2016A&A...592A..61L


C.D.S. - SIMBAD4 rel 1.7 - 2019.10.19CEST07:46:55

2016A&A...592A..61L - Astronomy and Astrophysics, volume 592A, 61-61 (2016/8-1)

Earliest phases of star formation (EPoS) Dust temperature distributions in isolated starless cores.

LIPPOK N., LAUNHARDT R., HENNING T., BALOG Z., BEUTHER H., KAINULAINEN J., KRAUSE O., LINZ H., NIELBOCK M., RAGAN S.E., ROBITAILLE T.P., SADAVOY S.I. and SCHMIEDEKE A.

Abstract (from CDS):

Context. Stars form by the gravitational collapse of cold and dense molecular cloud cores. Constraining the temperature and density structure of such cores is fundamental for understanding the initial conditions of star formation. We use Herschel observations of the thermal far-infrared (FIR) dust emission from nearby and isolated molecular cloud cores and combine them with ground-based submillimeter continuum data to derive observational constraints on their temperature and density structure.
Aims. The aim of this study is to verify the validity of a ray-tracing inversion technique developed to derive the dust temperature and density structure of nearby and isolated starless cores directly from the dust emission maps and to test if the resulting temperature and density profiles are consistent with physical models.
Methods. We have developed a ray-tracing inversion technique that can be used to derive the temperature and density structure of starless cores directly from the observed dust emission maps without the need to make assumptions about the physical conditions. Using this ray-tracing inversion technique, we derive the dust temperature and density structure of six isolated starless molecular cloud cores from dust emission maps in the wavelengths range 100µm-1.2mm. We then employ self-consistent radiative transfer modeling to the density profiles derived with the ray-tracing inversion method. In this model, the interstellar radiation field (ISRF) is the only heating source. The local strength of the ISRF as well as the total extinction provided by the outer envelope are treated as semi-free parameters which we scale within defined limits. The best-fit values of both parameters are derived by comparing the self-consistently calculated temperature profiles with those derived by the ray-tracing method.
Results. We confirm earlier results and show that all starless cores are significantly colder inside than outside, with central core temperatures in the range 7.5-11.9K and envelope temperatures that are 2.4-9.6K higher. The core temperatures show a strong negative correlation with peak column density which suggests that the thermal structure of the cores is dominated by external heating from the ISRF and shielding by dusty envelopes. We find that temperature profiles derived with the ray-tracing inversion method can be well-reproduced with self-consistent radiative transfer models if the cores have geometry that is not too complex and good data coverage with spatially resolved maps at five or more wavelengths in range between 100 µm and 1.2 mm. We also confirm results from earlier studies that found that the usually adopted canonical value of the total strength of the ISRF in the solar neighbourhood is incompatible with the most widely used dust opacity models for dense cores. However, with the data available for this study, we cannot uniquely resolve the degeneracy between dust opacity law and strength of the ISRF.

Abstract Copyright: © ESO 2016

Journal keyword(s): stars: formation - stars: low-mass - ISM: clouds - ISM: structure - dust, extinction - infrared: ISM

VizieR on-line data: <Available at CDS (J/A+A/592/A61): list.dat fits/*>

Simbad objects: 23

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Number of rows : 23

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2019
#notes
1 [DB2002b] G121.03-9.97 MoC 00 39 03 +52 51.5           ~ 19 0
2 [LSS2013] CB 4-SMM cor 00 39 05.2 +52 51 47           ~ 2 0
3 ACO 426 ClG 03 19 47.2 +41 30 47           ~ 1882 1
4 [LNW2010] CB 17-SMM smm 04 04 37.7 +56 55 59           ~ 7 0
5 LDN 1389 MoC 04 04 38 +56 56.2           ~ 78 0
6 LDN 1495 DNe 04 18.1 +27 37           ~ 274 1
7 NAME Auriga reg 04 20 00.0 +38 05 00           ~ 163 0
8 NAME Tau-Aur Region SFR 04 30 +25.0           ~ 1180 1
9 NAME Taurus Dark Cloud SFR 04 41.0 +25 52           ~ 3308 0
10 LDN 1439 DNe 05 00 09 +52 04.9           ~ 76 0
11 [LSS2013] CB 26-SMM2 cor 05 00 14.5 +52 05 59           ~ 2 0
12 [LSS2013] CB 27-SMM cor 05 04 08.1 +32 43 30           ~ 3 0
13 LDN 1512 MoC 05 04 09.7 +32 43 09           ~ 159 0
14 LDN 183 MoC 15 54 12.2 -02 49 42           ~ 674 1
15 NAME Ophiuchus Molecular Cloud SFR 16 28 06 -24 32.5           ~ 2929 0
16 LDN 57 DNe 17 22 38.2 -23 49 34           ~ 276 1
17 NAME the Pipe Nebula DNe 17 30 -25.0           ~ 317 1
18 NAME Cas A SNR 23 23 24.000 +58 48 54.00           ~ 2336 1
19 [LNW2010] CB 244-SMM2 smm 23 25 26.8 +74 18 22           ~ 4 0
20 LDN 1262 MoC 23 25 47 +74 17.6           ~ 130 0
21 [LNW2010] CB 244-SMM1 smm 23 25 47.3 +74 17 44           ~ 3 0
22 NAME Cep Flare MoC 23 34 +72.0           ~ 96 0
23 NAME Gould Belt PoG ~ ~           ~ 684 1

    Equat.    Gal    SGal    Ecl

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2019.10.19-07:46:55

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