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Related papers: Heavy water stratification in a low-mass protostar

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We investigate on the spatial and velocity distribution of H2O along the L1448 outflow, its relationship with other tracers, and its abundance variations, using maps of the o-H2O 1_{10}-1_{01} and 2_{12}-1_{01} transitions taken with the…

Aims: Using the unprecedented combination of high resolution and sensitivity offered by ALMA, we aim to investigate whether and how hot corinos, circumstellar disks, and ejected gas are related in young solar-mass protostars. Methods: We…

Solar and Stellar Astrophysics · Physics 2016-02-03 C. Codella , C. Ceccarelli , S. Cabrit , L. Podio , R. Bachiller , F. Fontani , A. Gusdorf , B. Lefloch , S. Leurini , M. Tafalla

Establishing the origin of the water D/H ratio in the Solar System is central to our understanding of the chemical trail of water during the star and planet formation process. Recent modeling suggests that comparisons of the D$_2$O/HDO and…

Astrophysics of Galaxies · Physics 2021-06-30 S. S. Jensen , J. K. Jørgensen , L. E. Kristensen , A. Coutens , E. F. van Dishoeck , K. Furuya , D. Harsono , M. V. Persson

Context. The deuterium fraction in low-mass prestellar cores is a good diagnostic indicator of the initial phases of star formations, and it is also a fundamental quantity to infer the ionisation degree in these objects. Aims. With the…

Solar and Stellar Astrophysics · Physics 2019-08-28 Elena Redaelli , Luca Bizzocchi , Paola Caselli , Olli Sipilä , Valerio Lattanzi , Barbara Michela Giuliano , Silvia Spezzano

Context: In the laboratory, hydrogen peroxide (HOOH) was proven to be an intermediate product in the solid-state reaction scheme that leads to the formation of water on icy dust grains. When HOOH desorbs from the icy grains, it can be…

Solar and Stellar Astrophysics · Physics 2020-04-29 G. W. Fuchs , D. Witsch , D. Herberth , M. Kempkes , B. Stanclik , J. Chantzos , H. Linnartz , K. Menten , T. F. Giesen

The structure in density and temperature of protoplanetary disks surrounding low-mass stars is not yet well known. The protoplanetary disks mid-planes are expected to be very cold and thus depleted in molecules in gas phase, especially CO.…

Astrophysics of Galaxies · Physics 2017-11-29 E. Chapillon , B. Parise , S. Guilloteau , F. Du

We have analyzed rotational spectral line emission of OCS, CH3OH, HCOOCH3, and H2CS observed toward the low-mass Class 0 protostellar source IRAS 16293-2422 Source A at a sub-arcsecond resolution (~0".6 x 0".5) with ALMA. Significant…

We have modeled the emission of H2O rotational lines from the extreme C-rich star IRC+10216. Our treatment of the excitation of H2O emissions takes into account the excitation of H2O both through collisions, and through the pumping of the…

Astrophysics · Physics 2009-11-13 Eduardo González-Alfonso , David A. Neufeld , Gary J. Melnick

We present deep Herschel-PACS spectroscopy of far-infrared water lines from a sample of four protoplanetary disks around solar-mass stars, selected to have strong water emission at mid-infrared wavelengths. By combining the new Herschel…

The study of deuterium fractionation is a valuable tool for reconstructing our chemical history from the early prestellar stages to the formation of planets. In the context of the ALMA Large Programme FAUST, we observed formaldehyde,…

This paper reviews the first results of observations of H2O line emission with Herschel-HIFI towards high-mass star-forming regions, obtained within the WISH guaranteed time program. The data reveal three kinds of gas-phase H2O: `cloud…

Astrophysics of Galaxies · Physics 2019-08-14 Floris van der Tak , Fabrice Herpin , Friedrich Wyrowski

Deuterium fractionation is highly efficient during the early stages of star formation, particularly in starless and prestellar cores where temperatures are low (<10 K) and molecular freeze-out onto dust grains is significant. Methanol forms…

We present observations of the ground state 1$_{0,1}$-0$_{0,0}$ rotational transition of HDO at 464.925 GHz and the 1$_{1,0}$-1$_{0,1}$ transition at 509.292 GHz toward the three high-mass star forming regions: G34.26+0.15, W49N, and…

Astrophysics of Galaxies · Physics 2017-03-01 Magda Kulczak-Jastrzȩbska

How protostars accrete mass is one of the fundamental problems of star formation. High column densities and complex kinematical structures make direct observations challenging and they only provide a snapshot. Chemical tracers provide an…

Observations of deuterium fractionation in the solar system, and in interstellar and circumstellar material, are commonly used to constrain the formation environment of volatiles. Toward protoplanetary disks, this approach has been limited…

Solar and Stellar Astrophysics · Physics 2015-08-26 Jane Huang , Karin Oberg

We present observations of CO, 13CO and of H2O in the middle and far-infrared taken with the ISO-SWS and ISO-LWS spectrometers toward two positions in the Galactic Center region (Sgr A* and GCS-3). Both ice and gas phase molecules are…

Astrophysics · Physics 2009-10-31 Andrea Moneti , Jose Cernicharo , Juan Ramon Pardo

We present Herschel/HIFI observations of nine transitions of \hho and \hheo towards six high-mass star-forming regions, obtained as part of the PRISMAS Key Program. Water vapor in translucent clouds is detected in absorption along every…

OH is an important molecule in the H2O chemistry and the cooling budget of star-forming regions. The goal of the Herschel key program `Water in Star-forming regions with Herschel' (WISH) is to study H2O and related species during…

Spitzer-IRS maps of H_2 pure rotational lines from S(0) to S(7) in 3 outflows from Class 0 sources - L1448, BHR71, and NGC2071 - are presented. These lines are used, in conjunction with available rovibrational, near-IR H_2 lines, to probe…

Solar and Stellar Astrophysics · Physics 2015-05-28 T. Giannini , B. Nisini , D. Neufeld , Y. Yuan , S. Antoniucci , A. Gusdorf

Space-based mid-IR spectroscopy provides tracers of warm gas in star-forming regions that are inaccessible from the ground. Past mid-IR spectra of bright high-mass protostars in the hot-core phase typically showed strong absorption features…

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