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Related papers: Methanol Mapping in Cold Cores: Testing Model Pred…

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The results of interferometric observations of the star-forming region S255IR in the frequency range 210--250 GHz are presented. The observations were carried out with the antenna array SMA (Hawaii, USA). Fifty-three molecules were…

Astrophysics of Galaxies · Physics 2026-02-17 E. A. Mikheeva , S. V. Kalenskii , S. -Y. Liu , A. M. Sobolev , S. Kurtz

Methanol masers are often detected in regions of intense star formation. Several studies in the last decade indicate that they may even be the earliest signpost of a high-mass star-forming region. Their powerful emission make them very good…

Astrophysics · Physics 2009-11-10 M. Pestalozzi , V. Minier , R. Booth

In regions where stars form, variations in density and temperature can cause gas to freeze-out onto dust grains forming ice mantles, which influences the chemical composition of a cloud. The aim of this paper is to understand in detail the…

Solar and Stellar Astrophysics · Physics 2017-11-08 S. Cazaux , R. Martin-Domenech , Y. J. Chen , G. M. Munoz Caro , C. Gonzalez Diaz

We have recently completed an observing program with the Australia Telescope Compact Array towards massive star formation regions traced by 6.7 GHz methanol maser emission. We found the molecular cores could be separated into groups based…

Astrophysics · Physics 2007-11-29 S. N. Longmore , M. G. Burton , C. R. Purcell , P. Barnes , J. Ott

Observations of Neptune, made in 2018 using the new Narrow Field Adaptive Optics mode of the Multi Unit Spectroscopic Explorer (MUSE) instrument at the Very Large Telescope (VLT) from 0.48 - 0.93 micron, are analysed here to determine the…

The observational counterparts of theoretically predicted first hydrostatic cores (FHSC) have been searched for in the interstellar medium for nearly two decades now. Distinguishing them from other types of more evolved but still embedded…

Astrophysics of Galaxies · Physics 2022-11-09 V. Wakelam , A. Coutens , P. Gratier , T. H G Vidal , N. Vaytet

Methanol masers which are traditionally divided into two classes provide possibility to study important parts of the star forming regions: Class~II masers trace vicinities of the massive YSOs while class~I masers are likely to trace more…

Cold ($\sim$10 K) and dense ($\sim$10$^{5}$ cm$^{-3}$) cores of gas and dust within molecular clouds, known as starless and dynamically evolved prestellar cores, are the birthplaces of low-mass ($M$ $\leq$ few M$_\odot$) stars. As…

Astrophysics of Galaxies · Physics 2024-08-22 Samantha Scibelli , Yancy Shirley , Andrés Megías , Izaskun Jiménez-Serra

Intriguing work on observations of 4.83 GHz formaldehyde (H2CO) absorptions and 4.87 GHz H110a radio recombination lines (RRLs) towards 6.7 GHz methanol (CH3OH) maser sources is presented. Methanol masers provide ideal sites to probe the…

Solar and Stellar Astrophysics · Physics 2015-06-18 Daniel. Okoh , Jarken. Esimbek , Jian. Jun. Zhou , Xin. Di. Tang , Augustine. Chukwude , Johnson. Urama , Pius. Okeke

We report a detection in the interstellar medium of an infrared transition within the electronic ground state of the deuterated hydrogen molecule, HD. Through a deep integration with the Short-Wavelength-Spectrometer on ISO, the pure…

We report total abundances and related parameters for the full sample of the FUSE survey of molecular hydrogen in 38 translucent lines of sight. New results are presented for the "second half" of the survey involving 15 lines of sight to…

Methanol (CH$_3$OH) is at the root of organic ice chemistry in protoplanetary disks. However, its weak emission has made detections difficult. To date, gas-phase CH$_3$OH has been detected in only one Class II disk, TW Hya. We use the…

Solar and Stellar Astrophysics · Physics 2019-03-20 M. T. Carney , M. R. Hogerheijde , V. V. Guzmán , C. Walsh , K. I. Öberg , E. C. Fayolle , L. I. Cleeves , J. M. Carpenter , C. Qi

Molecular segregation in methanol-water mixtures is studied across a wide concentration range as a function of temperature and pressure. Cluster distributions obtained from both neutron diffraction and molecular dynamics simulations point…

Soft Condensed Matter · Physics 2009-11-10 L. Dougan , R. Hargreaves , S. P. Bates , J. L. Finney , V. Reat , A. K. Soper , J. Crain

Despite the organic molecule inventory detected in Orion KL, acetaldehyde (CH3CHO) -- one of the most ubiquitous interstellar aldehydes -- has not been firmly identified with mm-wave interferometry. We analyze extensive ALMA archival…

We observe 84 candidate young high-mass sources in the rare isotopologues C17O and C18O to investigate whether there is evidence for depletion (freeze-out) towards these objects. Observations of the J=2-1 transitions of C18O and C17O are…

Astrophysics · Physics 2009-11-13 H. S. Thomas , G. A. Fuller

The aim of the presented work is to analyze the impact of experimentally evaluated reactions of hydrogen abstraction on surfaces of interstellar grains on the chemical evolution of methanol and its precursors on grains and in the gas phase…

Astrophysics of Galaxies · Physics 2021-03-24 V. A. Sokolova

We investigate which structures the 6.7 GHz methanol masers trace in the environment of high-mass protostar candidates by observing a homogenous sample of methanol masers selected from Torun surveys. We also probed their origins by looking…

Astrophysics of Galaxies · Physics 2015-05-13 A. Bartkiewicz , M. Szymczak , H. J. van Langevelde , A. M. S. Richards , Y. M. Pihlstrom

Under cold conditions in dense cores, gas-phase molecules and atoms are depleted from the gas-phase to the surface of interstellar grains. Considering the time scales and physical conditions within these cores, a portion of these molecules…

Astrophysics of Galaxies · Physics 2021-08-11 V. Wakelam , E. Dartois , M. Chabot , S. Spezzano , D. Navarro-Almaida , J. -C. Loison , A. Fuente

The 6.7 GHz maser transition of methanol has been found exclusively towards massive star forming regions. A majority of the masers have been found to lack the presence of any associated radio continuum. This could be due to the maser…

Astrophysics of Galaxies · Physics 2015-05-19 J. D. Pandian , E. Momjian , Y. Xu , K. M. Menten , P. F. Goldsmith

Deuterium fractionation is known to enhance the [DCO+]/[HCO+] abundance ratio over the D/H elemental ratio of about 1e-5 in the cold and dense gas typically found in pre-stellar cores. We report the first detection and mapping of very…