相关论文: The physical state of selected cold clumps
We examine the cloud structure around the Planck detections in 71 fields observed with the Herschel SPIRE instrument. We wish to determine the general physical characteristics of the fields and to examine the morphology of the clouds where…
We mapped five massive star forming regions with the SCUBA-2 camera on the James Clerk Maxwell Telescope (JCMT). Temperature and column density maps are obtained from the SCUBA-2 450 and 850 $\mu$m images. Most of the dense clumps we find…
Planck cold clumps are among the most promising objects to investigate the initial conditions of the evolution of molecular clouds. In this work, by combing the dust emission data from the survey of Planck satellite with the molecular data…
Context. The earliest phases of high-mass star formation are poorly understood. Aims. Our goal is to determine the physical conditions and kinematic structure of massive star-forming cloud clumps. Methods. We analyze H$_2$O 557 GHz line…
We present Submillimeter Array (SMA) observations of seven massive molecular clumps which are dark in the far-infrared for wavelengths up to 70 $\mu$m. Our 1.3 mm continuum images reveal 44 dense cores, with gas masses ranging from 1.4 to…
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…
We present dust column densities and dust temperatures for $\sim3000$ young high-mass molecular clumps from the Millimetre Astronomy Legacy Team 90 GHz (MALT90) survey, derived from adjusting single temperature dust emission models to the…
We present newly processed archival Herschel images of molecular cloud MCLD 123.5+24.9 in the Polaris Flare. This cloud contains five starless cores. Using the spectral synthesis code Cloudy, we explore uncertainties in the derivation of…
Gas at high Galactic latitude is a relatively little-noticed component of the interstellar medium. In an effort to address this, forty-one Planck Galactic Cold Clumps at high Galactic latitude (HGal; $|b|>25^{\circ}$) were observed in…
The Planck Catalogue of Galactic Cold Clumps (PGCC) contains over 13000 sources detected based on their cold dust signature. They are believed to consist of a mixture of quiescent, pre-stellar, and already star-forming objects. We extracted…
High mass stars form in groups or clusters within massive cores in dense molecular clumps with sizes of 1pc and masses of 200Msun which are important laboratories for high-mass star formation in order to study the initial conditions. We…
Observations of CO+ suggest column densities on the order 10^12 cm^-2 that can not be reproduced by many chemical models. CO+ is more likely to be destroyed than excited in collisions with hydrogen. An anomalous excitation mechanism may…
The chemical changes of high-mass star-forming regions provide a potential method for classifying their evolutionary stages and, ultimately, ages. In this study, we search for correlations between molecular abundances and the evolutionary…
We used FIR and submillimeter continuum data from Herschel and the Atacama Pathfinder EXperiment (APEX) to fit pixel-by-pixel modified Planck SEDs to prestellar and protostellar clumps in the Census of High- and Medium-mass Protostars…
The Planck Early Cold Cores Catalog (ECC) provides an unbiased list of Galactic cold clumps, which form an ideal sample for studying the early phases of star formation (\cite[Planck Collabrators et al. 2011]{Planck_etal11}). To study their…
We present a study of chemistry toward 294 dense cores in 12 molecular clumps using the data obtained from the ALMA Survey of 70 $\mu \rm m$ dark High-mass clumps in Early Stages (ASHES). We identified 97 protostellar cores and 197…
The results from a single-dish molecular line survey of a set of 18 deeply embedded young stellar objects are summarized. More than 40 lines from 16 different species were observed with the JCMT, Onsala, IRAM 30m and SEST telescopes. The…
We selected 90 massive star-forming clumps with strong N2H+, HCO+, HCN, and HNC emission from the Millimetre Astronomy Legacy Team 90 GHz survey. We obtained Herschel data for all 90 sources and NRAO VLA Sky Survey data for 51 of them. We…
We present molecular line observations made with the IRAM 30-m telescope of the immediate surroundings of a sample of 11 candidate high-mass protostars. These observations are part of an effort to clarify the evolutionary status of a set of…
The Herschel Gould Belt Survey key project mapped the bulk of nearby star-forming molecular clouds in five far-infrared bands with the aim of compiling complete census of prestellar cores and young, embedded protostars. In this paper, we…