Related papers: Ices in the Quiescent IC 5146 Dense Cloud

This paper presents results from modelling 450 micron and 850 micron continuum and HCO+ line observations of three distinct cores of an infrared dark cloud (IRDC) directed toward the W51 GMC. In the sub-mm continuum these cores appear as…

Normal field stars located behind dense clouds are a valuable resource in interstellar astrophysics, as they provide continua in which to study phenomena such as gas-phase and solid-state absorption features, interstellar extinction and…

Observations at submillimeter wavelengths have revealed a population of sources thought to be at relatively large redshifts. The position of the 850 $\mu$m passband on the Rayleigh-Jeans portion of the Planck function leads to a maximum…

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 52-93 micron spectra, obtained with the Spitzer Space Telescope, of luminous compact far-IR sources in the SMC. These comprise 9 Young Stellar Objects (YSOs), the compact HII region N81 and a similar object within N84, and two…

Whether ice in cold cosmic environments is physically separated from the silicate dust or mixed with individual silicate moieties is not known. However, different grain models give very different compositions and temperatures of grains. The…

We present 450 and 850 micron submillimetre continuum observations of the IC5146 star-forming region taken as part of the JCMT Gould Belt Survey. We investigate the location of bright submillimetre (clumped) emission with the larger-scale…

We present a study of the abundances and physical conditions in the interstellar gas toward the heavily reddened star HD 192639 [E_(B-V) = 0.64], based on analysis of FUSE and HST/STIS spectra covering the range from 912 to 1361 A. This…

IRAS 18511+0146 is a young embedded (proto)cluster located at 3.5 kpc surrounding what appears to be an intermediate mass protostar. In this paper, we investigate the nature of cluster members (two of which are believed to be the most…

We present the N-band (8-13 micron) spectrum of the hidden compact radio super-star cluster in NGC 5253, C2, obtained with TIMMI2 on the ESO 3.6m telescope. The spectrum is characterised by a rising continuum due to warm dust, a silicate…

Infrared (IR) spectra of vapor-deposited amorphous water at low temperatures show two weak peaks at around 3720 and 3696 cm-1 assigned to free-OH stretching modes of two- and three-coordinated water molecules (so-called dangling OH bonds),…

We report the detection of several molecular gas-phase and ice absorption features in three photometrically-selected young stellar object (YSO) candidates in the central 280 pc of the Milky Way. Our spectra, obtained with the Infrared…

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…

Progress in understanding star formation requires detailed observational constraints on the initial conditions, i.e. dense clumps and cores in giant molecular clouds that are on the verge of gravitational instability. Such structures have…

The structure and composition of simple ices can be modified during stellar evolution by protostellar heating. Key to understanding the involved processes are thermal and chemical tracers that can diagnose the history and environment of the…

Diffuse far-ultraviolet (FUV: 1370-1670 A) flux from the Taurus molecular cloud region has been observed with the SPEAR/FIMS imaging spectrograph. An FUV continuum map of the Taurus region, similar to the visual extinction maps, shows a…

We present consistent modelling of line and continuum IR spectra in the region close to the Galactic center. The models account for the coupled effect of shocks and photoionization from an external source. The results show that the shock…

Infrared-dark clouds (IRDCs) harbor the early phases of cluster and high-mass star formation and are comprised of cold (~20 K), dense (n > 10$^4$ cm$^{-3}$) gas. The spectral energy distribution (SED) of IRDCs is dominated by the…

Gaseous H2O has been detected in several cold astrophysical environments, where the observed abundances cannot be explained by thermal desorption of H2O ice or by H2O gas phase formation. These observations hence suggest an efficient…

Interstellar grain mantles present in dense interstellar clouds are in constant exchange with the gas phase via accretion and desorption mechanisms such as UV, X-ray photodesorption, cosmic ray induced sputtering, grain thermal…