J/ApJ/775/63 Gould's Belt VLA Survey. I. Ophiuchus complex (Dzib+, 2013)
The Gould's Belt Very Large Array Survey.
I. The Ophiuchus complex.
Dzib S.A., Loinard L., Mioduszewski A.J., Rodriguez L.F., Ortiz-Leon G.N.,
Pech G., Rivera J.L., Torres R.M., Boden A.F., Hartmann L., Evans II N.J.,
Briceno C., Tobin J.
<Astrophys. J., 775, 63 (2013)>
=2013ApJ...775...63D 2013ApJ...775...63D
ADC_Keywords: Radio continuum ; Cross identifications ; Infrared sources ;
X-ray sources ; YSOs ; Spectral types
Keywords: astrometry; magnetic fields; radiation mechanisms: non-thermal;
radio continuum: stars; techniques: interferometric
Abstract:
We present large-scale (∼2000arcmin2), deep (∼20µJy),
high-resolution (∼1") radio observations of the Ophiuchus star-forming
complex obtained with the Karl G. Jansky Very Large Array at
λ=4 and 6cm. In total, 189 sources were detected, 56 of them
associated with known young stellar sources, and 4 with known
extragalactic objects; the other 129 remain unclassified, but most of
them are most probably background quasars. The vast majority of the
young stars detected at radio wavelengths have spectral types K or M,
although we also detect four objects of A/F/B types and two brown
dwarf candidates. At least half of these young stars are non-thermal
(gyrosynchrotron) sources, with active coronas characterized by high
levels of variability, negative spectral indices, and (in some cases)
significant circular polarization. As expected, there is a clear
tendency for the fraction of non-thermal sources to increase from the
younger (Class 0/I or flat spectrum) to the more evolved (Class III or
weak line T Tauri) stars. The young stars detected both in X-rays and
at radio wavelengths broadly follow a Gudel-Benz relation, but with a
different normalization than the most radioactive types of stars.
Finally, we detect a ∼70mJy compact extragalactic source near the
center of the Ophiuchus core, which should be used as gain calibrator
for any future radio observations of this region.
Description:
The observations were obtained with the Karl G. Jansky VLA of the
National Radio Astronomy Observatory. Two frequency sub-bands, each
1GHz wide, and centered at 4.5 and 7.5GHz, respectively, were recorded
simultaneously. The observations were obtained on three different
epochs (2011 February 17/19, April 3/4, and May 4/6) typically
separated from one another by a month.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 112 189 Radio sources detected in Ophiuchus
table3.dat 99 134 Radio sources with known counterparts
table5.dat 54 56 Young stellar objects detected in the radio
observations
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See also:
II/311 : WISE All-Sky Data Release (Cutri+ 2012)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
J/ApJS/211/3 : NIR photometry variability in ρ Oph (Parks+, 2014)
J/ApJ/751/22 : Candidates of the ρ Oph cluster (Barsony+, 2012)
J/AJ/142/140 : Optical spectroscopy of ρ Oph stars. II. (Erickson+, 2011)
J/ApJ/724/835 : The Spitzer c2d survey of WTTSs. III. (Wahhaj+, 2010)
J/A+A/519/A34 : YSOs in DROXO (Deep rho Oph XMM obs.) (Pillitteri+, 2010)
J/ApJ/719/550 : Deep NIR imaging of ρ Oph cloud core (Marsh+, 2010)
J/ApJ/712/925 : Transition circumstellar disks in Ophiuchus (Cieza+, 2010)
J/A+A/515/A75 : Low-mass pop. in ρ Oph cloud (Alves de Oliveira+, 2010)
J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)
J/ApJ/703/1964 : Spectra of three nearby star-forming regions (Furlan+, 2009)
J/ApJ/692/973 : Protostars in Perseus, Serpens and Ophiuchus (Enoch+, 2009)
J/ApJ/683/822 : Star formation in Ophiuchus and Perseus II. (Jorgensen+, 2008)
J/ApJ/671/1800 : SCUBA observations of ρ Oph cloud (Andrews+, 2007)
J/ApJ/667/308 : Weak-line T Tauri in Spitzer c2d Survey. II. (Cieza+, 2007)
J/A+A/460/695 : Search for Associations Containing Young stars (Torres+, 2006)
J/A+A/447/609 : 1.2mm continuum observations in rho Oph cloud (Stanke+, 2006)
J/AJ/130/1733 : Optical spectroscopy of ρ Oph stars (Wilking+, 2005)
J/A+A/429/963 : XMM-Newton observation of the rho Oph cloud (Ozawa+, 2005)
J/ApJ/613/393 : X-ray and radio sources in ρ Oph Core A (Gagne+, 2004)
J/PASJ/55/653 : Chandra X-ray flares in rho Ophiuchi (Imanishi+, 2003)
J/A+A/359/113 : X-ray and IR study of Rho Oph dark cloud (Grosso+, 2000)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- GBS-VLA Radio source name (JHHMMSS.ss+DDMMSS.s)
21 A1 --- l_F4.5 Limit flag on F4.5
22- 28 E7.3 mJy F4.5 [0.05/71.1] 4.5GHz flux
30- 36 E7.3 mJy e_F4.5 [0.007/1.5]? Error from statistical noise in
the image
38- 44 E7.3 mJy s_F4.5 [0.003/3.6]? Systematic uncertainty of 5% (1)
46 A1 --- l_v4.5 Limit flag on v4.5
48- 51 F4.1 % v4.5 [2/97]? Variability of the source at 4.5GHz (2)
52 A1 --- f_v4.5 [a] low S/N (3)
54- 57 F4.1 % e_v4.5 [0.1/31]? v4.5 uncertainty
59 A1 --- l_F7.5 Limit flag on F7.5
61- 67 E7.3 mJy F7.5 [0.04/71]? 7.5GHz flux
69- 75 E7.3 mJy e_F7.5 [0.005/4]? Error from statistical noise in
the image
77- 83 E7.3 mJy s_F7.5 [0.002/3.5]? Systematic uncertainty of 5% (1)
85 A1 --- l_v7.5 Limit flag on v7.5
87- 90 F4.1 % v7.5 [5/98]? Variability of the source at 7.5GHz (2)
91 A1 --- f_v7.5 [a] low S/N (3)
93- 96 F4.1 % e_v7.5 [0.1/37.5]? v7.5 uncertainty
98 A1 --- l_alpha Limit flag on SpInd
100-104 F5.2 --- alpha [-2.7/3.4]? Radio spectral index α from
the fluxes measured in each sub-band
(Fν∝να)
106-109 F4.2 --- e_alpha [0/0.9]? alpha uncertainty (4)
111-112 A2 --- Ex? Ex: Extended
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Note (1): Systematic uncertainty of 5% resulting from possible errors in the
absolute flux calibration.
Note (2): An estimate of the level of variability of the sources was measured by
comparing the fluxes measured at the three epochs. Specifically, we
calculated, for each source and at each frequency, the difference
between the highest and lowest measured fluxes, and normalized by the
maximum flux.
Note (3):
a = Source not detected at three times the noise level on individual epochs,
but detected on the image of the concatenated epochs.
Note (4): To calculate the errors on the spectral indices, the two sources of
errors (statistical and systematic) on the flux at each frequency
were added in quadrature and the final error was obtained using
standard error propagation theory.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- GBS-VLA Radio source name (JHHMMSS.ss+DDMMSS.s)
21- 43 A23 --- OName Other name
45- 65 A21 --- XID X-ray identifier (1)
67 A1 --- SST? Y: in Evans et al. 2009, J/ApJS/181/321
69 A1 --- 2M? Y: in Cutri et al. 2003, II/246
71 A1 --- WISE? Y: in Cutri et al. 2012, II/311
73 A1 --- f_GBS-VLA [a] Flag on J162722.96-242236.6 (2)
75- 94 A20 --- Radio Radio identifier (3)
96- 99 A4 --- Type Object type (YSO, YSO? or E=extragalactic)
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Note (1): X-ray identifier from:
ROXRA = Grosso et al. 2000, J/A+A/359/113
A and BF = Imanishi et al. 2003, J/PASJ/55/653 (<[INT2003] AA-NN> in Simbad)
DROXO = Pillitteri et al. 2010, J/A+A/519/A34
ROX = Montmerle et al. 1983ApJ...269..182M 1983ApJ...269..182M
ROXs = Bouvier & Appenzeller 1992A&AS...92..481B 1992A&AS...92..481B
1RXS = Voges et al. 1999, IX/10
RX = Martin et al. 1998MNRAS.300..733M 1998MNRAS.300..733M
(<[MMG98] RX JHHMM.m+DDMMa> in Simbad)
Note (2):
a = For GBDS-VLA J162722.96-242236.6, 2MASS, and SST data from
Marsh et al. (2010, J/ApJ/719/550; <[MPK2010b] NNNNN> in Simbad).
Note (3): Radio identifier from:
ROC and ROS = Andre et al. 1987AJ.....93.1182A 1987AJ.....93.1182A
GDS = Gagne et al. 2004, J/ApJ/613/393
NVSS = Condon et al. 1998, VIII/65
LFAM = Leous et al. 1991ApJ...379..683L 1991ApJ...379..683L
SFAM = Stine et al. 1988AJ.....96.1394S 1988AJ.....96.1394S
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- GBS-VLA Radio source name (JHHMMSS.ss+DDMMSS.s)
21 A1 --- f_GBS-VLA [c] possible knot (1)
23- 27 A5 --- SpT MK spectral type
29- 41 A13 --- Class Classification from SED (FS=Faint spectrum)
43 A1 --- Var? Y: source variability >50% in at least one
frequency; N when it is lower
45 A1 --- Pol? Y: circular polarization is detected (2)
47 A1 --- alph? Flat, Negative or Positive spectral index (3)
49 A1 --- X? Y: X-ray flux reported in the literature
51- 54 A4 --- Ref Reference(s) (4)
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Note (1):
c = This source corresponds to VLA1623B; as discussed in the text, it may be
a young star or an outflow knot feature.
Note (2): Sources in the outer fields for which the polarization could not be
assessed are blanks.
Note (3): Code for the spectral index α as follows:
P = spectral index higher than 0.2
F = between -0.2 and +0.2
N = spectral index lower than -0.2
Note (4): Reference as follows:
1 = Wilking et al. 2005, J/AJ/130/1733
2 = Gagne et al. 2004, J/ApJ/613/393
3 = Murillo & Lai 2013ApJ...764L..15M 2013ApJ...764L..15M
4 = Andre et al. 1993ApJ...406..122A 1993ApJ...406..122A
5 = Alves de Oliveira et al. 2010, J/A+A/515/A75
6 = Marsh et al. 2010, J/ApJ/719/550
7 = Pillitteri et al. 2010, J/A+A/519/A34
8 = McClure et al. 2010ApJS..188...75M 2010ApJS..188...75M
9 = Cieza et al. 2007, J/ApJ/667/308
10 = Wilking et al. 2001ApJ...551..357W 2001ApJ...551..357W
11 = Martin et al. 1998MNRAS.300..733M 1998MNRAS.300..733M
12 = Wahhaj et al. 2010, J/ApJ/724/835
13 = Bouvier & Appenzeller 1992A&AS...92..481B 1992A&AS...92..481B
14 = Torres et al. 2006, J/A+A/460/695
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History:
From electronic version of the journal
References:
Ortiz-Leon et al. II. Serpens region. 2015ApJ...805....9O 2015ApJ...805....9O J/ApJ/805/9
Kounkel et al. III. Orion region. 2014ApJ...790...49K 2014ApJ...790...49K J/ApJ/790/49
Dzib et al. IV. Taurus-Auriga. 2015ApJ...801...91D 2015ApJ...801...91D J/ApJ/801/91
Pech et al. V. Perseus region. 2016ApJ...818..116P 2016ApJ...818..116P
(End) Emmanuelle Perret [CDS] 10-Mar-2015