J/ApJ/860/174 CO in Protostars (COPS): Herschel spectroscopy (Yang+, 2018)
CO in Protostars (COPS): Herschel-SPIRE spectroscopy of embedded protostars.
Yang Y.-L., Green J.D., Evans II N.J., Lee J.-E., Jorgensen J.K.,
Kristensen L.E., Mottram J.C., Herczeg G., Karska A., Dionatos O.,
Bergin E.A., Bouwman J., van Dishoeck E.F., van Kempen T.A., Larson R.L.,
Yildiz U.A.
<Astrophys. J., 860, 174 (2018)>
=2018ApJ...860..174Y 2018ApJ...860..174Y
ADC_Keywords: YSOs; Interstellar medium; Spectra, millimetric/submm;
Surveys; Carbon monoxide
Keywords: ISM: molecules; stars: protostars; submillimeter: ISM;
submillimeter: stars; surveys
Abstract:
We present full spectral scans from 200 to 670µm of 26 Class 0+I
protostellar sources obtained with Herschel-SPIRE as part of the
"COPS-SPIRE" Open Time program, complementary to the DIGIT and WISH
Key Programs. Based on our nearly continuous, line-free spectra from
200 to 670µm, the calculated bolometric luminosities (Lbol)
increase by 50% on average, and the bolometric temperatures (Tbol)
decrease by 10% on average, in comparison with the measurements
without Herschel. Fifteen protostars have the same class using Tbol
and Lbol/Lsmm. We identify rotational transitions of CO lines from
J=4->3 to J=13->12, along with emission lines of 13CO, HCO+,
H2O, and [CI]. The ratios of 12CO to 13CO indicate that 12CO
emission remains optically thick for Jup<13. We fit up to four
components of temperature from the rotational diagram with flexible
break points to separate the components. The distribution of
rotational temperatures shows a primary population around 100K with a
secondary population at ∼350K. We quantify the correlations of each
line pair found in our data set and find that the strength of the
correlation of CO lines decreases as the difference between J levels
between two CO lines increases. The multiple origins of CO emission
previously revealed by velocity-resolved profiles are consistent with
this smooth distribution if each physical component contributes to a
wide range of CO lines with significant overlap in the CO ladder. We
investigate the spatial extent of CO emission and find that the
morphology is more centrally peaked and less bipolar at high-J lines.
We find the CO emission observed with SPIRE related to outflows, which
consists of two components, the entrained gas and shocked gas, as
revealed by our rotational diagram analysis, as well as the studies
with velocity-resolved CO emission.
Description:
Our sample of 27 COPS protostars contains 20 sources overlapping with
the Dust, Gas, and Ice In Time (DIGIT; PI: N. Evans;
Fedele+ 2013A&A...559A..77F 2013A&A...559A..77F ; Green+ 2013ApJ...770..123G 2013ApJ...770..123G ;
Meeus+ 2013A&A...559A..84M 2013A&A...559A..84M and Lee+ 2014ApJS..214...21L 2014ApJS..214...21L) and 17
overlapping with the Water in Star-forming Regions with Herschel (WISH;
PI: E. van Dishoeck; van Dishoeck+ 2011PASP..123..138V 2011PASP..123..138V ; see also
Nisini+ 2010A&A...518L.120N 2010A&A...518L.120N ; Kristensen+ 2012A&A...542A...8K 2012A&A...542A...8K ;
Karska+ 2013A&A...552A.141K 2013A&A...552A.141K ; San Jose-Garcia+ 2013A&A...553A.125S 2013A&A...553A.125S ;
Wampfler+ 2013A&A...552A..56W 2013A&A...552A..56W and Yildiz+ 2013A&A...556A..89Y 2013A&A...556A..89Y)
Herschel Key Programs.
The SPIRE Fourier Transform Spectrometer (FTS) data were taken in a
single pointing with sparse image sampling in 1hr of integration time
per source. The spectra were taken with the high-resolution (HR) mode
and are divided into two orders covering the spectral ranges of
194-325um (spectrograph short wavelengths (SSW)) and 320-690um
(spectrograph long wavelengths (SLW)).
We also collect and reduce PACS spectroscopy and photometry data from
the COPS-DIGIT-FOOSH (CDF) archive (see Green+, 2016, J/AJ/151/75) for
comparison.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 81 27 Source list
table2.dat 74 27 Observing log
table3.dat 75 26 Evolutionary indicators
table5.dat 223 138374 Line fitting results
table10.dat 217 26 ObsID of photometry
table12.dat 52 440 References for photometry
fig17.dat 55 90950 SPIRE 1D spectra for the COPS sources
refs.dat 74 92 References (table added by CDS)
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See also:
II/197 : ISM towards IC 348 and Per OB2 (Cernis, 1993)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/332 : c2d Spitzer final data release (DR4) (Evans+, 2003)
II/311 : WISE All-Sky Data Release (Cutri+ 2012)
J/AJ/117/354 : OB associations from Hipparcos (de Zeeuw+, 1999)
J/BaltA/12/301 : Vilnius photometry in Barnard 1 (Cernis+, 2003)
J/MNRAS/355/1272 : BVIJHKs photometry around CG 12 (Maheswar+, 2004)
J/A+A/432/369 : Leiden Atomic & Molecular Database (LAMDA) (Schoeier+, 2005)
J/ApJ/638/293 : 1.1mm sources in the Perseus Molecular Cloud (Enoch+, 2006)
J/A+A/447/609 : 1.2mm continuum obs. in rho Oph cloud (Stanke+, 2006)
J/A+A/470/281 : WFI optical photometry in Cha II dark cloud (Spezzi+, 2007)
J/AJ/133/1560 : Spitzer c2d small clouds and cores (Wu+, 2007)
J/ApJS/175/277 : Submm-Continuum SCUBA detections (Di Francesco+, 2008)
J/ApJ/684/1240 : Prestellar cores in Perseus, Serpens & Oph. (Enoch+, 2008)
J/ApJ/683/822 : Star formation in Ophiuchus & Perseus II. (Jorgensen+, 2008)
J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)
J/ApJS/184/18 : Spitzer survey of young stellar clusters (Gutermuth+, 2009)
J/ApJS/185/198 : The Cepheus flare observed with IRAC and MIPS (Kirk+, 2009)
J/A+A/507/1425 : APEX-CHAMP+. II. (Van Kempen+, 2009)
J/A+A/498/167 : Embedded sources in L 1688 (van Kempen+, 2009)
J/MNRAS/406/1745 : H2O in interstellar shock waves (Flower+, 2010)
J/ApJS/186/259 : Taurus Spitzer survey: new candidate members (Rebull+, 2010)
J/ApJS/194/43 : YSOs candidates and knots in CrA cloud (Peterson+, 2011)
J/AJ/145/94 : Luminosities of protostars from Spitzer (Dunham+, 2013)
J/A+A/572/A21 : H2O spectra of nearby Class 0/I protostars (Mottram+, 2014)
J/A+A/568/A125 : NGC 1333 IRAS 4A H2O observations (Santangelo+, 2014)
J/ApJS/220/11 : SEDs of Spitzer YSOs in the Gould Belt (Dunham+, 2015)
J/AJ/150/175 : YSOVAR: infrared photometry in NGC 1333 (Rebull+, 2015)
J/A+A/576/A109 : YSOs APEX-CHAMP+ high-J CO maps (Yildiz+, 2015)
J/AJ/151/75 : Herschel-PACS & -SPIRE spectroscopy (Green+, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Protostellar source name
17- 21 A5 --- Cloud Cloud
23- 25 I3 pc Dist [106/450] Distance
27- 28 I2 h RAh Hour of right ascension (J2000)
30- 31 I2 min RAm Minute of right ascension (J2000)
33- 36 F4.1 s RAs Second of right ascension (J2000)
38 A1 --- DE- Sign of declination (J2000)
39- 40 I2 deg DEd Degree of declination (J2000)
42- 43 I2 arcmin DEm Arcminute of declination (J2000)
45- 48 F4.1 arcsec DEs Arcsecond of declination (J2000)
50- 52 A3 --- Survey Survey overlap with DIGIT (D) and WISH (W)
54- 59 A6 --- Ref References (see refs.dat file)
61- 70 A10 --- RefDist Distance reference(s) (see refs.dat file)
72- 81 A10 --- ID Internal identifier as in Tables 5, 12 and
fig17; column added by CDS
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Protostellar source name
17- 31 A15 --- OName Other name
33- 42 I10 --- ObsId [1342242620/1342254037] Herschel ObsID
44- 54 A11 "Y/M/D" Date Observation date (UT)
56- 59 F4.1 arcsec Ap [21.8/51.8]? PACS 1D aperture (1)
60 A1 --- f_Ap A: all 25 PACS spaxels are used for
extracting the 1D spectrum
62- 74 A13 --- Notes Notes
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Note (1): Blanks indicate that no PACS 1D spectrum is extracted.
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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- 15 A15 --- Name Protostellar source name
17 A1 --- f_Name Flag on Name (2)
19- 23 F5.2 Lsun Lbol [0.3/35.1] Bolometric luminosity
25- 29 F5.3 Lsun Lsmm [0.01/0.2] Bolometric luminosity of
the spectrum >350um
31- 36 F6.4 Lsun LCO ? CO luminosity
37 A1 --- f_LCO c: No CO line is detected toward L1014
39- 43 F5.1 K Tbol [33.2/592] Bolometric temperature
45- 49 F5.2 --- aNIR [-0.2/3.1] αNIR value (3)
51- 54 F4.2 --- e_aNIR [0.03/1.5] aNIR uncertainty
56- 59 A4 --- ClNIR Class according to αNIR
61 A1 --- Clsmm Class according to the Lbol/Lsmm criterion
63- 68 A6 --- ClTbol Class according to Tbol
70 A1 --- f_ClTbol Flag on ClTbol (2)
72- 75 A4 --- Ref2 References (see refs.dat file)
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Note (2): Flag as follows:
b = The Lbol, Tbol, and Lsmm are collected
from Lindberg+ (2014A&A...565A..29L 2014A&A...565A..29L). Other quantities are calculated
from the SEDs with the COPS spectra and data from the CDF archive,
which have obvious source contaminations.
a = The sources have Tbol close to the criteria dividing between Class I and
flat spectrum.
Note (3): The αNIR is recalculated with photometric fluxes collected
from the literature. If the photometric fluxes are not found, we use
the spectrophotometric fluxes extracted from the Spitzer-IRS spectra.
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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- 10 A10 --- ID Object identifier
12- 28 A17 --- Line Line identifier
30- 38 F9.5 um LabWL [55.1/650.3] Theoretical line centroid
wavelength
40- 48 F9.5 um ObsWL [55/652.9] Fitted line centroid wavelength
50- 61 F12.5 um e_ObsWL [0.0001/132955]? Uncertainty in ObsWL
62 A1 --- feObsWL Flag on e_ObsWL (1)
64- 76 E13.6 W/cm2 Str [-8.7e-16/3.3e-16] Fitted line strength
78- 90 E13.6 W/cm2 e_Str [3.8e-26/0.7]? Uncertainty in Str
91 A1 --- feStr Flag on e_Str (1)
93- 99 F7.5 um FWHM [0.02/4] Fitted full width at half-maximum
101-110 F10.5 um e_FWHM [0/24]? Uncertainty in FWHM
111 A1 --- feFWHM Flag on e_FWHM (1)
113-125 E13.6 W/cm2/um Base [-1.7e-19/5.9e-17] Fitted baseline intensity
127-138 E12.6 W/cm2/um Noise [3.9e-26/9.8e-19] Residual intensity
140-151 E12.6 --- S/N [0/756498] Signal-to-Noise ratio
153-160 F8.3 K Eu [23.6/6195.6] Upper energy level (2)
162-173 E12.6 s-1 A [0/2.5] Einstein-A value (2)
175-176 I2 --- g [1/95] Multiplicity of upper energy level (2)
178-188 F11.7 deg RAdeg Right Ascension in decimal degrees (J2000)
190-200 F11.7 deg DEdeg Declination in decimal degrees (J2000)
202-206 A5 --- PixNum Pixel label (3)
208-221 A14 --- Blend Blending flag (4)
223 I1 --- Val [0/1] Validity flag (5)
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Note (1): Flag as follows:
n = fitting result that is not well-constrained.
f = uncertainties cannot be generated because some parameters are fixed
during the line fitting.
Note (2): From LAMDA, Leiden Atomic and Molecular Database
(Schoier+ 2005, J/A+A/432/369).
Note (3): "c" for the 1-D spectrum measurements and the specific pixel
number/name for individual spaxels.
Note (4): Flag which highlights any other line within one resolution element
to the fitted line centroid.
Note (5): Flag which determines the overall certainty of the fitting
for a given line. Set to zero when the fitting result is not
well-constrained.
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Byte-by-byte Description of file: table10.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Protostellar source name
17-182 A166 --- PACS Herschel PACS obsIDs
184-217 A34 --- SPIRE Herschel SPIRE obsIDs
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Byte-by-byte Description of file: table12.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- ID Object identifier
12- 17 F6.1 um lambda [0.4/3000] Wavelength
19- 30 E12.6 Jy Flux [8.1e-6/1150] Flux density at lambda
32- 43 E12.6 Jy e_Flux [2e-6/2000]? Uncertainty in Flux
45- 52 A8 --- Ref Photometry reference code (see refs.dat file)
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Byte-by-byte Description of file: fig17.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- ID Object identifier
12- 18 F7.3 um lambda [195/671] Wavelength
20- 29 F10.6 Jy Flux [0.9/946.2] Absolute corrected flux density
31- 42 E12.5 Jy Flat [-20.6/409] Continuum-subtracted corrected
flux density
44- 55 E12.5 Jy Res [-20.6/22] Residual after removal of continuum
and lines
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Ref Reference code
9- 27 A19 --- BibCode Bibcode of the reference
29- 57 A29 --- Auth First author's name(s)
59- 74 A16 --- Comm Comment
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 09-Jul-2019