J/A+A/615/A125 Molecular cloud in Corona Australis (Bresnahan+, 2018)
The dense cores and filamentary structure of the molecular cloud in Corona
Australis:
Herschel SPIRE and PACS observations from the Herschel Gould Belt Survey.
Bresnahan D., Ward-Thompson D., Kirk J.M., Pattle K., Eyres S.,
White G.J., Koenyves V., A.Men'shchikov, Andre Ph., Schneider N.,
Di Francesco J., Arzoumanian D., Benedettini M., Ladjelate B.,
Palmeirim P., Bracco A., Molinari S., Pezzuto S., Spinoglio L.
<Astron. Astrophys. 615, A125 (2018)>
=2018A&A...615A.125B 2018A&A...615A.125B (SIMBAD/NED BibCode)
ADC_Keywords: Molecular clouds ; Photometry, millimetric/submm
Keywords: stars: formation - ISM: clouds - ISM: structure -
ISM: individual objects: Corona Australis molecular cloud -
submillimeter: ISM
Abstract:
We present a catalogue of prestellar and starless cores within the
Corona Australis molecular cloud using photometric data from the
Herschel Space Observatory. At a distance of d∼130pc, Corona
Australis is one of the closest star-forming regions. Herschel has
taken multi-wavelength data of Corona Australis with both the Spectral
and Photometric Imaging Receiver (SPIRE; Griffin et al.
2010A&A...518L...3G 2010A&A...518L...3G) and the Photodetector Array Camera and
Spectrometer (PACS; Poglitsch et al. 2010A&A...518L...2P 2010A&A...518L...2P) photometric
cameras in a parallel mode with wavelengths in the range 70um to
500um. A complete sample of starless and prestellar cores and embedded
protostars is identified. Other results from the Herschel Gould Belt
Survey have shown spatial correlation between the distribution of
dense cores and the filamentary structure within the molecular clouds.
We go further and show correlations between the properties of these
cores and their spatial distribution within the clouds, with a
particular focus on the mass distribution of the dense cores with
respect to their filamentary proximity. We find that only lower-mass
starless cores form away from filaments, while all of the higher-mass
prestellar cores form in close proximity to or directly on the
filamentary structure. This result supports the paradigm that
prestellar cores mostly form on filaments. We analyse the mass
distribution across the molecular cloud, finding evidence that the
region around the Coronet appears to be at a more dynamically advanced
evolutionary stage in comparison to the rest of the clumps within the
cloud.
Description:
Based on Herschel Gould Belt survey (Andre et al.,
2010A&A...518L.102A 2010A&A...518L.102A) observations of the Corona Australis molecular
cloud, and using the multi-scale, multi-wavelength source extraction
algorithm getsources (Men'shchikov et al., 2012A&A...542A..81M 2012A&A...542A..81M), we
identified a total of 177 dense cores, including 163 starless cores
and 14 protostellar cores. We include 62 additional low-mass objects.
The observed properties of all dense cores are given in tablea1.dat,
and their derived properties are listed in tablea2.dat.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 603 239 Observed properties of dense cores in
Corona Australis
tablea2.dat 211 239 Derived properties of dense cores in
Corona Australis
list.dat 95 2 List of fits images
fits/* . 2 Individual fits files
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See also:
http://gouldbelt-herschel.cea.fr/ : Herschel Gould Belt Home Page
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq [1/239] Core running number
5- 19 A15 --- Name Core name, HHMMSS.s+DDMMSS, to be added
after HGBS_J
21- 22 I2 h RAh Right ascension (J2000)
24- 25 I2 min RAm Right ascension (J2000)
27- 31 F5.2 s RAs Right ascension (J2000)
33 A1 --- DE- Declination sign (J2000)
34- 35 I2 deg DEd Declination (J2000)
37- 38 I2 arcmin DEm Declination (J2000)
40- 43 F4.1 arcsec DEs Declination (J2000)
45- 48 I4 --- Signi070 Detection significance at 70um
50- 58 E9.2 Jy/beam Sp070 Peak flux density at 70um
60- 68 E9.2 Jy/beam e_Sp070 Error on peak flux density at 70um
70- 78 F9.2 --- Sp/Sbg070 Contrast over local background at 70um
80- 88 E9.2 Jy/beam Sconv070 Smoothed peak flux density at 70um
(in Jy/beam500)
90- 98 E9.2 Jy Stot070 Integrated flux density at 70um
100-108 E9.2 Jy e_Stot070 [] Error on integrated flux density at 70um
110-112 I3 arcsec FWHMa070 ?=0 Major FWHM diameter at 70um
114-116 I3 arcsec FWHMb070 ?=0 Minor FWHM diameter at 70um
118-120 I3 deg PA070 ?=0 Position angle at 70um
122-125 I4 --- Signi160 Detection significance at 160um
127-135 E9.2 Jy/beam Sp160 Peak flux density at 160um
137-145 E9.2 Jy/beam e_Sp160 Error on peak flux density at 160um
147-155 F9.2 --- Sp/Sbg160 Contrast over local background at 160um
157-165 E9.2 Jy/beam Sconv160 Smoothed peak flux density at 160um
(in Jy/beam500)
167-175 E9.2 Jy Stot160 Integrated flux density at 160um
177-185 E9.2 Jy e_Stot160 [] Error on integrated flux density at 160um
187-189 I3 arcsec FWHMa160 ?=0 Major FWHM diameter at 160um
191-193 I3 arcsec FWHMb160 ?=0 Minor FWHM diameter at 160um
195-197 I3 deg PA160 ?=0 Position angle at 160um
199-202 I4 --- Signi250 Detection significance at 250um
204-212 E9.2 Jy/beam Sp250 Peak flux density at 250um
214-221 E8.2 Jy/beam e_Sp250 Error on peak flux density at 250um
223-229 F7.2 --- Sp/Sbg250 Contrast over local background at 250um
231-239 E9.2 Jy/beam Sconv250 Smoothed peak flux density at 250um
(in Jy/beam500)
241-249 E9.2 Jy Stot250 Integrated flux density at 250um
251-259 E9.2 Jy e_Stot250 Error on integrated flux density at 250um
261-263 I3 arcsec FWHMa250 ?=0 Major FWHM diameter at 250um
265-267 I3 arcsec FWHMb250 ?=0 Minor FWHM diameter at 250um
269-271 I3 deg PA250 ?=0 Position angle at 250um
273-276 I4 --- Signi350 Detection significance at 350um
278-286 E9.2 Jy/beam Sp350 Peak flux density at 350um
288-296 E9.2 Jy/beam e_Sp350 Error on peak flux density at 350um
298-304 F7.2 --- Sp/Sbg350 Contrast over local background at 350um
306-314 E9.2 Jy/beam Sconv350 Smoothed peak flux density at 350um
(in Jy/beam500)
316-324 E9.2 Jy Stot350 Integrated flux density at 350um
326-334 E9.2 Jy e_Stot350 [] Error on integrated flux density at 350um
336-338 I3 arcsec FWHMa350 Major FWHM diameter of core at 350um
340-342 I3 arcsec FWHMb350 Minor FWHM diameter of core at 350um
344-346 I3 deg PA350 Position angle of core at 350um
348-351 I4 --- Signi500 ?=-999 Detection significance at 500um
353-361 E9.3 Jy/beam Sp500 Peak flux density at 500um
363-370 E8.2 Jy/beam e_Sp500 Error on peak flux density at 500um
372-377 F6.2 --- Sp/Sbg500 Contrast over local background at 500um
379-387 E9.2 Jy Stot500 Integrated flux density at 500um
389-397 E9.2 Jy e_Stot500 Error on integrated flux density at 500um
399-401 I3 arcsec FWHMa500 Major FWHM diameter of core at 500um
403-404 I2 arcsec FWHMb500 Minor FWHM diameter of core at 500um
406-408 I3 deg PA500 Position angle of core at 500um
410-413 I4 --- SigniNH2 Detection significance at column density
415-420 F6.2 10+21cm-2 NpH2 Peak H2 column density at 18.2" resolution
422-426 F5.2 --- NpH2/Nbg Contrast over local background at
column density
428-432 F5.2 10+21cm-2 NconvH2 Peak H2 column density at 36.3" resolution
434-438 F5.2 10+21cm-2 NbgH2 Local background H_2 column density
440-442 I3 arcsec FWHMaNH2 Major FWHM diameter of core at NH2
444-446 I3 arcsec FWHMbNH2 Minor FWHM diameter of core at NH2
448-450 I3 deg PANH2 Position angle of core at NH2
452 I1 --- NSED [2/5] Number of significant Herschel bands
454 I1 --- CSARflag [0/3] Associations with CSAR-found cores (1)
456 I1 --- CUTEXflag [0/2] Associations with CUTEX-found
cores (2)
458-459 I2 --- Coretype [-1/4] Core type (G1)
461-500 A40 --- NSIMBAD Closest counterpart found in SIMBAD
502-514 A13 --- NWISE Closest WISE association
516-528 A13 --- NSpitzer Closest Spitzer association
530-603 A74 --- Com Comments
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Note on (1): CSAR flag as follows:
1 = source found independently by CSAR (Kirk et al. 2013MNRAS.432.1424K 2013MNRAS.432.1424K)
within 6" of getsources source
2 = source found within source 50% elliptical contour of getsources source
3 = source found within the mask regions extracted using CSAR
0 = otherwise
Note on (2): CuTEx flag as follows:
1 = source found independently by CuTEx (2011A&A...530A.133M 2011A&A...530A.133M) within 6" of
getsources source
2 = source found within source 50% elliptical contour of getsources source
0 = otherwise
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Byte-by-byte Description of file: tablea2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq [1/239] Core running number
5- 19 A15 --- Name Core name, HHMMSS.s+DDMMSS, to be added
after HGBS_J
21- 22 I2 h RAh Right ascension (J2000)
24- 25 I2 min RAm Right ascension (J2000)
27- 31 F5.2 s RAs Right ascension (J2000)
33 A1 --- DE- Declination sign (J2000)
34- 35 I2 deg DEd Declination (J2000)
37- 38 I2 arcmin DEm Declination (J2000)
40- 43 F4.1 arcsec DEs Declination (J2000)
45- 49 F5.3 pc Rad Core radius as observed (radius)
51- 55 F5.3 --- RadBeam Core radius with 18.2 arcsec beam
(radius_beam)
57- 61 F5.3 Msun Mcore Core mass (Core_mass)
63- 67 F5.3 Msun e_Mcore Uncertainty in core mass (eCoremass)
69- 72 F4.1 K Tdust Dust temperature (Dust_T)
74- 77 F4.1 K e_Tdust Uncertainty in dust temperature (eDustT)
79- 84 F6.2 10+21cm-2 NH2peak Peak H2 column density at 500um
((N_H2)peak)
86- 90 F5.2 10+21cm-2 o Average column density observed
(Avecolumna)
92- 98 F7.2 10+21cm-2 d Average column density deconvolved
(Avecolumnb)
100-105 F6.2 10+4cm-3 nH2peak Beam-averaged peak volume density
((n_H2)peak)
107-112 F6.2 10+4cm-3 <nH2>o Average volume density observed
(Avevolumea)
114-120 F7.2 10+4cm-3 <nH2>d Average volume density deconvolved
(Avevolumeb)
122-127 F6.2 --- Mratio Bonnor-Ebert mass ratio (Bonnor-Ebert)
129-130 I2 --- CType [-1/4] Core type (Core_type) (G1)
132-136 A5 --- Subreg Corona Australis subregion
138-211 A74 --- Com Comments
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right ascension of image center (J2000)
10- 18 F9.5 deg DEdeg Declination of image center (J2000)
20 I1 arcsec/pix Scale [3] Scale of the image
22- 25 I4 --- Nx [8523] Number of pixels along X-axis
27- 30 I4 --- Ny [5702] Number of pixels along Y-axis
32- 37 I6 Kibyte size [379682] Size of the fits file
39- 74 A36 --- FileName Name of the fits file in subdirectory fits
76- 95 A20 --- Title Title of the fits file
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Global notes:
Note on (G1): Core type as follows:
1 = unbound starless
2 = prestellar
3 = candidate prestellar (non-robust)
4 = dense core with embedded protostar
-1 = tentative additional candidate core
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Acknowledgements:
David Bresnahan, DWBresnahan(at)uclan.ac.uk
(End) Patricia Vannier [CDS] 09-Jan-2018