J/ApJ/904/172 Properties of dense cores in Cepheus (Di Francesco+, 2020)
Herschel Gould Belt Survey Observations of Dense Cores in the Cepheus Flare
Clouds.
Di Francesco J., Keown J., Fallscheer C., Andre P., Ladjelate B.,
Konyves V., Men'shchikov A., Stephens-Whale S., Nguyen-Luong Q., Martin P.,
Sadavoy S., Pezzuto S., Fiorellino E., Benedettini M., Schneider N.,
Bontemps S., Arzoumanian D., Palmeirim P., Kirk J.M., Ward-Thompson D.
<Astrophys. J., 904, 172 (2020)>
=2020ApJ...904..172D 2020ApJ...904..172D
ADC_Keywords: Interstellar medium; YSOs; Star Forming Region;
Photometry, infrared; Photometry, millimetric/submm
Keywords: Interstellar medium ; Young stellar objects ; Star formation ;
Protostars ; Initial mass function ; Dense interstellar clouds ;
Molecular clouds ; Interstellar filaments
Abstract:
We present Herschel SPIRE and PACS maps of the Cepheus Flare clouds
L1157, L1172, L1228, L1241, and L1251, observed by the Herschel Gould
Belt Survey of nearby star-forming molecular clouds. Through modified
blackbody fits to the SPIRE and PACS data, we determine typical cloud
column densities of (0.5-1.0)x1021/cm2 and typical cloud
temperatures of 14-15K. Using the getsources identification algorithm,
we extract 832 dense cores from the SPIRE and PACS data at
160-500µm. From placement in a mass versus size diagram, we
consider 303 to be candidate prestellar cores, and 178 of these to be
"robust" prestellar cores. From an independent extraction of sources
at 70µm, we consider 25 of the 832 dense cores to be protostellar.
The distribution of background column densities coincident with
candidate prestellar cores peaks at (2-4)x1021/cm2. About half of
the candidate prestellar cores in Cepheus may have formed as a result
of the widespread fragmentation expected to occur within filaments of
"transcritical" line mass. The lognormal robust prestellar core mass
function (CMF) drawn from all five Cepheus clouds peaks at 0.56M☉
and has a width of ∼0.5dex, similar to that of Aquila's CMF. Indeed,
the width of Cepheus's aggregate CMF is similar to the stellar system
initial mass function (IMF). The similarity of CMF widths in different
clouds and the system IMF suggests a common, possibly turbulent origin
for seeding the fluctuations that evolve into prestellar cores and
stars.
Description:
Each Cepheus field was observed simultaneously with the Herschel Space
Observatory's Spectral and Photometric Imaging Receiver (SPIRE) and
Photodetector Array Camera and Spectrometer (PACS) instruments in
parallel mode, as part of the Herschel Gould Belt Survey (HGBS) Key
Program. Table 1 summarizes the Herschel observations of the five
Cepheus fields.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 68 6 Details of Herschel observations
tablec1.dat 581 832 Observed properties of dense cores in Cepheus
tablec2.dat 183 832 Derived properties of dense cores in Cepheus
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See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/ApJ/428/693 : Rosette Nebula and Maddalena Cloud structures (Williams+ 1994)
J/ApJS/110/21 : Molecular clouds in Cepheus and Cassiopeia (Yonekura+ 1997)
J/ApJS/179/249 : Low-luminosity embedded protostar population (Dunham+, 2008)
J/A+A/487/993 : MAMBO Mapping of c2d Clouds and Cores (Kauffmann+, 2008)
J/ApJS/185/198 : The Cepheus flare observed with IRAC and MIPS (Kirk+, 2009)
J/A+A/584/A91 : Catalog of dense cores Aquila from Herschel (Konyves+, 2015)
J/MNRAS/459/342 : Dense cores in Taurus L1495 cloud (Marsh+, 2016)
J/A+A/619/A52 : Dense cores and YSOs in Lupus complex (Benedettini+, 2018)
J/A+A/615/A125 : Molecular cloud in Corona Australis (Bresnahan+, 2018)
J/ApJ/867/151 : YSOs in Gould Belt regions with Gaia-DR2 data (Dzib+, 2018)
J/A+A/635/A34 : Catalog of dense cores Orion B from Herschel (Konyves+, 2020)
J/A+A/638/A74 : Catalog of dense cores Oph molecular cloud (Ladjelate+, 2020)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Cloud Cloud identifier
7- 19 F13.9 deg RAdeg [310/339] Degree of right ascension (J2000)
21- 33 F13.10 deg DEdeg [67.7/77.5] Degree of declination (J2000)
35- 38 I4 yr Obs.Y [2009/2010] Year of observation
40- 42 A3 "month" Obs.M Month of observation
44- 45 I2 d Obs.D Day of observation
47- 68 A22 --- ObsID Observation identifiers
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Byte-by-byte Description of file: tablec1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Cloud Cloud identifier
7- 9 I3 --- Seq [1/205] Core running number
11- 31 A21 --- Name Core name, HGBS JHHMMSS.s+DDMMSS
33- 34 I2 h RAh [20/22] Hour of Right Ascension (J2000)
36- 37 I2 min RAm Minute of Right Ascension (J2000)
39- 43 F5.2 s RAs Second of Right Ascension (J2000)
45 A1 --- DE- [+] Sign of declination (J2000)
46- 47 I2 deg DEd [66/78] Degree of Declination (J2000)
49- 50 I2 arcmin DEm Arcminute of Declination (J2000)
52- 56 F5.2 arcsec DEs Arcsecond of Declination (J2000)
58- 63 F6.1 --- Signi70 [0/4732]?=0.0 Detection significance at
70um (1)
65- 73 E9.2 Jy/beam Sp70 [-0.93/54.6] Peak intensity at 70um
75- 81 E7.1 Jy/beam e_Sp70 [1e-30/4] Error in Sp70
83- 89 F7.3 --- Sp70/Sbg70 [-15.8/915] Contrast over local
background at 70um
91- 99 E9.2 Jy/beam Sconv70 [-6.07/63.9] Smoothed peak intensity at
70um (2)
101-109 E9.2 Jy Stot70 [-11.4/135] Total integrated flux density
at 70um
111-117 E7.1 Jy e_Stot70 [1e-30/7] Error in Stot70
119-123 F5.1 arcsec FWHMa70 [8.4/212]?=-1 Major FWHM diameter at 70um
125-129 F5.1 arcsec FWHMb070 [8.4/179.8]?=-1 Minor FWHM diameter at
70um
131-135 F5.1 deg PA070 [0/179.8]?=-1 Position angle at 70um (3)
137-142 F6.1 --- Signi160 [0.0/3122.0] Detection significance at
160um (1)
144-152 E9.2 Jy/beam Sp160 [-0.082/52.2] Peak intensity at 160um
154-160 E7.1 Jy/beam e_Sp160 [0.0012/4.1] Error in Sp160
162-168 F7.3 --- Sp160/Sbg160 [-13.618/102.576] Contrast over local
background at 160 um
170-178 E9.2 Jy/beam Sconv160 [-0.214/83.3] Smoothed peak intensity at
160um (2)
180-188 E9.2 Jy Stot160 [-0.155/120.0] Total integrated flux
density at 160um
190-196 E7.1 Jy e_Stot160 [0.002/6.8] Error in Stot160
198-202 F5.1 arcsec FWHMa160 [13.5/189.6]?=-1 Major FWHM diameter at
160um
204-208 F5.1 arcsec FWHMb160 [13.5/180]?=-1 Minor FWHM diameter at
160um
210-214 F5.1 deg PA160 [0/180]?=-1 Position angle at 160um (3)
216-221 F6.1 --- Signi250 [0/2862] Detection significance at 250um
(1)
223-231 E9.2 Jy/beam Sp250 [-0.02/41.5] Peak intensity at 250um
233-239 E7.1 Jy/beam e_Sp250 [1e-30/3] Error in Sp250
241-248 F8.3 --- Sp250/Sbg250 [-41.96/1139] Contrast over local
background at 250um
250-258 E9.2 Jy/beam Sconv250 [-0.03/38.6] Smoothed peak intensity at
250um (2)
260-267 E8.2 Jy Stot250 [0.01/63] Total integrated flux density
at 250um
269-275 E7.1 Jy e_Stot250 [1e-30/4] Error in Stot250
277-281 F5.1 arcsec FWHMa250 [18.2/169]?=-1 Major FWHM diameter at
250um
283-286 F4.1 arcsec FWHMb250 [18.2/89.3]?=-1 Minor FWHM diameter at
250um
288-292 F5.1 deg PA250 [0.3/180]?=-1 Position angle at 250um (3)
294-299 F6.1 --- Signi350 [0/1982] Detection significance at
350um (1)
301-309 E9.2 Jy/beam Sp350 [-0.12/28.1] Peak intensity at 350um
311-317 E7.1 Jy/beam e_Sp350 [0.0029/1.2] Error in Sp350
319-325 F7.3 --- Sp350/Sbg350 [-87.5/21.2] Contrast over local
background at 350um
327-335 E9.2 Jy/beam Sconv350 [-0.14/26.4] Smoothed peak intensity at
350um (2)
337-345 E9.2 Jy Stot350 [-0.37/32.7] Total integrated flux
density at 350um
347-353 E7.1 Jy e_Stot350 [0.002/1.2] Error in Stot350
355-359 F5.1 arcsec FWHMa350 [24.9/158]?=-1 Major FWHM diameter at
350um
361-365 F5.1 arcsec FWHMb350 [24.9/112]?=-1 Minor FWHM diameter at
350um
367-371 F5.1 deg PA350 [0.3/180]?=-1 Position angle at 350um (3)
373-378 F6.1 --- Signi500 [0/1213] Detection significance at 500um
(1)
380-387 E8.2 Jy/beam Sp500 [1.8e-18/17.4] Peak intensity at 500um
389-395 E7.1 Jy/beam e_Sp500 [1e-30/0.48] Error in Sp500
397-403 F7.3 --- Sp500/Sbg500 [-66.6/33] Contrast over local background
at 500um
405-413 E9.2 Jy Stot500 [-0.22/18.5] Total integrated flux
density at 500um
415-421 E7.1 Jy e_Stot500 [1e-30/0.48] Error in Stot500 at 500um
423-427 F5.1 arcsec FWHMa500 [36.3/158]?=-1 Major FWHM diameter at
500um
429-433 F5.1 arcsec FWHMb500 [36.3/109]?=-1 Minor FWHM diameter at
500um
435-439 F5.1 deg PA500 [0.7/180]?=-1 Position angle at 500um (3)
441-446 F6.1 --- SigniNH2 [5/1250] Detection significance at
column density
448-452 F5.1 10+21/cm2 NpH2 [2.4/819] Peak H2 column density at
18.2" resolution
454-456 F3.1 --- NpH2/NbgH2 [0.1/6.8] Contrast over local background
at column density
458-460 F3.1 10+21/cm2 NconvH2 [0.0/8.4] Peak H2 column density in a
36.3" resolution
462-468 F7.3 10+21/cm2 NbgH2 [3.675/211] Local background H2 column
density
470-476 F7.3 arcsec FWHMaNH2 [18.2/160] Major FWHM diameter of core at
NH2
478-484 F7.3 arcsec FWHMbNH2 [18.2/117] Minor FWHM diameter of core at
NH2
486-490 F5.1 deg PANH2 [0.5/180] Position angle of core at NH2
(3)
492 I1 --- NSED [0/5] Number significant Herschel bands
494 I1 --- CSARflag [0/1] Identified by CSAR flag (4)
496-507 A12 --- Coretype Core type (5)
509-535 A27 --- NSIMBAD SIMBAD counterparts within 6arcsec
537-564 A28 --- NNED NED counterparts within 6arcsec
566-581 A16 --- NSPITZER SPITZER counterparts within 6arcsec (6)
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Note (1): Detection significance, derived by getsources (Men'shchikov+,
2012A&A...542A..81M 2012A&A...542A..81M).
Note (2): Peak flux density at the specified wavelength, measured after
smoothing the data to a 36.3" beam.
Note (3): Position angle of the core major axis, measured east of north.
Note (4): CSARflag: 2 if the getsources core has a counterpart
detected by CSAR (Kirk+, 2013MNRAS.432.1424K 2013MNRAS.432.1424K) within 6 arcsec of its
peak position, 1 if no close CSAR counterpart was found but the peak
position of a CSAR source lies within the FWHM contour of the
getsources core in the high-resolution column density map, 0
otherwise.
Note (5): Coretype: starless, prestellar, or protostellar.
Note (6): Closest Spitzer-identified YSO from Kirk+, J/ApJS/185/198
within 6-arcsec of the Herschel peak position, if any.
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Byte-by-byte Description of file: tablec2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Cloud Cloud identifier
7- 9 I3 --- Seq [1/205] Core running number
11- 31 A21 --- Name Core name, HGBS JHHMMSS.s+DDMMSS
33- 34 I2 h RAh [20/22] Hour of Right Ascension (J2000)
36- 37 I2 min RAm Minute of Right Ascension (J2000)
39- 43 F5.2 s RAs Second of Right Ascension (J2000)
45 A1 --- DE- [+] Sign of declination (J2000)
46- 47 I2 deg DEd [66/78] Degree of Declination (J2000)
49- 50 I2 arcmin DEm Arcminute of Declination (J2000)
52- 56 F5.2 arcsec DEs Arcsecond of Declination (J2000)
58- 64 E7.1 pc Rd [6.6e-10/0.23] Deconvolved core radius (1)
66- 72 E7.1 pc Robs [0.03/0.24] Observed core radius (2)
74- 79 F6.3 solMass Mcore [-0.13/10.1] Estimated core mass
81- 84 F4.2 solMass e_Mcore [0/8.76]? Uncertainty in Mcore
86- 89 F4.1 K Tdust [5.8/33.2] Dust temperature from SED
fitting
91- 93 F3.1 K e_Tdust [0/6.8]? Uncertainty in the Tdust
95-103 E9.2 10+21/cm2 NH2peak [-2.91e+18/2.4e+29] Peak H2 column density
at 36.3" resolution
105-113 E9.2 10+21/cm2 NH2av [-3.32e+20/1.9e+37] Average NH2 derived
with Robs
115-123 E9.2 10+21/cm2 NH2avd [-2.8e+20/7.8e+22] Average NH2 derived
with Rd
125-133 E9.2 10+4/cm3 nH2peak [-2.91e+18/1120000000000] Beam-averaged
Peak volume density
135-143 E9.2 10+4/cm3 nH2av [-1120/6.9e+27] Average core volume
density from Robs
145-153 E9.2 10+4/cm3 nH2avd [-862/551000] Average core volume density
155-159 F5.1 --- alphaBE [-13.3/357] Bonnor-Ebert mass ratio
161-172 A12 --- Coretype Core type (3)
174-183 A10 --- Com Comments (4)
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Note (1): Geometrical average between the major and minor FWHM sizes of the
core [pc], measured in the high-resolution column density map after
deconvolution from the 18.2arcsec HPBW resolution of the map.
Note (2): Same as Note (1) before deconvolution.
Note (3): Core type: starless, prestellar, protostellar.
Note (4): Comments may be either "no SED fit" or "None."
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 21-Mar-2022