English
Related papers

Related papers: Non-Thermal Chemistry in Diffuse Clouds with Low M…

200 papers

An accurate treatment of the multiphase interstellar medium (ISM) in hydrodynamic galaxy simulations requires that we follow not only the thermal evolution of the gas, but also the evolution of its chemical state, including its molecular…

Astrophysics of Galaxies · Physics 2015-06-18 Alexander J. Richings , Joop Schaye , Benjamin D. Oppenheimer

Cold cores are an early step of star formation, characterized by densities > 10$^4$ cm$^{-3}$, low temperatures (< 15 K), and very low external UV radiation. We investigate the physico-chemical processes at play to tracing the origin of…

Astrophysics of Galaxies · Physics 2023-01-04 A. Taillard , V. WakelaM , P. Gratier , E. Dartois , M. Chabot , J. A. Noble , J. V. Keane , A. C. A. Boogert , D. Harsono

Ices imprint strong absorption features in the near- and mid-infrared, but until recently they have been studied almost exclusively with spectroscopy toward small samples of bright sources. We show that JWST photometry alone can reveal and…

We report high-sensitivity millimetre observations of several molecular species (13CO, HCN, HNC, CN, HCO+ and N2H+) in a sample of compact planetary nebulae. Some species such as HCO+ and CN are particularly abundant compared to envelopes…

Astrophysics · Physics 2009-11-07 E. Josselin , R. Bachiller

We present spectroscopic observations of the runaway reddened star HD 34078 acquired during the last three years at Observatoire de Haute Provence and McDonald Observatory as well as other spectra obtained since 1990. The drift of the line…

Astrophysics · Physics 2009-11-07 E. Rollinde , P. Boisse , S. R. Federman , K. Pan

Starless molecular cores are natural laboratories for interstellar molecular chemistry research. The chemistry of ices in such objects was investigated with a three-phase (gas, surface, and mantle) model. We considered the center part of…

Astrophysics of Galaxies · Physics 2015-04-24 Juris Kalvans

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…

Solar and Stellar Astrophysics · Physics 2014-10-15 Russell F. Shipman , Floris F. S van der Tak , Friedrich Wyrowski , Fabrice Herpin , Wilfred Frieswijk

We present high S/N measurements of the H I Ly alpha absorption line toward 16 Galactic targets which are at distances between approximately 190 and 2200 pc, all beyond the wall of the Local Bubble. We describe the models used to remove…

Astrophysics of Galaxies · Physics 2023-04-05 S. D. Friedman , P. Chayer , E. B. Jenkins , T. M. Tripp , G. M. Williger , G. Hebrard , P. Sonnentrucker

Infrared Dark Clouds are expected to harbor sources in different, very young evolutionary stages. To better characterize these differences, we observed a sample of 43 massive Infrared Dark Clouds, originally selected as candidate high-mass…

Astrophysics · Physics 2019-08-19 H. Beuther , T. K. Sridharan

Methane is one of the simplest stable molecules that is both abundant and widely distributed across space. It is thought to have partial origin from interstellar molecular clouds, which are near the beginning of the star formation cycle.…

Solar and Stellar Astrophysics · Physics 2020-04-16 D. Qasim , G. Fedoseev , K. -J. Chuang , J. He , S. Ioppolo , E. F. van Dishoeck , H. Linnartz

This paper assesses the roles of the presence of warm H2, and the increased formation rate due to the ion-neutral drift. We performed ideal MHD simulations that include the heating and cooling of the multiphase ISM, and where we treat…

A set of diffuse interstellar clouds in the inner Galaxy within a few hundred pc of the Galactic plane has been observed at an angular resolution of ~1 arcmin combining data from the NRAO Green Bank Telescope and the Very Large Array. At…

Astrophysics of Galaxies · Physics 2015-06-15 Yurii Pidopryhora , Felix J. Lockman , John M. Dickey , Michael P. Rupen

A prevailing theory for the interstellar production of complex organic molecules (COMs) involves formation on warm dust-grain surfaces, via the diffusion and reaction of radicals produced through grain-surface photodissociation of stable…

Astrophysics of Galaxies · Physics 2020-08-19 Mihwa Jin , Robin T. Garrod

Physical properties of the tiny scale structures in the cold neutral medium (CNM) of galaxies is a long-standing puzzle. Only a few lines of sights in our Galaxy have been studies with mixed results on the scale-invariant properties of such…

Astrophysics of Galaxies · Physics 2020-01-08 P. K. Vishwakarma , P. Dutta

Massive stars play an important role in shaping the structure of galaxies. Infrared dark clouds (IRDCs), with their low temperatures and high densities, have been identified as the potential birthplaces of massive stars. In order to…

Solar and Stellar Astrophysics · Physics 2015-05-20 T. Vasyunina , H. Linz , Th. Henning , I. Zinchenko , H. Beuther , M. Voronkov

We upgraded the chemical network from the UMIST Database for Astrochemistry 2006 to include isotopes such as ^{13}C and ^{18}O. This includes all corresponding isotopologues, their chemical reactions and the properly scaled reaction rate…

Astrophysics of Galaxies · Physics 2017-03-15 M. Röllig , V. Ossenkopf

It is currently assumed that infrared dark clouds (IRDCs) represent the earliest evolutionary stages of high-mass stars ($>$ 8 M$_{\odot}$). Submillimeter and millimeter-wave studies performed over the past 15 years show that IRDCs possess…

Solar and Stellar Astrophysics · Physics 2015-06-17 T. Vasyunina , A. I. Vasyunin , E. Herbst , H. Linz , M. Voronkov , T. Britton , I. Zinchenko , F. Schuller

We present the first detection in space of O-protonated carbonyl sulfide (\ch{HOCS+}), in the midst of an ultradeep molecular line survey toward the G+0.693-0.027 molecular cloud. From the observation of all $K$$_a$ = 0 transitions ranging…

We report on the detection of vinyl cyanide (CH2CHCN), cyanomethyl radical (CH2CN), methylacetylene (CH3CCH) and thioformaldehyde (H2CS) in the C-rich star IRC +10216. These species, which are all known to exist in dark clouds, are detected…

Astrophysics · Physics 2009-11-13 M. Agundez , J. P. Fonfria , J. Cernicharo , J. R. , Pardo , M. Guelin
‹ Prev 1 3 4 5 6 7 10 Next ›