J/MNRAS/532/4661 178 dense cores study with HGBS of TMC1 -II (Kirk+, 2024)
Herschel Gould Belt Survey in Taurus - II. A census of dense cores and
filaments in the TMC1 region.
Kirk J.M., Ward-Thompson D., Di Francesco J., Andre P., Bresnahan D.W.,
Konyves V., Marsh K., Griffin M.J., Schneider N., Men'shchikov A.,
Palmeirim P., Bontemps S., Arzoumanian D., Benedettini M., Pezzuto S.
<Mon. Not. R. Astron. Soc. 532, 4661-4680 (2024)>
=2024MNRAS.532.4661K 2024MNRAS.532.4661K (SIMBAD/NED BibCode)
ADC_Keywords: YSOs ; Molecular clouds ; Interstellar medium ; Photometry ;
Spectroscopy ; Infrared ; Millimetric/submm sources ;
Positional data ; Molecular data
Keywords: catalogues - stars - formation - ISM: clouds -
ISM: individual objects: TMC1 molecular cloud - ISM structure -
submillimetre: ISM
Abstract:
We present a catalogue of dense cores and filaments in a
3.8°*2.4° field around the TMC1 region of the Taurus molecular
cloud. The catalogue was created using photometric data from the
Herschel SPIRE and PACS instruments in the 70, 160, 250, 350, and 500
µm continuum bands. Extended structure in the region was
reconstructed from a Herschel column density map. Power spectra and
probability density functions (PDFs) of this structure are presented.
The PDF splits into lognormal and power-law forms, with the high-
density power-law component associated primarily with the central part
of TMC1. The total mass in the mapped region is 2000 M☉, of
which 34 per cent is above an extinction of AV ∼ 3 mag - a level
that appears as a break in the PDF and as the minimum column density
at which dense cores are found. A total of 35 dense filaments were
extracted from the column density map. These have a typical full width
at half-maximum (FWHM) width of 0.07 pc, but the TMC1 filament itself
has a mean FWHM of ∼ 0.13pc. The thermally supercritical filaments in
the region are aligned orthogonal to the prevailing magnetic field
direction. Derived properties for the supercritical TMC1 filament
support the scenario of it being relatively young. A catalogue of 44
robust and candidate prestellar cores is created and is assessed to be
complete down to 0.1 M☉. The combined prestellar core mass
function for the TMC1 and L1495 regions is well fit by a single
lognormal distribution and is comparable to the standard initial mass
function.
Description:
In this study, we present Hershel photometric and spectroscopic
observations of TMC1 region in PACS/SPIRE FIR and submillimetre
regimes. With these observations, we constructed high definition
density maps, SEDs and photometric maps. As resumed in section 6,
catalogs are focused on cores as pre/prostellar and unbound ones. The
core candidates was assessed by comparing the getsources extraction to
the results of a csar extraction performed on the high-resolution
column density map. Hence, photometric/spectroscopic results from
observations, column densities and core types are presented in
tableb1.dat while derived physical properties as masses, temperatures,
geometrical radius and computed average column densities are provided
in tableb2.dat.
As described in section 6.1, a set of selection rules was applied to
each of the photometric catalogues to create science catalogues. A
catalogue of dense core candidates was created by filtering the
extended source yielding to 178 dense core candidates.
Objects:
----------------------------------------------------------------------------
RA (2000) DE Designation(s)
----------------------------------------------------------------------------
04 40 59.99 +25 52 00.0 NAME Taurus Complex = NAME TAURUS MOL CLOUD
04 41 45.89 +25 41 27.0 TMC-1 = HCL 2 = MLB 3-28
----------------------------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tableb1.dat 461 178 Dense cores identified in the HGBS maps of the
TMC1 Region of the TMC
tableb2.dat 157 178 Derived properties of the dense cores identified
in the HGBS maps of the TMC1 Region of the TMC
--------------------------------------------------------------------------------
See also:
J/MNRAS/459/342 : Dense cores in Taurus L1495 cloud (Marsh+, 2016)
J/A+A/658/A166 : 4 star-forming regions 3D dust density (Dharmawardena+, 2022)
J/A+A/645/A55 : Catalogue of cold cores in Perseus (Pezzuto+, 2021)
J/A+A/638/A74 : Catalog of dense cores in Oph molecular cloud
(Ladjelate+, 2020)
J/A+A/630/A137 : Structure and kinematics of the Taurus region (Galli+, 2019)
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/A+A/594/A28 : Planck Catalogue of Galactic cold clumps (PGCC)
(Planck+, 2016)
J/A+A/584/A91 : Catalog of dense cores in Aquila from Herschel
(Konyves+, 2015)
J/A+A/575/A79 : SPIRE 250um maps of 4 molecular clouds (Schneider+, 2015)
J/A+A/487/993 : MAMBO Mapping of c2d Clouds and Cores (Kauffmann+, 2008)
J/ApJ/904/172 : Properties of dense cores in Cepheus (Di Francesco+, 2020)
J/ApJS/186/259 : Taurus Spitzer survey: new candidate members (Rebull+, 2010)
J/AJ/162/110 : Gaia EDR3 census of the Taurus-Auriga complex
(Krolikowski+, 2021)
J/AJ/158/54 : New Taurus members from stellar to planetary masses
(Esplin+, 2019)
J/AJ/156/271 : The stellar membership of the Taurus SFR (Luhman, 2018)
VII/7A : Lynds' Catalogue of Dark Nebulae (LDN) (Lynds 1962)
Byte-by-byte Description of file: tableb1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Core Core source raw number (C.No.)
5- 19 A15 --- HGBS Source name prefix as HGBS_J followed
by the label derived from J2000
sexagesimal coordinates (Source_name)
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- 50 F6.1 --- Sig70 Detection significance at 70µm PACS
filter as explicited in section 6.1
Catalogue creation (Sig70)
52- 60 E9.3 Jy/beam S70pk Peak flux density at 70µm PACS
filter estimated by getsources
(S{peak}70)
62- 68 E7.2 Jy/beam e_S70pk Mean uncertainty of S70peak
(errS{peak}70)
70- 75 F6.2 --- S70pk/Sbg Intensity contrast at 70µm PACS
filter (Speak70/Sbg) (1)
77- 85 E9.3 Jy/beam S70smpk Peak flux density estimate at 70µm
PACS filter in a uniform 36.3 arcsec
beam (Sconv,50070)
87- 95 E9.3 Jy F70 Integrated flux density at 70µm PACS
filter as estimated by getsources
(Stot70)
97-104 E8.2 Jy e_F70 [] Mean uncertainty of F70
(errStot70)
106-108 I3 arcsec FWHMmaj70 Major FWHM diameter of the core at
70µm PACS filter as estimated by
getsources (a70)
110-112 I3 arcsec FWHMmin70 Minor FWHM diameter of the core at
70µm PACS filter as estimated by
getsources (b70)
114-116 I3 deg PA70 Position angle of the core major axis
east of north at 70µm PACS filter
(PA70)
118-123 F6.1 --- Sig160 Detection significance at 160µm PACS
filter as explicited in section 6.1
Catalogue creation (Sig160)
125-133 E9.3 Jy/beam S160pk Peak flux density at 160µm PACS
filter estimated by getsources
(Speak160)
135-141 E7.2 Jy/beam e_S160pk Mean uncertainty of S160peak
(errSpeak160)
143-148 F6.2 --- S160pk/Sbg Intensity contrast at 160µm PACS
filter (Speak160/Sbg) (1)
150-158 E9.3 Jy/beam S160smpk Peak flux density estimate at 160µm
PACS filter in a uniform 36.3 arcsec
beam (Sconv,500160)
160-168 E9.3 Jy F160 Integrated flux density at 160µm
PACS filter as estimated by getsources
(Stot160)
170-177 E8.2 Jy e_F160 [] Mean uncertainty of F160
(errStot160)
179-181 I3 arcsec FWHMmaj160 Major FWHM diameter of the core at
160µm PACS filter as estimated by
getsources (a160)
183-185 I3 arcsec FWHMmin160 Minor FWHM diameter of the core at
160µm PACS filter as estimated by
getsources (b160)
187-189 I3 deg PA160 Position angle of the core major axis
east of north at 160µm PACS filter
(PA160)
191-196 F6.1 --- Sig250 Detection significance at 250µm
SPIRE filter as explicited in section
6.1 Catalogue creation (Sig250)
198-205 E8.3 Jy/beam S250pk Peak flux density at 250µm SPIRE
filter estimated by getsources
(Speak250)
207-213 E7.2 Jy/beam e_S250pk Mean uncertainty of S350peak
(errSpeak350)
215-220 F6.2 --- S250pk/Sbg Intensity contrast at 250µm SPIRE
filter (Speak250/Sbg) (1)
222-229 E8.3 Jy/beam S250smpk Peak flux density estimate at 250µm
SPIRE filter in a uniform 36.3 arcsec
beam (Speak250)
231-238 E8.3 Jy F250 Integrated flux density at 250µm
SPIRE filter as estimated by getsources
(Stot250)
240-246 E7.2 Jy e_F250 Mean uncertainty of F250
(errStot250)
248-250 I3 arcsec FWHMmaj250 Major FWHM diameter of the core at
250µm SPIRE filter as estimated by
getsources (a250)
252-254 I3 arcsec FWHMmin250 Minor FWHM diameter of the core at
250µm SPIRE filter as estimated by
getsources (b250)
256-258 I3 deg PA250 Position angle of the core major axis
east of north at 250µm SPIRE filter
(PA250)
260-264 F5.1 --- Sig350 Detection significance at 350µm
SPIRE filter as explicited in section
6.1 Catalogue creation (Sig350)
266-273 E8.3 Jy/beam S350pk Peak flux density at 350µm SPIRE
filter estimated by getsources
(Speak350)
275-281 E7.2 Jy/beam e_S350pk Mean uncertainty of S350peak
(errSpeak350)
283-288 F6.2 --- S350pk/Sbg Intensity contrast at 350µm SPIRE
filter (Speak350/Sbg) (1)
290-297 E8.3 Jy/beam S350smpk Peak flux density estimate at 350µm
SPIRE filter in a uniform 36.3 arcsec
beam (Sconv,500{350})
299-306 E8.3 Jy F350 Integrated flux density at 350µm
SPIRE filter as estimated by getsources
(Stot350)
308-314 E7.2 Jy e_F350 Mean uncertainty of F350
(errStot350)
316-318 I3 arcsec FWHMmaj350 Major FWHM diameter of the core at
350µm SPIRE filter as estimated by
getsources (a350)
320-322 I3 arcsec FWHMmin350 Minor FWHM diameter of the core at
350µm SPIRE filter as estimated by
getsources (b350)
324-326 I3 deg PA350 Position angle of the core major axis
east of north at 350µm SPIRE filter
(PA350)
328-332 F5.1 --- Sig500 Detection significance at 500µm
SPIRE filter as explicited in section
6.1 Catalogue creation (Sig500)
334-341 E8.3 Jy/beam S500pk Peak flux density at 500µm SPIRE
filter estimated by getsources
(Speak500)
343-349 E7.2 Jy/beam e_S500pk Mean uncertainty of S500peak
(errSpeak500)
351-355 F5.2 --- S500pk/Sbg Intensity contrast at 500µm SPIRE
filter (Speak500/Sbg) (1)
357-365 E9.3 Jy F500 Integrated flux density at 500µm
SPIRE filter as estimated by getsources
(Stot500)
367-374 E8.2 Jy e_F500 [] Mean uncertainty of F500
(errStot500)
376-378 I3 arcsec FWHMmaj500 Major FWHM diameter of the core at
500µm SPIRE filter as estimated by
getsources (a500)
380-382 I3 arcsec FWHMmin500 Minor FWHM diameter of the core at
500µm SPIRE filter as estimated by
getsources (b500)
384-386 I3 deg PA500 Position angle of the core major axis
east of north at 500µm SPIRE filter
(PA500)
388-392 F5.1 --- SigNH2 Detection significance in the
high-resolution column density image
(SigNH2)
394-401 E8.3 10+21cm-2 NH2pk Peak H2 column density as estimated
by getsources in the high-resolution
column density image (NpeakH2)
403-406 F4.2 --- NH2pk/Nbg Column density NH2 contrast in the
high-resolution column density image
(NpeakH2/Nbg) (2)
408-415 E8.3 10+21cm-2 NH2smpk Peak H2 column density measured in a
36.3 arcsec beam (Nconv,500H2)
417-424 E8.3 10+21cm-2 NH2bg Local background H2 column density by
getsources in the high-resolution column
density image (NbgH2)
426-428 I3 arcsec FWHMH2maj Major FWHM diameters of the core in the
high-resolution column density map as
estimated by getsources (aNH2)
430-432 I3 arcsec FWHMH2min Minor FWHM diameters of the core in the
high-resolution column density map as
estimated by getsources (bNH2)
434-436 I3 arcsec PAH2 Position angle of the core major axis
east of north in the high-resolution
column density map as estimated by
getsources (PANH2)
438 I1 --- CSAR ? Counterpart whether the getsources
core has a counterpart detected by the
CSAR source-finding algorithm (CSAR) (3)
440 I1 --- Nband Number of Herschel bands (NSED) (4)
442-461 A20 --- Type Core type (Type) (G1)
--------------------------------------------------------------------------------
Note (1): Contrast over the local background as the ratio of
background-subtracted peak intensity to local background intensity
at 70µm PACS filter, 160µm PACS filter, 250µm SPIRE filter,
350µm SPIRE filter or 500µm SPIRE filter.
Note (2): Column density contrast over the local background in the
high-resolution column density image defined as the ratio of the
background-subtracted peak column density to the local background
intensity.
Note (3): CSAR source-finding algorithm counterpart performed on the
high-resolution column density map are as follows:
0 = getsources core has not a counterpart detected by the CSAR,
31 sources in our sample
1 = if the the CSAR counterpart is within an ellipse half (equivalent
to the half-width) the size of the 50 per cent contour of the
getsources core at 250µm, 86 sources in our sample
2 = if the the CSAR counterpart is within the 50% contour of the
getsources core at 250um (full-width), 2 sources in our sample
3 = if the getsources core is conincident with extended emission
associated with a CSAR source, 59 sources in our sample
Note (4): Nband in which the core is significant Sigλ > 5 and has a
positive flux density excluding the column density plane.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tableb2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Core Core source raw number (C.No.)
5- 19 A15 --- HGBS Source name prefix as HGBS_J followed by
the label derived from J2000 sexagesimal
coordinates (Source_name)
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 RcoreB Geometrical average between the major and
minor FWHM sizes of the core before
deconvolution (Rcorebefore) (1)
51- 55 F5.3 pc RcoreA Geometrical average between the major and
minor FWHM sizes of the core after
deconvolution (Rcoreafter) (1)
57- 61 F5.3 Msun Mcore Estimated core mass assuming the dust
opacity law advocated by Roy et al.
2014A&A...562A.138R 2014A&A...562A.138R (Mcore)
63- 68 F6.3 Msun e_Mcore Mean uncertainty of Mcore (errMcore) (2)
70- 73 F4.1 K Tcore The SED dust temperature (Tcore)
75- 78 F4.1 K e_Tcore Mean uncertainty of Tcore (errTcore) (2)
80- 87 E8.3 10+21cm-2 NH2pk Peak H2 column density at the
resolution of the 500µm data
(NpeakH2) (3)
89- 95 E7.2 10+21cm-2 NH2avB Average column density calculated with
radius RcoreB (NaveH2before) (4)
97-103 E7.2 10+21cm-2 NH2avA ? Average column density calculated with
radius RcoreA (NaveH2after) (4)
105-111 E7.2 10+4cm-3 nH2avB Average volume density calculated with
radius RcoreB (naveH2before) (5)
113-119 E7.2 10+4cm-3 nH2avA ? Average volume density calculated with
radius RcoreA (naveH2after) (5)
121-125 F5.1 --- alpha Bonnor-Ebert mass ratio (αBE) (6)
127-146 A20 --- Type Core type (Type) (G1)
148-157 A10 --- Comments Wether a SED fit or not where no for 76
and yes for 102 sources in our sample
(Comments)
--------------------------------------------------------------------------------
Note (1): As detailed in section 6.2 Core properties, geometrical average
between the major and minor FWHM sizes of the core as measured in
the high-resolution column density map before deconvolution, and
after deconvolution from the 18.2 arcsec half-power beam width (HPBW)
resolution of the map respectively.
Note (2): Statistical errors on the mass and temperature, respectively,
including calibration uncertainties, but excluding dust opacity
uncertainties.
Note (3): Derived from a graybody SED fit to the core peak flux densities
measured in a common 36.3 arcsec beam at all wavelengths.
Note (4): Calculated as Mcore/πR2core * 1/µmH under the assumption
of circular cross section where Mcore is the estimated core mass
and Rcore the estimated core radius prior to deconvolution and
µ = 2.86.
Note (5): Calculated as Mcore/(4/3)πR3core*1/µmH under the
assumption of purely spherical volume where Mcore is the estimated
core mass and Rcore the estimated core radius prior to deconvolution
and µ = 2.86.
Note (6): As defined in section 6.3, an estimate of the stabilities of the cores
can be made by comparing their masses to that of a critical
Bonner-Ebert (BE) sphere. A BE sphere is a pressure-confined
isothermal sphere of gas that will be unstable against collapse if its
mass is above a critical value given by equation 4.
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Global notes:
Note (G1): As described in section 6, cores type are as follows:
protostellar = protostellar core, 10 sources in our sample
candidate prestellar = candidate prestellar core, 17 sources in our
sample
robust prestellar = robust prestellar core, 27 sources in our
sample
unbound starless = unbound starless core, 123 sources in our
sample
unknown = unknown core, 1 source in our sample
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History:
From electronic version of the journal
References:
Marsh et al., Paper I 2016MNRAS.459..342M 2016MNRAS.459..342M, Cat. J/MNRAS/459/342
(End) Luc Trabelsi [CDS] 03-Sep-2025