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Related papers: The TW Hya Rosetta Stone Project II: Spatially res…

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We report new computational and experimental evidence of an efficient and astrochemically relevant formation route to formaldehyde (H$_2$CO). This simplest carbonylic compound is central to the formation of complex organics in cold…

We present Green Bank Telescope (GBT) observations of the 3(12)-3(13) (29 GHz) and 4(13)-4(14) (48 GHz) transitions of the H2CO molecule toward a sample of 23 well-studied star-forming regions. Analysis of the relative intensities of these…

Astrophysics of Galaxies · Physics 2015-05-30 Patrick I. McCauley , Jeffrey G. Mangum , Alwyn Wootten

The first generation of protogalaxies likely formed out of primordial gas via H2-cooling in cosmological minihalos with virial temperatures of a few 1000K. However, their abundance is likely to have been severely limited by feedback…

Astrophysics · Physics 2009-11-07 S. Peng Oh , Zoltan Haiman

Abundance ratios of the nuclear-spin isomers of H$_2$O and NH$_3$ have been measured in about two dozen comets, with a mean value corresponding to a nuclear-spin temperature of $\sim$ 30 K. The real meaning of these unequilibrated…

Interstellar formamide (NH2CHO) has recently attracted significant attention due to its potential role as a molecular building block in the formation of precursor biomolecules relevant for the origin of life. Its formation, whether on the…

Earth and Planetary Astrophysics · Physics 2018-10-09 Albert Rimola , Dimitrios Skouteris , Nadia Balucani , Cecilia Ceccarelli , Joan Enrique-Romero , Vianney Taquet , Piero Ugliengo

HH 212 is a nearby (400 pc) Class 0 protostellar system recently found to host a "hamburger"-shaped dusty disk with a radius of ~ 60 AU, deeply embedded in an infalling-rotating flattened envelope. We have spatially resolved this…

Astrophysics of Galaxies · Physics 2017-07-05 Chin-Fei Lee , Zhi-Yun Li , Paul T. P. Ho , Naomi Hirano , Qizhou Zhang , Hsien Shang

A very low ortho-to-para ratio (OPR) of 0.1-0.5 was previously reported in the Orion Bar photon-dominated region (PDR), based on observations of two optically thin $\mathrm{H_2^{18}O}$ lines which were analyzed by using a single-slab large…

Astrophysics of Galaxies · Physics 2019-11-27 T. Putaud , X. Michaut , F. Le Petit , E. Roueff , D. C. Lis

Spitzer-IRS maps of H_2 pure rotational lines from S(0) to S(7) in 3 outflows from Class 0 sources - L1448, BHR71, and NGC2071 - are presented. These lines are used, in conjunction with available rovibrational, near-IR H_2 lines, to probe…

Solar and Stellar Astrophysics · Physics 2015-05-28 T. Giannini , B. Nisini , D. Neufeld , Y. Yuan , S. Antoniucci , A. Gusdorf

The role of HD cooling in the formation of primordial objects is examined by means of a great number of 1-D models of the collapse of halos, exploring a wide range of masses and virialization redshifts. We find that HD has very little…

Astrophysics · Physics 2008-11-26 E. Ripamonti

Cold cores in interstellar molecular clouds represent the very first phase in star formation. The physical conditions of these objects are studied in order to understand how molecular clouds evolve and how stellar masses are determined. The…

Astrophysics · Physics 2009-11-13 J. Harju , M. Juvela , S. Schlemmer , L. K. Haikala , K. Lehtinen , K. Mattila

Formaldehyde (H$_2$CO) and methanol (CH$_3$OH) have served as traditional tracers of the star formation process for decades. Studies of the environments which produce these species, though, have pointed to significant differences in the…

Astrophysics of Galaxies · Physics 2025-05-23 K. -Y. Huang , E. Behrens , M. Bouvier , S. Viti , J. G. Mangum , C. Eibensteiner

The simultaneous detection of organic molecules of the form C$_2$H$_{\text{n}}$O, such as ketene (CH$_2$CO), acetaldehyde (CH$_3$CHO), and ethanol (CH$_3$CH$_2$OH), toward early star-forming regions offers hints of shared chemical history.…

Astrophysics of Galaxies · Physics 2021-06-16 K. -J. Chuang , G. Fedoseev , C. Scirè , G. A. Baratta , C. Jäger , Th. Henning , H. Linnartz , M. E. Palumbo

We have studied the evolution of molecular gas during the early stages of protostellar collapse. In addition to allowing for the freeze out of `heavy' species on to grains, we have computed the variation of population densities of the…

Astrophysics · Physics 2009-11-11 D. R. Flower , G. Pineau des Forets , C. M. Walmsley

We present ISO observations of the S(0), S(1), S(2), and S(3) rotational lines of molecular hydrogen from two molecular clouds near the Galactic Center (GC). We have also measured continuum dust emission at infrared wavelengths with ISO and…

We report high signal-to-noise Spitzer IRS spectra of a sample of eleven classical T Tauri stars. Molecular emission from rotational transitions of H2O and OH and ro-vibrational bands of simple organic molecules (CO2, HCN, C2H2) is common…

Astrophysics of Galaxies · Physics 2015-05-27 John S. Carr , Joan R. Najita

Aims. Formamide (HCONH2) is the simplest molecule containing the peptide bond first detected in the gas phase in Orion-KL and SgrB2. In recent years, it has been observed in high temperature regions such as hot corinos, where thermal…

Instrumentation and Methods for Astrophysics · Physics 2020-04-22 Maria Angela Corazzi , Davide Fedele , Giovanni Poggiali , John Robert Brucato

Emission from the pure rotational transitions of H$_2$ traces warm molecular gas, providing insight into its temperature distribution and local heating conditions. We have extended previous power-law H$_2$ temperature models to account for…

1-propanol (CH3CH2CH2OH) is a three carbon-bearing representative of primary linear alcohols that may have its origin in the cold dark cores in interstellar space. To test this, we investigated in the laboratory whether 1-propanol ice can…

Solar and Stellar Astrophysics · Physics 2019-06-26 D. Qasim , G. Fedoseev , K. -J. Chuang , V. Taquet , T. Lamberts , J. He , S. Ioppolo , E. F. van Dishoeck , H. Linnartz

The radical hydrocarbon molecule C$_2$H is widely detected in various stages of star and planet formation, and has emerged as a useful tracer of high-C/O gas within the photochemically active surface layers of mature (Class II)…

Astrophysics of Galaxies · Physics 2025-08-07 Jack G. Anderson , Jennifer B. Bergner , Yao-Lun Yang , Yichen Zhang , Nami Sakai

Observing and characterizing pre- and protostellar cores in the earliest and densest stages of star formation is challenging due to their short timescales and high densities, limiting the suitable tracers and targets. We conducted…

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