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相关论文: Gas phase Elemental abundances in Molecular cloudS…

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Gas phase Elemental abundances in molecular CloudS (GEMS) is an IRAM 30m large program aimed at determining the elemental abundances of carbon (C), oxygen (O), nitrogen (N), and sulfur (S) in a selected set of prototypical star-forming…

GEMS is an IRAM 30m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dark cloud TMC 1.…

(Abridged) We explore the chemistry of the most abundant C, O, S, and N bearing species in molecular clouds, in the context of the IRAM 30 m Large Programme Gas phase Elemental abundances in Molecular Clouds (GEMS). In this work, we aim to…

Methanol, one of the simplest complex organic molecules in the Interstellar Medium (ISM), has been shown to be present and extended in cold environments such as starless cores. We aim at studying methanol emission across several starless…

Sulphur is one of the most abundant elements in the Universe. Surprisingly, sulphuretted molecules are not as abundant as expected in the interstellar medium, and the identity of the main sulphur reservoir is still an open question. Our…

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…

高能天体物理现象 · 物理学 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

CS is among the most abundant gas-phase S-bearing molecules in cold dark molecular clouds. It is easily observable with several transitions in the millimeter wavelength range, and has been widely used as a tracer of the gas density in the…

Isotopic ratios have been used as chemical diagnostics to investigate the origin of the material in the Solar System. We have determined the HCN, HNC, and N2H+ isotopic ratios and the chemical age in a large sample of 23 starless cores…

We present an analysis of elemental abundances of He, N, O, Ne, S, and Ar in Magellanic Cloud planetary nebulae (PNe), and focus initially on 14 PNe in the Small Magellanic Cloud (SMC). We derived the abundances from a combination of deep,…

Seven isolated, nearby low-mass starless molecular cloud cores have been observed as part of the Herschel key program Earliest Phases of Star formation (EPoS). By applying a ray-tracing technique to the obtained continuum emission and…

We present the first observations of H$^{13}$CN$(1-0)$, H$^{13}$CO$^+(1-0)$ and SiO$(2-1)$ in NGC\,6240, obtained with the IRAM PdBI. Combining a Markov Chain Monte Carlo (MCMC) code with Large Velocity Gradient (LVG) modelling, and with…

星系天体物理 · 物理学 2015-12-23 R. Tunnard , T. R. Greve , S. Garcia-Burillo , J. Graciá Carpio , A. Fuente , L. Tacconi , R. Neri , A. Usero

We present a systematic study of the HNCO, C18O, 13CS, and C34S emission towards 13 selected molecular clouds in the Galactic center region. The molecular emission in these positions are used as templates of the different physical and…

天体物理学 · 物理学 2009-11-13 S. Martin , M. A. Requena-Torres , J. Martin-Pintado , R. Mauersberger

We model the temperature and chemical structure of molecular clouds as a function of depth into the cloud, assuming a cloud of constant density n illuminated by an external FUV (6 eV < E < 13.6 eV) flux G_0 (scaling factor in multiples of…

天体物理学 · 物理学 2011-02-11 David Hollenbach , Michael J. Kaufman , Edwin A. Bergin , Gary J. Melnick

Aims. The Chemical Evolution of R-process Elements in Stars (CERES) project aims to provide a homogeneous analysis of a sample of metal-poor stars ([Fe/H]<-1.5). We present the stellar parameters and the chemical abundances of elements up…

In order to investigate the physical and chemical properties of massive star forming cores in early stages, we analyse the excitation and abundance of four organic species, CH3OH, CH3OCH3, HCOOCH3 and CH3CH2CN, toward 29 Extended Green…

太阳与恒星天体物理 · 物理学 2015-06-22 Jixing Ge , Jinhua He , Xi Chen , S. Takahashi

Elements in the interstellar medium (ISM) exist in the form of gas or dust. The interstellar extinction and elemental abundances provide crucial constraints on the composition, size and quantity of interstellar dust. Most of the extinction…

星系天体物理 · 物理学 2021-03-17 W. B. Zuo , Aigen Li , Gang Zhao

The study of multiple molecular spectral lines in gas infalling sources can provide the physical and chemical properties of these sources and help us estimate their evolutionary stages. We report line detections within the 3 mm band using…

星系天体物理 · 物理学 2025-04-09 Yang Yang , Xi Chen , ZhiBo Jiang , Zhiwei Chen , Shuling Yu , Jun Li

We present data on the gas phase abundances for 9 different elements in the interstellar medium of the Small Magellanic Cloud (SMC), based on the strengths of ultraviolet absorption features over relevant velocities in the spectra of 18…

星系天体物理 · 物理学 2017-05-09 Edward B. Jenkins , George Wallerstein

This paper presents the first substantial study of the chemistry of the envelopes around a sample of 18 low-mass pre- and protostellar objects for which physical properties have previously been derived from radiative transfer modeling of…

天体物理学 · 物理学 2009-11-10 J. K. Jorgensen , F. L. Schoeier , E. F. van Dishoeck
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