J/ApJ/805/9 Gould's Belt VLA Survey. II. Serpens region (Ortiz-Leon+, 2015)
The Gould's Belt Very Large Array survey.
II. The Serpens region.
Ortiz-Leon G.N., Loinard L., Mioduszewski A.J., Dzib S.A., Rodriguez L.F.,
Pech G., Rivera J.L., Torres R.M., Boden A.F., Hartmann L., Evans Ii N.J.,
Briceno C., Tobin J., Kounkel M.A., Gonzalez-lopezlira R.A.
<Astrophys. J., 805, 9 (2015)>
=2015ApJ...805....9O 2015ApJ...805....9O
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 deep (∼17µJy) radio continuum observations of the
Serpens molecular cloud, the Serpens south cluster, and the W40 region
obtained using the Very Large Array in its A configuration. We detect
a total of 146 sources, 29 of which are young stellar objects (YSOs),
2 of which are BV stars, and 5 more of which are associated with
phenomena related to YSOs. Based on their radio variability and
spectral index, we propose that about 16 of the remaining 110
unclassified sources are also YSOs. For approximately 65% of the known
YSOs detected here as radio sources, the emission is most likely
non-thermal and related to stellar coronal activity. As also recently
observed in Ophiuchus, our sample of YSOs with X-ray counterparts lies
below the fiducial Guedel & Benz (1993ApJ...405L..63G 1993ApJ...405L..63G) relation.
Finally, we analyze the proper motions of nine sources in the W40
region. This allows us to better constrain the membership of the radio
sources in the region.
Description:
The Serpens molecular cloud and the Serpens South cluster were
observed in the same observing sessions on three different epochs
(2011 June 17, July 19, and September 12 UT), using 25 and 4
pointings, respectively, with the Jansky Very Large Array (JVLA) at
4.5 and 4.5GHz.
The W40 region, on the other hand, was only observed on two epochs
(2011 June 17 and July 16), using 13 pointings.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 83 146 Radio sources detected in Serpens
table3.dat 107 77 Radio sources with known counterparts
table6.dat 49 29 Young stellar objects detected in the radio
observations
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See also:
VII/244 : Atlas and Catalog of Dark Clouds (Dobashi+, 2005)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
J/AJ/149/103 : Spectroscopy of candidate YSOs in Serpens (Erickson+, 2015)
J/ApJ/775/63 : Gould's Belt VLA Survey. I. Ophiuchus complex (Dzib+, 2013)
J/ApJ/762/128 : Spitzer/IRS disk parameters in Serpens (Oliveira+, 2013)
J/AJ/145/94 : Luminosities of protostars from Spitzer (Dunham+, 2013)
J/MNRAS/421/3257 : MHO catalogue for Serpens and Aquila (Ioannidis+, 2012)
J/ApJ/725/2485 : X-rays from the star-forming complex W40 (Kuhn+, 2010)
J/AJ/140/968 : A cluster of compact radio sources in W40 (Rodriguez+, 2010)
J/AJ/140/266 : NGC 1333 X-ray luminous YSOs properties (Winston+, 2010)
J/ApJ/714/778 : YSOs in the Serpens Molecular Cloud (Oliveira+, 2010)
J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)
J/ApJ/692/973 : Protostars in Perseus, Serpens and Ophiuchus (Enoch+, 2009)
J/ApJ/691/672 : Spectrocopy of YSOs in Serpens MoC (Oliveira+ 2009)
J/ApJ/689/108 : MASIV survey. II. First four epochs (Lovell+, 2008)
J/ApJS/179/249 : Low-luminosity embedded protostar population (Dunham+, 2008)
J/ApJ/669/493 : Spitzer/Chandra YSOs in Serpens cloud core (Winston+, 2007)
J/ApJ/663/1149 : Spitzer survey of Serpens YSO population (Harvey+, 2007)
J/A+A/463/275 : Chandra obs. of Serpens star-forming region (Giardino+, 2007)
J/A+A/458/789 : ISOCAM survey of Serpens/G3-G6 (Djupvik+, 2006)
J/A+A/421/623 : ISOCAM survey of YSOs in Serpens Cloud Core (Kaas+, 2004)
J/A+A/330/990 : VRIJHK phot. of the Serpens cloud core (Giovannetti+ 1998)
J/A+A/308/573 : Ammonia on YSOs IRAS sources (Molinari+ 1996)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Reg Region identification (G1)
5- 23 A19 --- GBS-VLA Radio source name (JHHMMSS.ss+DDMMSS.s)
24 A1 --- f_S4.5 [*] Low flux source (2)
26 A1 --- New [Y/N] New detection? (3)
28 A1 --- l_S4.5 [<] Limit flag on S4.5
30- 34 F5.2 mJy S4.5 [0.03/32.1] 4.5GHz flux density (4)
36- 39 F4.2 mJy e_S4.5 [0.01/5.6]? S4.5 uncertainty (5)
41 A1 --- l_v4.5 [>] Limit flag on v4.5
43- 44 I2 % v4.5 [2/96]? 4.5GHz variability
46- 47 I2 % e_v4.5 [1/35]? v4.5 uncertainty
48 A1 --- f_v4.5 [Ae] v4.5 (6)
50 A1 --- l_S7.5 Limit flag on S7.5
52- 56 F5.2 mJy S7.5 [0.04/11.5]? 7.5GHz flux density (4)
58- 61 F4.2 mJy e_S7.5 [0.02/1.2]? S7.5 uncertainty (5)
63 A1 --- l_v7.5 Limit flag on v7.5
65- 66 I2 % v7.5 [0/97]? 7.5GHz variability
68- 69 I2 % e_v7.5 [5/52]? v7.5 uncertainty
70 A1 --- f_v7.5 [Ae] Flag on v7.5 (6)
72 A1 --- l_alpha Limit fag on alpha
74- 77 F4.1 --- alpha [-4.8/2.1]? Radio spectral index α (7)
79- 81 F3.1 --- e_alpha [0.1/0.7]? alpha uncertainty
83 A1 --- Yc [c] c:Young stellar object candidate based
just on radio properties (column added by
CDS based on Table 5)
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Note (2):
* = The asterisk indicates a source without reported counterparts detected
with an integrated flux <5σ, but with a peak flux ≥5σ.
Note (3):
Y = Source without reported counterparts at any frequency.
N = Source with known counterpart.
Note (4): Flux densities are measured in the combined epoch images.
Note (5): The quoted flux errors comprise the statistical error provided by
IMFIT, the 5% absolute flux uncertainty, and the uncertainty induced by
the pointing error of the VLA primary beam.
Note (6): Flag as follows:
A = Source not detected at three times the noise level on individual epochs,
but detected on the image of the concatenated epochs.
e = Extended
Note (7): An estimation of the radio spectral index α (the flux
density Sν∝να) was obtained for most of the
sources using α=log(Sν(4.5)/Sν(7.5))/log(4.5GHz/7.5GHz),
where Sν(4.5) and Sν(7.5) are the flux densities at 4.5 and
7.5GHz, respectively, and ν is the frequency of the incoming
radiation. See section 3.3 for further explanations.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Reg Region identification (G1)
5- 23 A19 --- GBS-VLA Radio source name (JHHMMSS.ss+DDMMSS.s)
25- 50 A26 --- OName Other name
52- 58 A7 --- XID X-ray name (1)
60 A1 --- SST? [Y ] IR Spitzer detection? (2)
62 A1 --- 2M? [Y ] IR 2MASS detection? (2)
64 A1 --- WISE? [Y ] IR WISE detection? (2)
66- 83 A18 --- Radio Radio name (3)
85-107 A23 --- Type Object type
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Note (1): Abbreviation:
GFM = Giardino et al. (2007, J/A+A/463/275; <[GFM2007] NN> in Simbad)
KGF = Kuhn et al. (2010, J/ApJ/725/2485; <[KGF2010] NNN> in Simbad)
Note (2): Abbreviation:
SST = Evans et al. (2009, J/ApJS/181/321; <[EDJ2009] NNNN> in Simbad),
c2d-GB clouds catalog (Dunham et al. 2013, J/AJ/145/94;
<SSTc2d JHHMMSS.s+DDMMSS> or <SSTgbs JHHMMSSss+DDMMSSs> in Simbad)
2M = Cutri et al. (2003, II/246; <2MASS JHHMMSSss+DDMMSSs> in Simbad)
WISE = Wright et al. (2010AJ....140.1868W 2010AJ....140.1868W, see also II/311,
in Simbad)
Note (3): Abbreviation:
ETC = Eiroa et al. (2005AJ....130..643E 2005AJ....130..643E; <[ETC2005] NN> in Simbad)
NVSS = Condon et al. (1998, VIII/65; in Simbad)
DCE08 = AMI-Consortium et al. (2012MNRAS.420.1019A 2012MNRAS.420.1019A)
RRR = Rodriguez et al. (2010, J/AJ/140/968; <[RRR2010] W40-VLA NN> in Simbad)
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- Reg Region identification (G1)
5- 23 A19 --- GBS-VLA Radio source name (JHHMMSS.SS+DDMMSS.s)
25- 28 A4 --- SpT MK spectral type
30- 38 A9 --- Class SED classification: Class I, II, III, Flat (YSO),
HAeBe=Herbig AeBe star, P-HAeBe=proto-HAeBe
39 A1 --- f_Class [d] HAeBe candidate (1)
41 A1 --- Var? [YNE] High variability (2)
43 A1 --- alph? [PFN] Positive, Flat, or Negative index (3)
45 A1 --- X? [YN] X-ray flux reported in literature?
47- 49 A3 --- r_Class Class reference(s) (4)
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Note (1): This source has a mass of ∼4M☉ and no Ks-band excess. We
therefore consider it as an HAeBe candidate.
Note (2): Flag as follows:
Y = flux variability ≳50% at a 3σ level in at least one frequency
N = variability is <50% at both frequencies
E = Extended
Note (3): Spectral index α as follows:
P = higher than 0.2
F = flat; between -0.2 and +0.2
N = lower than -0.2
Note (4): References as follows:
1 = Giardino et al. (2007, J/A+A/463/275),
2 = Enoch et al. (2009, J/ApJ/692/973),
3 = Kuhn et al. (2010, J/ApJ/725/2485),
4 = Shuping et al. (2012AJ....144..116S 2012AJ....144..116S),
5 = Winston et al. (2010, J/AJ/140/266),
6 = Preibisch (1999A&A...345..583P 1999A&A...345..583P),
7 = c2d-GB cloud catalog (Dunham et al. 2013, J/AJ/145/94).
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Global notes:
Note (G1): Code as follows:
S = Detected sources in the Serpens molecular cloud
W40 = Detected sources in the W40 region
Ss = Detected sources in the Serpens South cluster
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History:
From electronic version of the journal
References:
Dzib et al. Paper I. 2013ApJ...775...63D 2013ApJ...775...63D Cat. J/ApJ/775/63
Kounkel et al. Paper III. 2014ApJ...790...49K 2014ApJ...790...49K Cat. J/ApJ/790/49
Dzib et al. Paper IV. 2015ApJ...801...91D 2015ApJ...801...91D Cat. J/ApJ/801/91
Pech et al. Paper V. 2016ApJ...818..116P 2016ApJ...818..116P
(End) Emmanuelle Perret [CDS] 18-Sep-2015