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Related papers: Gas phase Elemental abundances in Molecular cloudS…

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We investigated the chemistry of nitrogen--containing species, principally isotopomers of CN, HCN, and HNC, in a sample of pre-protostellar cores. We used the IRAM 30 m telescope to measure the emission in rotational and hyperfine…

Solar and Stellar Astrophysics · Physics 2015-05-18 Pierre Hily-Blant , Malcolm Walmsley , G. Pineau Des forêts , David Flower

The density of cosmic rays inside molecular clouds determines the ionization rate in the dense cores where stars form. It is also one of the drivers of astrochemistry leading to the creation of complex molecules. Through Fermi Large Area…

High Energy Astrophysical Phenomena · Physics 2023-01-18 Rui-zhi Yang , Guang-Xing Li , Emma de Oña Wilhelmi , Yu-Dong Cui , Bing Liu , Felix Aharonian

Observations of various molecular lines toward a disk region of a nearby galaxy are now feasible, and they are being employed as diagnostic tools to study star-formation activities there. However, the spatial resolution attainable for a…

Astrophysics of Galaxies · Physics 2019-07-17 Yuri Nishimura , Yoshimasa Watanabe , Nanase Harada , Kotaro Kohno , Satoshi Yamamoto

Many questions in physical cosmology regarding the thermal history of the intergalactic medium, chemical enrichment, reionization, etc. are thought to be intimately related to the nature and evolution of pregalactic structure. In particular…

Astrophysics · Physics 2009-10-31 Tom Abel , Greg L. Bryan , Michael L. Norman

A magnetohydrodynamic model of a steady, transverse C-type shock in a dense molecular cloud is presented. A complete gas-grain chemical network is taken into account: the gas-phase chemistry, the adsorption of gas species on dust grains,…

Astrophysics of Galaxies · Physics 2018-06-12 A. V. Nesterenok

The total disk gas mass and elemental C, N, O composition of protoplanetary disks are crucial ingredients for our understanding of planet formation. Measuring the gas mass is complicated, since H$_2$ cannot be detected in the cold bulk of…

Earth and Planetary Astrophysics · Physics 2023-02-08 J. A. Sturm , A. S. Booth , M. K. McClure , M. Leemker , E. F. van Dishoeck

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

The [CII] fine--structure line at 158um is an excellent tracer of the warm diffuse gas in the ISM and the interfaces between molecular clouds and their surrounding atomic and ionized envelopes. Here we present the initial results from…

We present an analysis of gas densities in the central R=300 parsecs of the Milky Way, focusing on three clouds: GCM-0.02-0.07 (the 50 km/s cloud), GCM-0.13-0.08 (the 20 km/s cloud), and GCM0.25+0.01 (the "Brick"). Densities are determined…

Astrophysics of Galaxies · Physics 2018-11-28 E. A. C. Mills , A. Ginsburg , K. Immer , J. M Barnes , L. Wiesenfeld , A. Faure , M. R. Morris , M. A. Requena-Torres

We study the molecular gas content of 24 star-forming galaxies at $z=3-4$, with a median stellar mass of $10^{9.1}$ M$_{\odot}$, from the MUSE Hubble Ultra Deep Field (HUDF) Survey. Selected by their Lyman-alpha-emission and H-band…

Chemical abundances in the X-ray halos (also known as the intracluster medium, ICM) of clusters and groups of galaxies can be measured via prominent emission line features in their X-ray spectra. Elemental abundances are footprints of…

High Energy Astrophysical Phenomena · Physics 2018-12-19 Junjie Mao , J. de Plaa , J. S. Kaastra , Ciro Pinto , Liyi Gu , F. Mernier , Hong-Liang Yan , Yu-Ying Zhang , H. Akamatsu

We present an extragalactic survey using observations from the Atacama Large Millimeter/submillimeter Array (ALMA) to characterise galaxy populations up to $z=0.35$: the Valpara\'iso ALMA Line Emission Survey (VALES). We use ALMA Band-3…

Using IRAM 30m, SEST 15m, and Nancay radiotelescopes, we have gathered the 1mm continuum emission, spectra of the J=1--0 CO line and of the HI line at 21cm for two samples of IRAS galaxies. Using these data, we have estimated the HI masses,…

Astrophysics · Physics 2016-08-30 Paola Andreani , Fabienne Casoli , Maryvonne Gerin

UV observations with Cassini ISS Narrow Angle Camera of Titan's detached haze is an excellent tool to probe its aerosols content without being affected by the gas or the multiple scattering. Unfortunately, its low extent in altitude…

Earth and Planetary Astrophysics · Physics 2017-04-05 Benoît Seignovert , Pascal Rannou , Panayotis Lavvas , Thibaud Cours , Robert A. West

We present Early Science observations with the Large Millimeter Telescope, AzTEC 1.1 mm continuum images and wide bandwidth spectra (73-111 GHz) acquired with the Redshift Search Receiver, towards four bright lensed submillimetre galaxies…

Sulphur-bearing species are often used to probe the physical structure of star forming regions of the interstellar medium, but the chemistry of sulphur in these regions is still poorly understood. In dark clouds, sulphur is supposed to be…

Atomic fine structure lines have been detected in the local Universe and at high redshifts over the past decades. The [C II] emission line at 158 $\mu$m is an important observable as it provides constraints on the interstellar medium (ISM)…

Astrophysics of Galaxies · Physics 2021-01-27 Andrés Felipe Ramos Padilla , Lingyu Wang , Sylvia Ploeckinger , F. F. S. van der Tak , Scott Trager

We recently reported a population of protostellar candidates in the 20 km s$^{-1}$ cloud in the Central Molecular Zone of the Milky Way, traced by H$_2$O masers in gravitationally bound dense cores. In this paper, we report…

New observations of 11 compact galaxies in the 12CO J=2-1 and J=3-2 transitions and literature data have been used to construct accurate line ratios in matched beams allowing LVG modelling of physical parameters. Fitting a single gas…

Astrophysics · Physics 2009-11-11 F. P. Israel

We find that clouds of optically-thin, pressure-confined gas are prone to fragmentation as they cool below $\sim10^6$ K. This fragmentation follows the lengthscale $\sim{c}_{\text{s}}\,t_{\text{cool}}$, ultimately reaching very small scales…

Astrophysics of Galaxies · Physics 2018-05-10 Michael McCourt , S. Peng Oh , Ryan M. O'Leary , Ann-Marie Madigan
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