Related papers: Heavy water stratification in a low-mass protostar
Prestellar cores represent early sites of low-mass ($M$ $\leq$ few M$_\odot$) star and planet formation and provide insight into initial chemical conditions of complex organic molecules (COMs). Deuterated COMs trace the degree of molecular…
(Abridged) We present Herschel/HIFI spectra of the H2O 1113 GHz and H2O+ 1115 GHz lines toward five nearby prototypical starburst/AGN systems, and OH+ 971 GHz spectra toward three of these. The beam size of 20" corresponds to resolutions…
Early results from the Herschel Space Observatory revealed the water cation H2O+ to be an abundant ingredient of the interstellar medium. Here we present new observations of the H2O and H2O+ lines at 1113.3 and 1115.2 GHz using the Herschel…
Water is present during all stages of star formation: as ice in the cold outer parts of protostellar envelopes and dense inner regions of circumstellar disks, and as gas in the envelopes close to the protostars, in the upper layers of…
Water and methanol are key components of interstellar ices and gas in star- and planet-forming regions, but direct observations of water in low-mass protostars are challenging due to atmospheric absorption. We present high-resolution (R =…
We report the first detection outside of the solar system of the lowest pure rotational J=1-0 transition of the HD molecule at 112 microns. The detection was made toward the Orion Bar using the Fabry-Perot of the Long Wavelength…
We present the detection and characterization of a peculiar low-mass protostar (IRAS 22129+7000) located ~0.4 pc from Ced 201 Photodissociation Region (PDR) and ~0.2 pc from the HH450 jet. The cold circumstellar envelope surrounding the…
We present Herschel/HIFI observations of 30 transitions of water isotopologues toward the high-mass star forming region NGC 6334 I. The line profiles of H_2^{16}O, H_2^{17}O, H_2^{18}O, and HDO show a complex pattern of emission and…
We present the modeling results of deuterium fractionation of water ice, H2, and the primary deuterium isotopologues of H3+ adopting physical conditions associated with the star and planet formation process. We calculated the deuterium…
According to traditional gas-phase chemical models, O2 should be abundant in molecular clouds, but until recently, attempts to detect interstellar O2 line emission with ground- and space-based observatories have failed. Following the…
Our present understanding of high-mass star formation still remains very schematic. In particular, it is not yet clear how much of the difference between low-mass and high-mass star formation occurs during the earliest star formation…
A fundamental question about the early evolution of low-mass protostars is when circumstellar disks may form. High angular resolution observations of molecular transitions in the (sub)millimeter wavelength windows make it possible to…
(Abridged) Mid- and far-infrared observations of the environment around embedded protostars reveal a plethora of high excitation molecular and atomic emission lines. In this work we present spectro-imaging observations of the HH211 system…
Ions and electrons play an important role in various stages of the star formation process. By following the magnetic field of their environment and interacting with neutral species, they slow down the gravitational collapse of the…
We aim at characterizing the large-scale distribution of H2O in G327.3-0.6, a massive star-forming region made of individual objects in different evolutionary phases. We investigate variations of H2O abundance as function of evolution. We…
Deuterium fractionation can constrain the physical and chemical conditions at the early stage of brown dwarf formation. We present IRAM 30m observations over a wide frequency range of 213-279 GHz of singly and doubly deuterated species of…
We present Herschel observations of the water molecule in the massive star-forming region W3 IRS5. The o-H17O 110-101, p-H18O 111-000, p-H2O 22 202-111, p-H2O 111-000, o-H2O 221-212, and o-H2O 212-101 lines, covering a frequency range from…
We report an extensive rotational spectroscopic analysis of singly deuterated methyl mercaptan (CH$_{2}$DSH) using both millimeter and far-infrared synchrotron spectra to achieve a global torsional analysis of the three lowest torsional…
[Abridged] The majority of stars form in binary or higher order systems. The Class 0 protostellar system IRAS16293-2422 contains two protostars, 'A' and 'B', separated by ~600 au and embedded in a single, 10^4 au scale envelope. Their…
In the context of the ASAI (Astrochemical Surveys At IRAM) project, we carried out an unbiased spectral survey in the millimeter window towards the well known low-mass Class I source SVS13-A. The high sensitivity reached (3-12 mK) allowed…