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Related papers: Two dimensional ice mapping of molecular cores

200 papers

We report the first fully sampled maps of the distribution of interstellar CO2 ices, H2O ices and total hydrogen nuclei, as inferred from the 9.7 micron silicate feature, toward the star-forming region Cepheus A East with the IRS instrument…

This paper presents Spitzer-IRS spectroscopy of the CO2 15.2 micron bending mode toward a sample of 50 embedded low-mass stars in nearby star-forming clouds, taken mostly from the ``Cores to Disks (c2d)'' Legacy program. The average…

The study of molecular gas is crucial for understanding star formation, feedback, and the broader ecosystem of a galaxy as a whole. However, we have limited understanding of its physics and distribution in all but the nearest galaxies. We…

Astrophysics of Galaxies · Physics 2017-05-18 Patrick C. Breysse , Mubdi Rahman

We present an overview of a high-mass star formation region through the major (sub-)mm, and far-infrared cooling lines to gain insight into the physical conditions and the energy budget of the molecular cloud. We used the KOSMA 3m telescope…

Astrophysics · Physics 2009-11-11 H. Jakob , C. Kramer , R. Simon , N. Schneider , V. Ossenkopf , S. Bontemps , U. U. Graf , J. Stutzki

We investigate molecular evolution from a molecular cloud core to a first hydrostatic core in three spatial dimensions. We perform a radiation hydrodynamic simulation in order to trace fluid parcels, in which molecular evolution is…

Solar and Stellar Astrophysics · Physics 2015-06-05 Kenji Furuya , Yuri Aikawa , Kengo Tomida , Tomoaki Matsumoto , Kazuya Saigo , Kohji Tomisaka , Franck Hersant , Valentine Wakelam

We have investigated the two-dimensional (R,Z) distribution of deuterated molecular species in circumstellar disks around young stellar objects. The abundance ratios between singly deuterated and normal molecules (``D/H ratios'') in disks…

Astrophysics · Physics 2009-11-07 Y. Aikawa , E. Herbst

We present first results of neutral carbon ([CI], 3P1 - 3P0 at 492 GHz) and carbon monoxide (13CO, J = 1 - 0) mapping in the Vela Molecular Ridge cloud C (VMR-C) and G333 giant molecular cloud complexes with the NANTEN2 and Mopra…

Astrophysics of Galaxies · Physics 2015-06-23 N. Lo , M. R. Cunningham , P. A. Jones , L. Bronfman , P. C. Cortes , R. Simon , V. Lowe , L. Fissel , G. Novak

We have mapped six molecular cloud cores in the Orion A giant molecular cloud (GMC), whose kinetic temperatures range from 10 to 30 K, in CCS and N2H+ with Nobeyama 45 m radio telescope to study their chemical characteristics. We identified…

Up to 90% of the chemical reactions during star formation occurs on ice surfaces, probably including the formation of complex organics. Only the most abundant ice species are however observed directly by infrared spectroscopy. This study…

Solar and Stellar Astrophysics · Physics 2015-05-13 Karin I. Oberg , Sandrine Bottinelli , Ewine F. van Dishoeck

We present near infrared spectroscopic observations of 19 molecular clouds made using the AKARI satellite, and the data reduction pipeline written to analyse those observations. The 2.5 --~5 $\mu$m spectra of 30 objects -- 22 field stars…

Solar and Stellar Astrophysics · Physics 2015-06-16 J. A. Noble , H. J. Fraser , Y. Aikawa , K. M. Pontoppidan , I. Sakon

Our understanding of the physical and chemical structure of pre-stellar cores, the simplest star-forming sites, has significantly improved since the last IAU Symposium on Astrochemistry (South Korea, 1999). Research done over these years…

Astrophysics · Physics 2015-06-24 M. Tafalla

Massive star-forming regions exhibit an extremely rich and diverse chemistry, which in principle provides a wealth of molecular probes, as well as laboratories for interstellar prebiotic chemistry. Since the chemical structure of these…

Observations of dark cloud cores have been carried out in the mid-infrared using ISOCAM and in the far-infrared using ISOPHOT, both aboard the Infrared Space Observatory. The cores are in most cases detected in emission at 200 and 170…

Astrophysics · Physics 2007-05-23 Aurore Bacmann , Philippe Andre , Derek Ward-Thompson

Context. The formation and destruction of molecules in the interstellar medium is a complex interplay between gas-phase reactions as well as processes on grain surfaces and within icy mantles. For many decades, the gas-phase composition of…

CO2 ice is one of the most abundant components in ice-coated interstellar ices besides H2O and CO, but the most favorable path to CO2 ice is still unclear. Molecular dynamics calculations on the ultraviolet photodissociation of different…

Chemical Physics · Physics 2015-06-17 Carina Arasa , Marc C. van Hemert , Ewine F. van Dishoeck , Geert-Jan Kroes

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

The detection of complex organic molecules (COMs) toward cold sources such as pre-stellar cores (with T<10 K), has challenged our understanding of the formation processes of COMs in the interstellar medium. Recent modelling on COM chemistry…

Five regions of massive star formation have been observed in various molecular lines in the frequency range $\sim 85-89$ GHz. The studied regions possess dense cores, which host young stellar objects. The physical parameters of the cores…

Astrophysics of Galaxies · Physics 2016-10-19 L. E. Pirogov , V. M. Shul'ga , I. I. Zinchenko , P. M. Zemlyanukha , O. N. Patoka , M. Thomasson

Freeze-out of the gas phase elements onto cold grains in dense interstellar and circumstellar media builds up ice mantles consisting of molecules that are mostly formed in situ (H2O, NH3, CO2, CO, CH3OH, and more). This review summarizes…

Astrophysics of Galaxies · Physics 2015-09-23 Adwin Boogert , Perry Gerakines , Douglas Whittet

We present models for the chemistry in gas moving towards the ionization front of an HII region. When it is far from the ionization front, the gas is highly depleted of elements more massive than helium. However, as it approaches the…

Astrophysics · Physics 2009-11-13 S. Viti , T. W. Hartquist , P. C. Myers