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Related papers: The Horsehead nebula, a template source for inters…

200 papers

Certain planetary nebulae contain shells, filaments, or globules of cold gas and dust whose heating and chemistry are likely driven by UV and X-ray emission from their central stars and from wind-collision-generated shocks. We present the…

Solar and Stellar Astrophysics · Physics 2019-05-22 Jesse Bublitz , Joel H. Kastner , Miguel Santander-García , Valentin Bujarrabal , Javier Alcolea , Rodolfo Montez

Very recently, molecular rotational transitions observed in the photon-dominated region of the Horsehead nebula have been attributed to l-C3H+. In an effort to corroborate this finding, we employed state-of-the art and proven high-accuracy…

High Energy Astrophysical Phenomena · Physics 2013-05-09 Xinchuan Huang , Ryan C. Fortenberry , Timothy J. Lee

As many organic molecules, formic acid (HCOOH) has two conformers (trans and cis). The energy barrier to internal conversion from trans to cis is much higher than the thermal energy available in molecular clouds. Thus, only the most stable…

Astrophysics of Galaxies · Physics 2016-11-23 S. Cuadrado , J. R. Goicoechea , O. Roncero , A. Aguado , B. Tercero , J. Cernicharo

We show radio continuum images of several molecular complexes in the inner Galaxy and report the presence of dark features that coincide with dense molecular clouds. Unlike infrared dark clouds, these features which we call "radio dark…

Astrophysics of Galaxies · Physics 2015-06-11 F. Yusef-Zadeh

The solar system is moving through the partially ionized local interstellar cloud (LIC). The ionized matter of the LIC interacts with the expanding solar wind forming the heliospheric interface. The neutral component (interstellar atoms)…

Astrophysics · Physics 2015-06-24 V. V. Izmodenov , J. Geiss , R. Lallement , G. Gloeckler , V. B. Baranov , Y. G. Malama

Molecules that trace the high-density regions of the interstellar medium have been observed in (ultra-)luminous (far-)infrared galaxies, in order to initiate multiple-molecule multiple-transition studies to evaluate the physical and…

Astrophysics · Physics 2009-11-13 W. A. Baan , C. Henkel , A. F. Loenen , A. Baudry , T. Wiklind

High-density molecular gas plays a vital role in supporting star formation within galaxies. However, traditional tracers of dense gas, such as the low-$J$ transitions of HCN and HCO$^+$, are predominantly optically thick. This…

Astrophysics of Galaxies · Physics 2025-09-16 Fei Li , Zhi-Yu Zhang , Junzhi Wang , Gan Luo

Studying the atomic-to-molecular transition is essential for understanding the evolution of interstellar medium. The linear edge of Taurus molecular cloud, clearly identified in the $^{13}$CO(1-0) intensity map, serves as an ideal site for…

Astrophysics of Galaxies · Physics 2025-04-03 Ningyu Tang , Feihang Miao , Gan Luo , Di Li , Junzhi Wang , Fujun Du , Donghong Wu , Shu Liu

This paper presents maps of the J=2-1 transition of CO toward the Draco Nebula Intermediate Velocity Cloud (IVC). The maps cover 8500 square arcmin with a velocity resolution of 0.33 km~s$^{-1}$ and angular resolution of 38", or 0.11 pc at…

Astrophysics of Galaxies · Physics 2024-06-04 John H. Bieging , Shuo Kong

In the interstellar cold gas, the chemistry of formaldehyde (H$_2$CO) can be essential to explain the formation of complex organic molecules. On this matter, the massive and energetic protostellar object G331 is still unexplored and, hence,…

Astrophysics of Galaxies · Physics 2023-08-09 Edgar Mendoza , Miguel Carvajal , Manuel Merello , Leonardo Bronfman , Heloisa M. Boechat-Roberty

The Rosette Nebula is a well-known H II region shaped by the interaction of gas with the OB stars of the NGC 2244 stellar association. Located within the remnant of a giant molecular cloud, it exhibits a complex structure of ionized gas,…

We present synthetic line observations of a simulated molecular cloud, utilising a self-consistent treatment of the dynamics and time-dependent chemical evolution. We investigate line emission from the three most common CO isotopologues…

Astrophysics of Galaxies · Physics 2024-06-12 F. D. Priestley , P. C. Clark , S. C. O. Glover , S. E. Ragan , O. Fehér , L. R. Prole , R. S. Klessen

Molecular emission was imaged with ALMA from numerous components near and within bright H2-emitting knots and absorbing dust globules in the Crab Nebula. These observations provide a critical test of how energetic photons and particles…

Our understanding of how molecular clouds form in the interstellar medium (ISM) would be greatly helped if we had a reliable observational tracer of the gas flows responsible for forming the clouds. Fine structure emission from singly…

Astrophysics of Galaxies · Physics 2019-05-14 Paul C. Clark , Simon C. O. Glover , Sarah E. Ragan , Ana Duarte-Cabral

We present the first detection of gas phase S2H in the Horsehead, a moderately UV-irradiated nebula. This confirms the presence of doubly sulfuretted species in the interstellar medium and opens a new challenge for sulfur chemistry. The…

We present recent observations of small hydrocarbons (C3H2, C2H, C4H) with high abundances in the Photo-Dissociation Region of the Horsehead nebula. Our results show for the first time observational indications that the small hydrocarbon…

Astrophysics · Physics 2007-05-23 David Teyssier , David Fosse , Maryvonne Gerin , Jerome Pety , Alain Abergel , Emilie Habart

Since the launch of the Herschel Space Observatory, our understanding about the photo-dissociation regions (PDR) has taken a step forward. In the bandwidth of the Fourier Transform Spectrometer (FTS) of the Spectral and Photometric Imaging…

We aim to better understand the emission of molecular tracers of the diffuse and dense gas in giant molecular clouds and the influence that metallicity, optical extinction, density, far-UV field, and star formation rate have on these…

We present CO velocity fields and rotation curves for a sample of nearby galaxies, based on data from the HERACLES survey. We combine our data with literature THINGS, SINGS and KINGFISH results to provide a comprehensive sample of mass…

Astrophysics of Galaxies · Physics 2016-04-06 Bradley S. Frank , W. J. G. de Blok , F. Walter , A. Leroy , C Carignan