J/A+A/498/167 Embedded sources in L 1688 (van Kempen+, 2009)
The nature of the class I population in Ophiuchus as revealed through gas and
dust mapping.
van Kempen T.A., van Dishoeck E.F., Salter D.M., Hogerheijde M.R.,
Jorgensen J.K., Boogert A.C.A.
<Astron. Astrophys., 498, 167-194 (2009)>
=2009A&A...498..167V 2009A&A...498..167V
ADC_Keywords: Molecular clouds ; Millimetric/submm sources
Keywords: astrochemistry - circumstellar matter - stars: formation -
submillimeter - ISM: clouds - ISM: molecules
Abstract:
The Ophiuchus clouds, in particular L 1688, are an excellent region to
study the embedded phases of star formation, due to the relatively
large number of protostars. However, the standard method of finding
and characterizing embedded young stellar objects (YSOs) through just
their infrared spectral slope does not yield a reliable sample. This
may affect the age determinations, often derived from the statistics
on the total number of embedded YSOs and pre-main sequence stars
within a cloud.
Our aim is to characterize the structure of protostellar envelopes on
an individual basis and to correctly identify the embedded YSO
population of L 1688.
Description:
Spectral maps of the HCO+ J=4-3 and C18O J=3-2 lines, using the
HARP-B array on the James Clerk Maxwell Telescope and SCUBA 850um dust
maps, are obtained of all sources in the L 1688 region with infrared
spectral slopes consistent with, or close to, that of embedded YSOs.
Selected 350um maps obtained with the Caltech Submillimeter
Observatory are presented as well. The properties, extent and
variation of dense gas, column density and dust up to 1' (∼7500AU) are
probed at 15" resolution. Using the spatial variation of the gas and
dust, together with the intensity of the HCO+ J=4-3 line, we are
able to accurately identify the truly embedded YSOs and determine
their properties.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 80 45 Sample of embedded sources in L 1688, with
additional known disks included
table4.dat 118 45 Source fluxes including IRAC 1-4, MIPS 1-2,
SHARC-II, SCUBA and 1.3mm data
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See also:
II/289 : JKH photometry in LDN 1688 (Wilking+, 2008)
J/A+A/372/173 : ISOCAM observations of rho Ophiuchi cloud (Bontemps+, 2001)
J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)
J/ApJ/671/1800 : rho Oph SCUBA observations (Andrews+, 2007)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 A1 --- n_Source [D] D for known disks
3- 20 A18 --- Source Source name
23- 47 A25 --- ONames Other names
49- 50 I2 h RAh Right ascension (J2000)
52- 53 I2 min RAm Right ascension (J2000)
55- 58 F4.1 s RAs Right ascension (J2000)
60 A1 --- DE- Declination sign (J2000)
61- 62 I2 deg DEd Declination (J2000)
64- 65 I2 arcmin DEm Declination (J2000)
67- 70 F4.1 arcsec DEs Declination (J2000)
72 I1 --- r_Pos [1/2] Reference for position (1)
74- 78 F5.2 --- alpha ? Spectral index between 2 and 24µm (2)
79- 80 A2 --- n_alpha [no ] no when no spectral index
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Note (1): Reference for position as follows:
1 = Bontemps et al., 2001, Cat. J/A+A/372/173
2 = c2d delivery document
Note (2): From Evans et al., 2009, Cat. J/ApJS/181/321. See also Sect. 5.5.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1 A1 --- n_Source [D] D for known disks
3- 20 A18 --- Source Source name
22- 28 E7.3 mJy S3.6 ?=- IRAC 3.6µm flux density
29- 30 A2 --- n_S3.6 [K*d ] Note on S3.6 (1)
32- 38 E7.3 mJy S4.5 ?=- IRAC 4.5µm flux density
39 A1 --- n_S4.5 [K*] Note on S4.5 (1)
41- 47 E7.3 mJy S5.8 IRAC 5.8µm flux density
48 A1 --- n_S5.8 [K*] Note on S5.8 (1)
50- 56 E7.3 mJy S8.0 ?=- IRAC 8.0µm flux density
57 A1 --- n_S8.0 [*] Note on S8.0 (1)
59- 65 E7.3 mJy S24 ?=- MIPS 24µm flux density
66 A1 --- n_S24 [*] Note on S24 (1)
68 A1 --- l_S70 Limit flag on S70
69- 75 E7.3 mJy S70 ?=- MIPS (∼10") 70µm flux density
77- 82 E6.2 mJy S350 ?=- SHARC (9-25") 350µm flux density
83 A1 --- n_S350 [abc] Note on S350 (1)
85 A1 --- l_S450 Limit flag on S450
86- 91 E6.2 mJy S450 ?=- SCUBA (10") 450µm flux density
92 A1 --- n_S450 [c] Note on S450 (1)
94 A1 --- l_S850 Limit flag on S850
95-100 E6.2 mJy S850 ?=- SCUBA (15") 850µm flux density
101 A1 --- n_S850 [b] Note on S850 (1)
103 A1 --- l_S850-2 Limit flag on S850-2
104-109 E6.2 mJy S850-2 ? SCUBA (25") 850µm flux density
111 A1 --- l_S1300 Limit flag on S1330
112-117 E6.2 mJy S1300 ?=- (15") 1300µm flux density
118 A1 --- n_S1300 [)] Uncertainty flag on S1300um
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Note (1): Notes as follows:
a = This paper;
b = 350/450um flux taken from Andrews & Williams (2007, Cat.
J/ApJ/671/1800). Fluxes obtained with SHARC-II are given either
in a 9" beam (Andrews & Williams, 2007, Cat. J/ApJ/671/1800) or
in a 25" radius (This work)
c = data taken from Andre et al. (1993ApJ...406..122A 1993ApJ...406..122A)
d = two sources within 4" with a total flux of 2E+2mJy
* = band-filled sources with a S/N<5 or sources with S/N<5. Such
limits are caused either by saturation or a very low emission.
K = added to the flux indicates that the obtained flux was flagged
as "Complex", with multiple detection within 2-3"
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History:
* 01-Feb-2010: From electronic version of the journal
* 15-Jul-2010: position corrected for SSTc2d J162748.2-244225 in table 1.
(End) Patricia Vannier [CDS] 01-Feb-2010