J/A+A/587/A153 VISION I. VISTA Orion A Survey (Meingast+, 2016)
VISION - Vienna survey in Orion. I. VISTA Orion A Survey.
Meingast S., Alves J., Mardones D., Teixeira P.S., Lombardi M.,
Grosschedl J., Ascenso J., Bouy H., Forbrich J., Goodman A., Hacar A.,
Hasenberger B., Kainulainen J., Kubiak K., Lada C., Lada E., Moitinho A.,
Petr-gotzens M., Rodrigues L., Roman-zuniga C.G.
<Astron. Astrophys., 587, A153 (2016)>
=2016A&A...587A.153M 2016A&A...587A.153M (SIMBAD/NED BibCode)
ADC_Keywords: Infrared sources ; Photometry, infrared ; Surveys
Keywords: techniques: image processing - methods: data analysis -
stars: formation - stars: pre-main sequence
Abstract:
Orion A hosts the nearest massive star factory, thus offering a unique
opportunity to resolve the processes connected with the formation of
both low- and high-mass stars. Here we present the most detailed and
sensitive near-infrared (NIR) observations of the entire molecular
cloud to date. With the unique combination of high image quality,
survey coverage, and sensitivity, our NIR survey of Orion A aims at
establishing a solid empirical foundation for further studies of this
important cloud. In this first paper we present the observations, data
reduction, and source catalog generation. To demonstrate the data
quality, we present a first application of our catalog to estimate the
number of stars currently forming inside Orion A and to verify the
existence of a more evolved young foreground population. We used the
European Southern Observatory's (ESO) Visible and Infrared Survey
Telescope for Astronomy (VISTA) to survey the entire Orion A molecular
cloud in the NIR J, H, and KS bands, covering a total of
∼18.3deg2. We implemented all data reduction recipes independently
of the ESO pipeline. Estimates of the young populations toward Orion A
are derived via the KS-band luminosity function. Our catalog (799995
sources) increases the source counts compared to the Two Micron All
Sky Survey by about an order of magnitude. The 90% completeness limits
are 20.4, 19.9, and 19.0mag in J, H, and KS, respectively. The
reduced images have 20% better resolution on average compared to
pipeline products. We find between 2300 and 3000 embedded objects in
Orion A and confirm that there is an extended foreground population
above the Galactic field, in agreement with previous work. The Orion A
VISTA catalog represents the most detailed NIR view of the nearest
massive star-forming region and provides a fundamental basis for
future studies of star formation processes toward Orion.
Description:
VISION is a near-infrared survey of the entire Orion A molecular
cloud, the nearest massive star forming region. It was conducted with
the ESO VISTA telescope at Paranal and covers about 18 deg2 of the
high column-density areas of the molecular cloud in the J, H, and Ks
bands. The source catalog contains about 800000 sources. In addition
an extinction-free control field was observed at similar galactic
latitude. The source catalog for the control field contains about
90000 sources.
This data set also includes the identification of YSO and galaxy
cluster candidates as presented in the survey paper.
Image data (HiPS resource) are available at
http://alasky.u-strasbg.fr/VISTA/VISTA-Orion-A-Colored/
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
science.dat 259 799995 *Orion A photometry
control.dat 259 93909 Control field photometry
yso.dat 259 6 New YSO candidates identified in VISION
galaxy.dat 31 10 New galaxy cluster candidates in VISION
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Note on science.dat: Image data (HiPS resource) are available at
http://alasky.u-strasbg.fr/VISTA/VISTA-Orion-A-Colored/ .
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Byte-by-byte Description of file: science.dat control.dat yso.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- VISION VISION source identifier, HHMMSSss+DDMMSSs (1)
18- 27 F10.6 deg RAdeg Right ascension (J2000.0)
29- 38 F10.6 deg DEdeg Declination (J2000.0)
40- 45 F6.3 mag Jmag ? J band magnitude
47- 51 F5.3 mag e_Jmag ? J band magnitude error
53- 58 F6.3 mag Hmag ? H band magnitude
60- 64 F5.3 mag e_Hmag ? H band magnitude error
66- 71 F6.3 mag Ksmag ? Ks band magnitude
73- 77 F5.3 mag e_Ksmag ? Ks band magnitude error
79 I1 --- ClassCog [0/1] Curve of growth morphology class
81- 85 F5.3 --- ClassSex Sextractor morphology class
87- 95 F9.3 d JMJD ? Effective MJD J band
97-105 F9.3 d HMJD ? Effective MJD H band
107-115 F9.3 d KsMJD ? Effective MJD Ks band
117-120 I4 s JExpTime ? Effective exposure time J band
122-125 I4 s HExpTime ? Effective exposure time H band
127-130 I4 s KsExpTime ? Effective exposure time Ks band
132-136 F5.2 arcsec JFWHM ? Source FWHM J band
138-142 F5.2 arcsec HFWHM ? Source FWHM H band
144-148 F5.2 arcsec KsFWHM ? Source FWHM Ks band
150-153 F4.2 arcsec JSeeing ? Local seeing conditions J band
155-158 F4.2 arcsec HSeeing ? Local seeing conditions H band
160-163 F4.2 arcsec KsSeeing ? Local seeing conditions Ks band
165-166 I2 --- JCov ? Number of exposures J band
168-169 I2 --- HCov ? Number of exposures H band
171-172 I2 --- KsCov ? Number of exposures Ks band
174-177 F4.2 arcsec Japer ? Aperture radius J band
179-182 F4.2 arcsec Haper ? Aperture radius H band
184-187 F4.2 arcsec Ksaper ? Aperture radius Ks band
189-204 A16 --- J2massId 2MASS identifier J band
206-221 A16 --- H2massId 2MASS identifier H band
223-238 A16 --- Ks2massId 2MASS identifier Ks band
240-245 A6 --- Jorigin Catalog origin J band (VISION or 2MASS)
247-252 A6 --- Horigin Catalog origin H band (VISION or 2MASS)
254-259 A6 --- Ksorigin Catalog origin Ks band (VISION or 2MASS)
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Note (1): The VISION identifier is constructed in the same way as the 2MASS
identifier.
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Byte-by-byte Description of file: galaxy.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Galaxy cluster name
11- 20 F10.6 deg RAdeg Right ascension (J2000.0)
22- 31 F10.6 deg DEdeg Declination (J2000.0)
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Acknowledgements:
Stefan Meingast, stefan.meingast(at)univie.ac.at
Joao Alves, joao.alves(at)univie.ac.at
(End) Stefan Meingast [Vienna Univ. Austria], Patricia Vannier [CDS] 10-Nov-2016