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Related papers: Chemical and physical small-scale structure in a p…

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The density and temperature structures of dense cores in the L1495 cloud of the Taurus star-forming region are investigated using Herschel SPIRE and PACS images in the 70 $\mu$m, 160 $\mu$m, 250 $\mu$m, 350 $\mu$m and 500 $\mu$m continuum…

We study the correlation between far-infared/submm dust emission and atomic gas column density in order to derive the properties of the high Galactic latitude, low density, Milky Way cirrus in the foreground of the Virgo cluster of…

Many questions remain regarding the properties of disks around massive prototstars. Here we present the observations of a high mass protostellar object including an elongated dust continuum structure perpendicular to the outflow.…

Astrophysics of Galaxies · Physics 2015-05-20 Cassandra Fallscheer , Henrik Beuther , Jürgen Sauter , Sebastian Wolf , Qizhou Zhang

The project Galactic Cold Cores has made Herschel observations of interstellar clouds where the Planck satellite survey has located cold and compact clumps. The sources range from starless clumps to protostellar cores. We examine 116…

The rotational transitions of carbon monoxide (CO) are the primary means of investigating the density and velocity structure of the molecular interstellar medium. Here we study the lowest four rotational transitions of CO towards…

Astrophysics · Physics 2009-10-31 James G. Ingalls , T. M. Bania , Adair P. Lane , Matthias Rumitz , Antony A. Stark

The dense cloud associated with W40, one of the nearby H II regions, has been studied in millimeter-wave molecular lines and in 1.2 mm continuum. Besides, 1280 MHz and 610 MHz interferometric observations have been done. The cloud has…

Astrophysics of Galaxies · Physics 2015-06-17 L. Pirogov , D. K. Ojha , M. Thomasson , Y. -F. Wu , I. Zinchenko

(Abridged) METHODS: We performed SMA observations at 1.3 mm with both the most extended and compact array configurations, providing sub-arcsecond and high sensitivity maps of various molecular lines, including both hot-core and outflow…

Astrophysics of Galaxies · Physics 2015-06-18 A. Sanna , R. Cesaroni , L. Moscadelli , Q. Zhang , K. M. Menten , S. Molinari , A. Caratti o Garatti , J. M. De Buizer

We found that in regions of high mass star formation the CS emission correlates well with the dust continuum emission and is therefore a good tracer of the total mass while the N$_2$H$^+$ distribution is frequently very different. This is…

We report the discovery of a massive SCUBA core with evidence of inflow and outflow motions. This core is detected by SCUBA at both 450 and 850 micro meter. Barely resolved by the telescope beam at 450 micro meter, it has a size of 10…

Astrophysics · Physics 2009-11-11 Y. Wu , M. Zhu , Y. Wei , D. Xu , Q. Zhang , J. D. Fiege

Infrared-dark high-mass clumps are among the most promising objects to study the initial conditions of the formation process of high-mass stars and rich stellar clusters. In this work, we have observed the (3-2) rotational transition of…

Astrophysics of Galaxies · Physics 2015-06-04 F. Fontani , A. Giannetti , M. T. Beltran , R. Dodson , M. Rioja , J. Brand , P. Caselli , R. Cesaroni

We recently reported a population of protostellar candidates in the 20 km s$^{-1}$ cloud in the Central Molecular Zone of the Milky Way, traced by H$_2$O masers in gravitationally bound dense cores. In this paper, we report…

We have considered the thermal equilibrium in pre-protostellar cores in the approximation where the dust temperature is independent of interactions with the gas and where the gas is heated both by collisions with dust grains and ionization…

Astrophysics · Physics 2009-11-07 D. Galli , M. Walmsley , J. Goncalves

We have mapped the starless core TMC-1C in a variety of molecular lines with the IRAM 30m telescope. High density tracers show clear signs of self-absorption and sub-sonic infall asymmetries are present in N2H+ (1-0) and DCO+ (2-1) lines.…

Astrophysics · Physics 2009-11-13 S. Schnee , P. Caselli , A. Goodman , H. G. Arce , J. Ballesteros-Paredes , K. Kuchibhotla

Starless cores represent the initial stage of evolution toward (proto)star formation, and a subset of them, known as prestellar cores, with high density (~ 10^6 cm^-3 or higher) and being centrally concentrated are expected to be embryos of…

Low-mass stars like our Sun begin their evolution within cold (10 K) and dense ($\sim 10^5$ cm$^{-3}$) cores of gas and dust. The physical structure of starless cores is best probed by thermal emission of dust grains. We present a high…

Astrophysics of Galaxies · Physics 2023-04-05 Samantha Scibelli , Yancy Shirley , Anika Schmiedeke , Brian Svoboda , Ayushi Singh , James Lilly , Paola Caselli

CONTEXT: Dense cores are thought to be isolated from the surrounding cloud. However, observations of streamers and subsonic material outside core boundaries challenges this idea. AIMS: In this study, we aim to probe the extended subsonic…

Astrophysics of Galaxies · Physics 2025-04-30 Spandan Choudhury , Jongsoo Kim , Paola Caselli , Chang Won Lee , Jaime E. Pineda

We present a 3-mm and 1.3-cm spectral line survey conducted with the Mopra 22-m and Parkes 64-m radio telescopes of a sample of 40 cold dust cores, previously observed with BLAST, including both starless and proto-stellar sources. 20…

We clarify the line-of-sight structure of the Taurus Molecular Cloud 1 (TMC-1) on the basis of the CCS($J_N=4_3-3_2$) and HC$_3$N($J=5-4$) spectral data observed at a very high velocity resolution and sensitivity of $\Delta V \simeq 0.0004$…

Astrophysics of Galaxies · Physics 2018-09-19 Kazuhito Dobashi , Tomomi Shimoikura , Fumitaka Nakamura , Seiji Kameno , Izumi Mizuno , Kotomi Taniguchi

We present ALMA follow-up observations of two massive, early-stage core candidates, C1-N & C1-S, in Infrared Dark Cloud (IRDC) G028.37+00.07, which were previously identified by their N2D+(3-2) emission and show high levels of deuteration…

Astrophysics of Galaxies · Physics 2016-04-20 Jonathan C. Tan , Shuo Kong , Yichen Zhang , Francesco Fontani , Paola Caselli , Michael J. Butler

A set of diffuse interstellar clouds in the inner Galaxy within a few hundred pc of the Galactic plane has been observed at an angular resolution of ~1 arcmin combining data from the NRAO Green Bank Telescope and the Very Large Array. At…

Astrophysics of Galaxies · Physics 2015-06-15 Yurii Pidopryhora , Felix J. Lockman , John M. Dickey , Michael P. Rupen