J/A+A/689/A3 Filamentary structure in California from Herschel (Zhang+, 2024)
Probing the filamentary nature of star formation in the California giant
molecular cloud.
Zhang G.-Y., Andre P., Men'shchikov A., Li J.-Z.
<Astron. Astrophys. 689, A3 (2024)>
=2024A&A...689A...3Z 2024A&A...689A...3Z (SIMBAD/NED BibCode)
ADC_Keywords: Interstellar medium ; Molecular clouds ; Photometry, surface ;
Photometry, RI
Keywords: stars: formation - ISM: clouds - dust, extinction - submillimeter: ISM
Abstract:
Recent studies suggest that filamentary structures are representative
of the initial conditions of star formation in molecular clouds and
support a filament paradigm for star formation, potentially accounting
for the origin of the stellar initial mass function (IMF). The
detailed, local physical properties of molecular filaments remain
poorly characterized, however.
Using Herschel imaging observations of the California giant molecular
cloud, we aim to further investigate the filament paradigm for low- to
intermediate-mass star formation and to better understand the exact
role of filaments in the origin of stellar masses.
Using the multiscale, multiwavelength extraction method getsf, we
identify starless cores, protostars, and filaments in the Herschel
data set and separate these components from the background cloud
contribution to determine accurate core and filament properties.
We find that filamentary structures contribute approximately 20% of
the overall mass of the California cloud, while dense cores contribute
a mere 2% of the total mass. The transverse half-power diameter
measured for California molecular filaments has a median undeconvolved
value of 0.18pc, consistent within a factor of 2 with the typical
∼0.1pc width of nearby filaments from the Herschel Gould Belt survey.
A vast majority of identified prestellar cores (∼82-90%) are located
within ∼0.1pc of the spines of supercritical filamentary structures.
Both the prestellar core mass function (CMF) and the distribution of
filament masses per unit length or filament line mass function (FLMF)
are consistent with power- law distributions at the high-mass end,
{DELTA}N/{DELTA}logM~=M-1.4±0.2 at M>1M☉ for the CMF and
{DELTA}N/{DELTA}logMline~=Mline-1.5±0.2 for the FLMF at
Mline>10M☉/pc, which are both consistent with the Salpeter
power-law IMF. Based on these results, we propose a revised model for
the origin of the CMF in filaments, whereby the global prestellar CMF
in a molecular cloud arises from the integration of the CMFs generated
by individual thermally supercritical filaments within the cloud.
Our findings support the existence a tight connection between the FLMF
and the CMF/IMF and suggests that filamentary structures represent a
critical evolutionary step in establishing a Salpeter-like mass
function.
Description:
This dataset is part of the study probing the filamentary nature of
star formation in the California giant molecular cloud. The study
identifies and characterizes filamentary structures and their
relationship with star formation. The data includes a 18.2"
high-resolution column density map and a global skeleton tracing
filamentary structures on all scales, independently of the filament
widths.
Objects:
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RA (2000) DE Designation(s)
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04 10.0 +39 00 California GMC = NAME California Molecular Cloud
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 118 2 List of fits files
fits/* . 2 Individual fits files
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See also:
J/ApJ/764/133 : Auriga-California giant molecular cloud (Harvey+, 2013)
J/ApJ/786/37 : Auriga-California molecular cloud (Broekhoven-Fiene+, 2014)
J/A+A/606/A100 : YSOs in California Molecular Cloud (Lada+, 2017)
J/A+A/620/A163 : Cores in California molecular cloud (Zhang+, 2018)
J/A+A/642/A76 : California molecular cloud CO datacubes (Zhang+, 2020)
J/ApJ/921/23 : C18O dense cores identified in the CMC region (Guo+, 2021)
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 center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 23 I4 --- Nx Number of pixels along X-axis
25- 28 I4 --- Ny Number of pixels along Y-axis
30- 34 I5 Kibyte size Size of FITS file
36- 84 A49 --- FileName Name of FITS file, in subdirectory fits
86-118 A33 --- Title Title of the FITS file
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Acknowledgements:
Guo-Yin Zhang, zgyin(at)nao.cas.cn
Philippe Andre, philippe.andre(at)cea.fr
Alexander Menshchikov, alexander.menshchikov(at)cea.fr
References:
Andre et al., 2019A&A...629L...4A 2019A&A...629L...4A
Men'shchikov, 2021A&A...649A..89M 2021A&A...649A..89M
(End) Guo-Yin Zhang [NAOC, CAS, China], Patricia Vannier [CDS] 10-Jun-2024