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Related papers: Two dimensional ice mapping of molecular cores

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We present the first survey of dense gas towards Planck Galactic Cold Clumps (PGCCs). Observations in the J=1-0 transitions of HCO+ and HCN towards 621 molecular cores associated with PGCCs were performed using the Purple Mountain…

Astrophysics of Galaxies · Physics 2016-03-23 Jinghua Yuan , Yuefang Wu , Tie Liu , Tianwei Zhang , Jin Zeng Li , Hong-Li Liu , Fanyi Meng , Ping Chen , Runjie Hu , Ke Wang

We have measured the deuterium fractionation (through the column density ratio N(N2D+)/N(N2H+)) and the CO depletion factor (ratio between expected and observed CO abundance) in a sample of 10 high-mass protostellar candidates, in order to…

Astrophysics · Physics 2009-11-11 F. Fontani , P. Caselli , A. Crapsi , R. Cesaroni , S. Molinari , L. Testi , J. Brand

Thanks to the advent of sensitive and broad bandwidth instrumentation, complex organic molecules (COMs) have been found in a wide variety of interstellar environments, not only in our Galaxy but also in external galaxies up to a redshift of…

Astrophysics of Galaxies · Physics 2025-03-24 Izaskun Jimenez-Serra , Claudio Codella , Arnaud Belloche

We report the results of a wide field CO mapping in the region of IRAS 19312+1950. This IRAS object exhibits SiO/H$_2$O/OH maser emission, and is embedded in a chemically-rich molecular component, of which the origin is still unknown. In…

Solar and Stellar Astrophysics · Physics 2016-07-06 Jun-ichi Nakashima , Dmitry A. Ladeyschikov , Andrej M. Sobolev , Yong Zhang , Chih-Hao Hsia , Bosco H. K. Yung

Formic acid (HCOOH) and carbon dioxide (CO2) are simple species that have been detected in the interstellar medium. The solid-state formation pathways of these species under experimental conditions relevant to prestellar cores are primarily…

Solar and Stellar Astrophysics · Physics 2019-06-26 D. Qasim , T. Lamberts , J. He , K. -J. Chuang , G. Fedoseev , S. Ioppolo , A. C. A. Boogert , H. Linnartz

In this review, I discuss recent detailed studies of individual molecular clouds in M33 in higher rotational transitions of CO, 13CO, and the fine structure line of atomic carbon. These data reveal that the temperature and density of the…

Astrophysics · Physics 2007-05-23 C. D. Wilson

(Abridged) The observed presence of pure CO2 ice in protostellar envelopes is attributed to thermally induced ice segregation, but a lack of quantitative experimental data has prevented its use as a temperature probe. Quantitative…

Astrophysics of Galaxies · Physics 2015-05-13 Karin I. Öberg , Edith C. Fayolle , Herma M. Cuppen , Ewine F. van Dishoeck , Harold Linnartz

As part of the first high resolution far-IR spectral survey of the Orion KL region (Lerate et al. 2006), we observed 20 CO emission lines with Jup=16 to Jup=39 (upper levels from approx 752 K to 4294 K above the ground state). Observations…

The relation between ices in the envelopes and disks surrounding YSOs and those in the quiescent interstellar medium is investigated. For a sample of 31 stars behind isolated dense cores, ground-based and Spitzer spectra and photometry in…

Planet atmosphere and hydrosphere compositions are fundamentally set by accretion of volatiles, and therefore by the division of volatiles between gas and solids in planet-forming disks. For hyper-volatiles such as CO, this division is…

Earth and Planetary Astrophysics · Physics 2019-09-25 Alexia Simon , Karin I. Oberg , Mahesh Rajappan , Pavlo Maksiutenko

Icy grain mantles are commonly observed through infrared spectroscopy toward dense clouds, cloud cores, protostellar envelopes and protoplanetary disks. Up to 80% of the available oxygen, carbon and nitrogen are found in such ices; the most…

The central kiloparsec region of the Andromeda galaxy is relatively gas poor, while the interstellar medium appears to be concentrated in a ring-like structure at about 10 kpc radius. The central gas depletion has been attributed to a…

Astrophysics of Galaxies · Physics 2015-12-16 A. -L. Melchior , F. Combes

We present Spitzer IRS spectroscopy of CO2 ice bending mode spectra at 15.2 micrometer toward 19 young stellar objects with luminosity lower than 1 Lsun (3 with luminosity lower than 0.1 Lsun). Ice on dust grain surfaces can encode the…

Solar and Stellar Astrophysics · Physics 2015-06-11 Hyo Jeong Kim , Neal J. Evans , Michael M. Dunham , Jeong-Eun Lee , Klaus M. Pontoppidan

We have observed molecular cloud cores in the Orion A giant molecular cloud (GMC) in CCS, HC3N, DNC, and HN13C to study their chemical characteristics. We have detected CCS in the Orion A GMC for the first time. CCS was detected in about a…

Astrophysics of Galaxies · Physics 2015-05-20 Ken'ichi Tatematsu , Tomoya Hirota , Ryo Kandori , Tomofumi Umemoto

A partial submillimeter line-survey was performed toward 7 high-mass young stellar objects (YSOs) aimed at detecting H2CO, CH3OH, CH2CO, CH3CHO, C2H5OH, HCOOH, HNCO and NH2CHO. In addition, other organic species such as CH3CN have been…

Astrophysics · Physics 2009-11-13 S. E. Bisschop , J. K. Jorgensen , E. F. van Dishoeck , E. B. M. de Wachter

The chemical evolution in star forming regions is driven by the interplay between gas and ice mantles. Identifying the ice compositions at the early stage of star formation thus provides constraints on the chemical processes inaccessible…

Astrophysics of Galaxies · Physics 2026-02-06 Andrew M. Turner , Yao-Lun Yang , Rachel Gross , Nami Sakai , Ralf I. Kaiser

[Abridged] Observations of protoplanetary disks suggest that they are depleted in gas-phase CO. It has been posed that gas-phase CO is chemically consumed and converted into less volatile species through gas-grain processes. Observations of…

Instrumentation and Methods for Astrophysics · Physics 2022-10-05 J. Terwisscha van Scheltinga , N. F. W. Ligterink , A. D. Bosman , M. R. Hogerheijde , H. Linnartz

We have performed a multi-transition CO study of the centers of seven double-barred galaxies that exhibit a variety of molecular gas morphologies to determine if the molecular gas properties are correlated with the nuclear morphology and…

Astrophysics · Physics 2009-11-07 Glen Petitpas , Christine Wilson

(Abridged) We aim to enlarge the number of known hot corinos and carry out a first comparative study with hot cores. The ultimate goal is to understand whether complex organic molecules form in the gas phase or on grain surfaces, and what…

Complex organic molecules (COMs) detected in the gas phase are thought to be mostly formed on icy grains, but no unambiguous detection of icy COMs larger than CH3OH has been reported so far. Exploring this matter in more detail has become…

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