Related papers: A Pre-Protostellar Core in L1551

We present observations of continuum and molecular lines towards the protostar candidates IRAS 21307+5049 and IRAS 22172+5549. Single-dish maps in the 12CO(2--1), C18O(2--1), HCO+(1--0) lines and sub-mm continuum are compared with…

We present ALMA sub-arcsecond-resolution observations of both continuum and molecular lines at 345 GHz towards the massive star-forming region IRAS 16351-4722 (hereafter I16351). A total of 12 dust cores were detected based on high spatial…

We present in this paper the results of high spectral resolution ($R$=88,100) spectroscopy at 4.7 $\mu$m with iSHELL/IRTF of hot molecular gas close to the massive binary protostar W3 IRS5. The binary was spatially resolved and the spectra…

Dense cores in massive, parsec-scale molecular clumps are sites that harbor protocluster formation. We present results from observations towards a hub-filament structure of a massive Infrared Dark Cloud (IRDC) G14.225-0.506 using the…

Using ISOPHOT maps at 100 and 200um and raster scans at 100, 120, 150 and 200um we have detected four unresolved far-infrared sources in the high latitude molecular cloud L183. Two of the sources are identified with 1.3mm continuum sources…

We report molecular line observations, made with ASTE and SEST, and dust continuum observations at 0.87 mm, made with APEX, towards the cold dust core G305.136+0.068. The molecular observations show that the core is isolated and roughly…

Although frequently reported in observations, the definitive confirmation of high-mass prestellar cores has remained elusive, presenting a persistent challenge in star formation studies. Using two-band observational data from the 3mm ATOMS…

Herschel/HIFI observations toward the compact HII region W51 has revealed the presence of a cold dense core along its line of sight in a high-velocity stream located just in front of W51. This detection has been made possible through…

We present Herschel SPIRE-FTS intermediate-sampled mapping observations of the central ~8 kpc (~150") of M51, with a spatial resolution of 40". We detect 4 12CO transitions (J=4-3 to J=7-6) and the CI 3P2-3P1 and 3P1-3P0 transitions. We…

To characterize the initial conditions for intermediate- to high-mass star formation, we observed two Infrared Dark Clouds (IRDCs) that remain absorption features up to 70mum wavelength, with the PdBI in the 3.23mm dust continuum as well as…

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…

We study the molecular and the ionized gas in a possible precursor of an UC HII region to contribute to the understanding of how high-mass stars build-up their masses once they have reached the zero-age main secuence. We carried out…

Aims: Our goal is to set constraints on the evolutionary state of the dense core Cha-MMS1 in the Chamaeleon I molecular cloud. Methods: We analyze molecular line observations carried out with the new submillimeter telescope APEX. We look…

The results of a detailed analysis of SMA, VLA, and IRAM observations of the region of massive star formation S255N in CO(2---1), \nh, \nhh, \co and some other lines is presented. Combining interferometer and single-dish data has enabled a…

Star formation in the central molecular zone (CMZ) is suppressed with respect to that of the Galactic disk, and this is likely related to its high turbulent environment. This turbulence impedes the potential detection of prestellar cores.…

We observed high S/N, high velocity resolution NH$_3$(1,1) and (2,2) emission on an extended map in TMC-1, a filamentary cloud in a nearby quiescent star forming area. By fitting multiple hyperfine-split line profiles to the NH$_3$(1,1)…

We have modeled the emission from dust in pre-protostellar cores, including a self-consistent calculation of the temperature distribution for each input density distribution. Model density distributions include Bonnor-Ebert spheres and…

We present C18O observations of the pre-stellar core L1689B, in the (J=3-2) and (J=2-1) rotational transitions, taken at the James Clerk Maxwell Telescope in Hawaii. We use a lambda-iteration radiative transfer code to model the data. We…

We present the dynamical properties of 294 cores embedded in twelve IRDCs observed as part of the ASHES Survey. Protostellar cores have higher gas masses, surface densities, column densities, and volume densities than prestellar cores,…

We develop a self-consistent model for the equilibrium gas temperature and size-dependent dust temperature in cold, dense pre-stellar cores, assuming an arbitrary power-law size distribution of dust grains. Compact analytical expressions…