J/ApJ/692/973 Protostars in Perseus, Serpens and Ophiuchus (Enoch+, 2009)
Properties of the youngest protostars in Perseus, Serpens, and Ophiuchus.
Enoch M.L., Evans N.J., Sargent A.I., Glenn J.
<Astrophys. J., 692, 973-997 (2009)>
=2009ApJ...692..973E 2009ApJ...692..973E
ADC_Keywords: YSOs ; Infrared sources ; Cross identifications ;
Millimetric/submm sources ; Molecular clouds
Keywords: infrared: ISM - ISM: clouds - ISM: individual (Perseus, Serpens,
Ophiuchus) - stars: formation - submillimeter
Abstract:
We present an unbiased census of deeply embedded protostars in
Perseus, Serpens, and Ophiuchus, assembled by combining large-scale
1.1mm Bolocam continuum and Spitzer Legacy surveys. We identify
protostellar candidates based on their mid-infrared (mid-IR)
properties, correlate their positions with 1.1mm core positions from
Enoch et al. in 2006 (Cat. J/ApJ/638/293) and 2007ApJ...666..982E 2007ApJ...666..982E, and
Young et al. in 2006ApJ...644..326Y 2006ApJ...644..326Y, and construct well-sampled
spectral energy distributions using our extensive wavelength coverage
(λ=1.25-1100um). Source classification based on the bolometric
temperature yields a total of 39 Class 0 and 89 Class I sources in the
three-cloud sample. We compare to protostellar evolutionary models
using the bolometric temperature-luminosity diagram, finding a
population of low-luminosity Class I sources that are inconsistent
with constant or monotonically decreasing mass accretion rates.
Description:
Utilizing large-scale 1.1mm surveys (Enoch et al. 2006, Cat.
J/ApJ/638/293, 2007ApJ...666..982E 2007ApJ...666..982E; Young et al. 2006ApJ...644..326Y 2006ApJ...644..326Y)
together with Spitzer IRAC and MIPS maps from the c2d Legacy program
(Evans et al. 2003PASP..115..965E 2003PASP..115..965E), we have constructed an unbiased
census of deeply embedded protostars in the Perseus, Serpens, and
Ophiuchus molecular clouds. Our sample includes a total of 39 Class 0
sources and 89 Class I sources.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 102 66 Bolometric temperatures, luminosities, and
envelope masses of embedded protostars in Perseus
table3.dat 101 34 Bolometric temperatures, luminosities, and
envelope masses of cold protostars in Serpens
table4.dat 102 28 Bolometric temperatures, luminosities, and
envelope masses of cold protostars in Ophiuchus
table5.dat 96 18 Class II sources detected at 1.1mm in Perseus,
Serpens, and Ophiuchus
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See also:
J/ApJ/638/293 : 1.1mm sources in the Perseus Molecular Cloud (Enoch+, 2006)
J/A+A/447/609 : 1.2mm continuum observations in rho Oph cloud (Stanke+, 2006)
J/ApJ/663/1149 : Spitzer survey of Serpens YSO population (Harvey+, 2007)
J/ApJ/669/493 : Spitzer/Chandra YSOs in Serpens cloud core (Winston+, 2007)
Byte-by-byte Description of file: table2.dat table3.dat table4.dat
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Bytes Format Units Label Explanations
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1 A1 --- cl [0/I] Source class
3- 5 A3 --- Cloud Cloud name (Per=Perseus, Ser=Serpens,
Oph=Ophiuchus)
6- 9 A4 --- --- [emb-]
11- 12 I2 --- ID Embedded protostar identification
13- 15 A3 --- f_ID [c-h, ] Flag on ID (1)
17- 35 A19 --- c2d SSTc2d identification (JHHMMSS.ss+DDMMSS.s)
37- 39 I3 K Tbol Bolometric temperature
41- 43 I3 K e_Tbol Tbol uncertainty (2)
45- 49 F5.2 Lsun Lbol Bolometric luminosity
51- 54 F4.2 Lsun e_Lbol Lbol uncertainty (2)
56- 60 F5.2 --- alpha IR spectral index
62- 65 F4.2 --- e_alpha alpha uncertainty
67- 70 F4.2 Msun Menv Envelope Mass (3)
72- 75 F4.2 Msun e_Menv Menv uncertainty (4)
77- 80 A4 --- --- [Bolo]
82- 84 I3 --- Bolo [1/122]? Bolocam identification (5)
85 A1 --- f_Bolo [ab] Several associations (6)
87-102 A16 --- OName Other names
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Note (1): Flags as follows:
c = Saturated 24um flux has been replaced with IRAS 25um flux for the
calculation of Lbol and Tbol.
d = Saturated at either 24um or 70um so Lbol is likely an underestimate,
but the IRAS beam is too confused to measure reliable 25um or 60um
fluxes.
e = Source lies outside the 70um map.
f = Missing 70um flux has been replaced with IRAS 60um flux for the
calculation of Lbol and Tbol.
g = Oph-emb 2 is saturated at 160um; when the 100um IRAS flux is included
the resulting Lbol is 16±6L☉, consistent with the luminosity
calculated by Walker et al. (1986ApJ...309L..47W 1986ApJ...309L..47W) when scaled to a
distance of 125pc.
h = Saturated 70um flux has been replaced with IRAS 60um flux for the
calculation of Lbol and Tbol.
Note (2): Uncertainties for Tbol and Lbol are taken to be the difference
of values calculated by the midpoint and prismoidal methods (see the
Appendix for further details).
Note (3): The envelope mass Menv is calculated from the 1.1mm flux assuming
a dust temperature of TD=15K.
Note (4): Uncertainties in Menv are from the photometric errors in the
total flux only. Absolute uncertainties in the mass may be a factor
of 2 or more, from uncertainties in d, κ1mm, and TD, but
relative values should be much more accurate.
Note (5): Bolocam IDs are from Papers I-III, and indicate that the
protostellar source is within 1.0 core FWHM of a given Bolocam core.
Per-Bolo are <[EYG2006] Bolo NNN>, Ser-Bolo are <[EGE2007] Bolo NN>,
and Oph-Bolo are <[YEE2006] NN> in Simbad. If no ID is listed, the
source was not originally identified as a distinct 1.1mm core, but
there is detectable (≳3σ) 1.1mm emission at the position of
the source.
Note (6): Flags as follows:
a = More than one protostar is associated with this Bolocam core or
source is in a crowded region; mass is based on flux measured in
a 30"-40" diameter aperture.
b = More than one protostar is associated with this Bolocam core;
mass is based on dividing Bolocam core flux equally (source
separation is less than 30").
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Cloud Cloud designation
5- 23 A19 --- c2d SSTc2d identification (JHHMMSS.ss+DDMMSS.s)
25- 28 I4 K Tbol Bolometric temperature
30- 32 I3 K e_Tbol Tbol uncertainty
34- 37 F4.2 Lsun Lbol Bolometric luminosity
39- 42 F4.2 Lsun e_Lbol Lbol uncertainty
44- 48 F5.2 --- alpha IR spectral index
50- 53 F4.2 --- e_alpha alpha uncertainty
55- 58 F4.2 Msun M1mm 1mm mass (1)
60- 63 F4.2 Msun e_M1mm M1mm uncertainty
65- 72 A8 --- --- [BoloOphSPer-]
74- 76 I3 --- Bolo [1/122]? Bolocam identification
77 A1 --- f_Bolo [*] Confused map (2)
79- 93 A15 --- OName Other names
94 A1 --- n_OName [c] Notes on the source (3)
96 I1 --- r_OName ? Reference (4)
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Note (1): The 1.1mm mass (M1mm) is calculated for an optically thin disk
and a dust temperature of TD=15K. Our assumption for the dust opacity
may be incorrect for typical Class II disks, however, where grain
growth is a possibility (e.g., Natta et al. 2007prpl.conf..767N).
Note (2): The source is in a confused region at 1.1mm, and the association
of the Spitzer object with the given 1.1mm emission is not secure.
Note (3): Typically classified as a Class I source, RNO 15 has a bolometric
temperature just above the Class I cutoff in our sample. The spectral
index of RNO 15 is αIR=-0.09, placing it in the "flat spectrum"
category, or close to the Class I boundary.
Note (4): References as follows:
1 = Cohen 1980AJ.....85...29C 1980AJ.....85...29C;
2 = Herbig & Kameswara 1972ApJ...174..401H 1972ApJ...174..401H;
3 = Aspin et al. 1994, Cat. J/A+AS/106/165;
4 = Cohen & Kuhi 1979ApJS...41..743C 1979ApJS...41..743C;
5 = Greene & Young 1992ApJ...395..516G 1992ApJ...395..516G.
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Nomenclature notes:
Protostars are <[EES2009] Cloud ID> in Simbad.
History:
From electronic version of the journal
References:
Enoch et al. Paper I. 2006ApJ...638..293E 2006ApJ...638..293E Cat. J/ApJ/638/293
Young et al. Paper II. 2006ApJ...644..326Y 2006ApJ...644..326Y
Enoch et al. Paper III. 2007ApJ...666..982E 2007ApJ...666..982E
(End) Emmanuelle Perret [CDS] 04-Mar-2011