Related papers: TMC-1C: an accreting starless core

Stars form in cold dense cores showing subsonic velocity dispersions. The parental molecular clouds display higher temperatures and supersonic velocity dispersions. The transition from core to cloud has been observed in velocity dispersion,…

We present high-resolution ($\sim$1000 AU) 3 mm observations with the NOrthern Extended Millimeter Array toward the DR21 South Filament, aiming to reveal its internal fragmentation and search for deeply embedded star-forming activities.…

We present interferometric observations of N2H+(1--0) in the starless, dense core L1544 in Taurus. Red-shifted self-absorption, indicative of inward motions, is found toward the center of an elongated core. The data are fit by a…

We have measured the deuterium fractionation (through the column density ratio N(N2D+)/N(N2H+)) and the CO depletion factor (ratio between expected and observed CO abundance) in a sample of 10 high-mass protostellar candidates, in order to…

Using the QUIJOTE line survey in the 32.0-50.4 GHz range, we report the discovery of the molecule CH2CCHC4H towards the prestellar cold core TMC-1 in the Taurus region. We also present a rigorous detection of CH2CCHC3N, along with its…

We are addressing the sites of isolated low mass star formation in the solar neighbourhood, i.e. small cloud cores within one kiloparsec. We aim at determining the physical parameters of the cores, i.e., temperature, volume density, column…

Exploring the structure and dynamics of cold starless clouds is necessary to understand the different steps leading to the formation of protostars. Because clouds evolve slowly, many of them must be studied in detail to pick up different…

In this paper we study the determinants of starless core temperatures in the Perseus molecular cloud. We use NH3 (1,1) and (2,2) observations to derive core temperatures (T_kin) and data from the COMPLETE Survey of Star Forming Regions and…

We present a submm study of the massive hot core G327.3-0.6 that constrains its physical parameters and environment. The APEX telescope was used to image CO and N2H+ emission, to observe lines from other molecules toward a hot and a cold…

We report Submillimeter Array dust continuum and molecular spectral line observations toward the Orion Bar photon-dominated region (PDR). The 1.2 mm continuum map reveals, for the first time, a total of 9 compact (r < 0.01pc) dust…

In dense parts of interstellar clouds (> 10^5 cm^-3), dust & gas are expected to be in thermal equilibrium, being coupled via collisions. However, previous studies have shown that the temperatures of the dust & gas may remain decoupled even…

We have carried out a survey toward the central regions of 85 starless cores in HCN J = 1-0 to study inward motions in the cores. Sixty-four cores were detected with HCN lines. The infall asymmetry in the HCN spectra is found to be more…

We carried out deep searches for CO line emission in the outer disk of M33, at R>7 kpc, and examined the dynamical conditions that can explain variations in the mass distribution of the molecular cloud throughout the disk of M33. We used…

The chemical and physical evolution of starless and pre-stellar cores are of paramount importance to understanding the process of star formation. The Taurus Molecular Cloud cores TMC 1-C and TMC 1-CP share similar initial conditions and…

We present the results of a series of observations of the near- and mid-infrared polarisation properties of the Seyfert 2 galaxy NGC1068. Our data agree well with previously published results in showing the need for a separate polarisation…

We present submillimetre observations of the J = 3-2 rotational transition of 12CO, 13CO and C18O across over 600 sq arcmin of the Perseus molecular cloud, undertaken with HARP, a new array spectrograph on the James Clerk Maxwell Telescope.…

Two consecutive rotational transitions of the long cyanopolyyne HC11N, J=39-38, and J=38-37, have been detected in the cold dust cloud TMC-1 at the frequencies expected from recent laboratory measurements by Travers et al. (1996), and at…

Massive clumps, prior to the formation of any visible protostars, are the best candidates to search for the elusive massive starless cores. In this work we investigate the dust and gas properties of massive clumps selected to be 70 micron…

Context: The nature of embedded accretion disks around forming high-mass stars is one of the missing puzzle pieces for a general understanding of the formation of the most massive and luminous stars. Methods: Using the Plateau de Bure…

We report molecular line and dust continuum observations toward the high-mass star forming region G331.5-0.1, one of the most luminous regions of massive star-formation in the Milky Way, located at the tangent region of the Norma spiral…