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相关论文: CH$_3$CN deuteration in the SVS13-A Class I hot-co…

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In observational studies of infrared dark clouds, the number of detections of CO freeze-out onto dust grains (CO depletion) at pc-scale is extremely limited, and the conditions for its occurrence are, therefore, still unknown. We report a…

(Abridged) We aim to determine the degrees of CO depletion, deuterium fractionation, and ionisation in a sample of seven massive clumps associated with IRDCs. The APEX telescope was used to observe the C17O(2-1), H13CO+(3-2), DCO+(3-2),…

星系天体物理 · 物理学 2015-05-30 Oskari Miettinen , Martin Hennemann , Hendrik Linz

The abundances of deuterated molecules with respect to their main isotopologue counterparts have been determined to be orders of magnitude higher than expected from the cosmic abundance of deuterium relative to hydrogen. The increasing…

星系天体物理 · 物理学 2023-03-01 J. Ferrer Asensio , S. Spezzano , L. H. Coudert , V. Lattanzi , C. P. Endres , J. K. Jørgensen , P. Caselli

We study molecular emission in a massive condensation at the border of the HII region RCW 120, paying particular attention to the Core 1 and Core 2 objects, the most massive fragments of the condensation found previously by ALMA. The latter…

星系天体物理 · 物理学 2021-03-03 M. S. Kirsanova , S. V. Salii , S. V. Kalenskii , D. S. Wiebe , A. M. Sobolev , P. A. Boley

To understand massive star formation requires study of its initial conditions. Two massive starless core candidates, C1-N & C1-S, have been detected in IRDC G028.37+00.07 in $\rm N_2D^+$(3-2) with $ALMA$. From their line widths, either the…

星系天体物理 · 物理学 2016-06-01 Shuo Kong , Jonathan C. Tan , Paola Caselli , Francesco Fontani

In the search for the building blocks of life, nitrogen-bearing molecules are of particular interest since nitrogen-containing bonds are essential for the linking of amino acids and ultimately the formation of larger biological structures.…

太阳与恒星天体物理 · 物理学 2019-04-17 E. G. Bøgelund , B. A. McGuire , M. R. Hogerheijde , E. F. van Dishoeck , N. F. W. Ligterink

The present survey represents a continuation of our study of high mass star forming regions in the lines of deuterated molecules, the first results of which were published in Trofimova et al. (2020). This paper presents the results of…

星系天体物理 · 物理学 2024-09-17 E. Trofimova , I. Zinchenko , P. Zemlyanukha , M. Thomasson

Recent measurements of carbon isotope ratios in both protoplanetary disks and exoplanet atmospheres have suggested a possible transfer of significant carbon isotope fractionation from disks to planets. For a clearer understanding of the…

We present new radio-frequency interferometric maps of emission from the 14NH3, 15NH3, and 14NH2D isotopologues of ammonia, and the 12CH3OH and 13CH3OH isotopologues of methanol toward Sgr B2(N). With a resolution of ~3'' (0.1 pc), we are…

星系天体物理 · 物理学 2018-12-26 E. A. C. Mills , J. Corby , A. R. Clements , N. Butterfield , P. Jones , M. Cunningham , J. Ott

The relative abundances of singly-deuterated methanol isotopologues, [CH$_{2}$DOH]/[CH$_{3}$OD], in star-forming regions deviate from the statistically expected ratio of 3. In Orion KL, the nearest high-mass star-forming region to Earth,…

星系天体物理 · 物理学 2022-10-12 Olivia H. Wilkins , Geoffrey A. Blake

We extend the survey for organics in the southern hemisphere by observing two cores in the Chamaeleon complex using NASA's Deep Space Network 70-m antenna in Canberra, Australia, over the frequency range of 18 to 25 GHz. We surveyed the…

Context: The depletion of heavy elements in cold cores of interstellar molecular clouds can lead to a situation where deuterated forms of H_3^+ are the most useful spectroscopic probes of the physical conditions. Aims: The aim is to predict…

星系天体物理 · 物理学 2015-05-14 O. Sipilä , E. Hugo , J. Harju , O. Asvany , M. Juvela , S. Schlemmer

High degrees of deuterium fractionation are commonly found in cold prestellar cores and in the envelopes around young protostars. As it brings strong constraints to chemical models, deuterium chemistry is often used to infer core history or…

星系天体物理 · 物理学 2016-02-17 A. Bacmann , F. Daniel , P. Caselli , C. Ceccarelli , D. Lis , C. Vastel , F. Dumouchel , F. Lique , E. Caux

We have conducted a spectral line survey in the 3 mm and 2 mm bands toward two positions in a spiral arm of M51 (NGC 5194) with the IRAM 30 m telescope. In this survey, we have identified 13 molecular species, including CN, CCH, N2H+, HNCO,…

星系天体物理 · 物理学 2015-06-19 Yoshimasa Watanabe , Nami Sakai , Kazuo Sorai , Satoshi Yamamoto

The inheritance of material across the star and planet formation process is traced by deuterium fractionation. We report here the first detection of doubly deuterated methanol towards pre-stellar cores. We study the deuterium fractionation…

星系天体物理 · 物理学 2023-01-11 Yuxin Lin , Silvia Spezzano , Paola Caselli

Methyl isocyanate (CH$_{3}$NCO) belongs to a select group of interstellar molecules considered to be relevant precursors in the formation of larger organic compounds, including those with peptide bonds. The molecule has only been detected…

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

Deuterated molecules and their molecular D/H-ratios (RD(D)) are important diagnostic tools to study the physical conditions of star-forming regions. The degree of deuteration, RD(D), can be significantly enhanced over the elemental…

Spectral line surveys reveal rich molecular reservoirs in G331.512-0.103, a compact radio source in the center of an energetic molecular outflow. In this first work, we analyse the physical conditions of the source by means of CH$_3$OH and…

We present the results of a single-pointing survey of 207 dense cores embedded in Planck Galactic Cold Clumps distributed in five different environments ($\lambda$ Orionis, Orion A, B, Galactic plane, and high latitudes) to identify dense…