending on if they were detected in those surveys.
Note (2): From Calar Alto (or 2MASS, cat. II/246, when pertinent,
see Section 2.1).
Note (3): From the Spitzer Cygnus-X Legacy Survey (Hora et al. 2009 ASP Conf.
Ser., Reionization to Exoplanets: Spitzer's Growing Legacy ed P. Ogle
(San Francisco, CA: ASP) 26).
Note (4): For sources detected with Chandra ACIS (that is the case for all Class
III sources).
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History:
From electronic version of the journal
(End) Sylvain Guehenneux [CDS] 21-Jun-2016