English
Related papers

Related papers: A simple approach to CO cooling in molecular cloud…

200 papers

Using archival, high-resolution far-ultraviolet HST/STIS spectra of 34 Galactic O and B stars, we measure CI column densities and compare them with measurements from the literature of CO and H_2 with regard to understanding the presence of…

Astrophysics of Galaxies · Physics 2014-11-20 Eric B. Burgh , Kevin France , Edward B. Jenkins

Molecular emission arising from the interactions of supernova remnant (SNR) shock waves and molecular clouds provide a tool for studying the dispersion and compression that might kick-start star formation as well as understanding cosmic ray…

Astrophysics of Galaxies · Physics 2024-03-04 Nguyen Fuda , Le-Ngoc Tram , William T. Reach

Cooling is the main process leading to the condensation of gas in the dark matter potential wells and consequently to star and structure formation. In a metal-free environment, the main available coolants are H, He, H$_2$ and HD; once the…

Astrophysics · Physics 2009-11-13 U. Maio , K. Dolag , B. Ciardi , L. Tornatore

The winds and radiation from massive stars clear out large cavities in the interstellar medium. These bubbles, as they have been called, impact their surrounding molecular clouds and may influence the formation of stars therein. Here we…

Astrophysics of Galaxies · Physics 2014-11-20 Christopher N. Beaumont , Jonathan P. Williams

Low-energy cosmic rays are a fundamental source of ionization for molecular clouds, influencing their chemical, thermal and dynamical evolution. The purpose of this work is to explore the possibility that a low-energy component of…

Solar and Stellar Astrophysics · Physics 2015-05-13 Marco Padovani , Daniele Galli , Alfred E. Glassgold

In this paper we present computations of the integrated metal-ion column densities produced in the post-shock cooling layers behind fast, radiative shock-waves. For this purpose, we have constructed a new shock code that calculates the…

Astrophysics · Physics 2011-02-11 Orly Gnat , Amiel Sternberg

This work follows Lykins et al. discussion of classic plasma cooling function at low density and solar metallicity. Here we focus on how the cooling function changes over a wide range of density (n_H<10^12 cm^(-3)) and metallicity (Z<30Z…

Instrumentation and Methods for Astrophysics · Physics 2014-05-12 Ye Wang , G. J. Ferland , M. L. Lykins , R. L. Porter , P. A. M. van Hoof , R. J. R. Williams

The formation of molecular gas in interstellar clouds is a slow process, but is enhanced by gas compression. Magnetohydrodynamic (MHD) waves create compressed quasiperiodic linear structures, referred to as striations. Striations are…

Astrophysics of Galaxies · Physics 2023-05-10 R. Skalidis , K. Gkimisi , K. Tassis , G. V. Panopoulou , V. Pelgrims , A. Tritsis , P. F. Goldsmith

We explore molecular cloud properties and the physics of CO transition lines in z >~ 6 Lyman-break galaxies and predict their CO fluxes using an analytic formalism built from global models of star formation in high-redshift galaxies that…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-09 Joseph A. Muñoz , Steven R. Furlanetto

Diffusion of species in icy dust grain mantles is a fundamental process that shapes the chemistry of interstellar regions; yet measurements of diffusion in interstellar ice analogs are scarce. Here we present measurements of CO diffusion…

Astrophysics of Galaxies · Physics 2018-01-24 Ilsa R. Cooke , Karin I. Öberg , Edith C. Fayolle , Zoe Peeler , Jennifer B. Bergner

We present far-IR (57-196 mu) spectra of 21 protostars in the Orion molecular clouds, obtained with the Photodetector Array Camera and Spectrometer (PACS) onboard the Herschel Space observatory, as part of the Herschel Orion Protostar…

Seven isolated, nearby low-mass starless molecular cloud cores have been observed as part of the Herschel key program Earliest Phases of Star formation (EPoS). By applying a ray-tracing technique to the obtained continuum emission and…

Aims: Ices in dense star-forming cores contain the bulk of volatile molecules apart from H2 and thus represent a large fraction of dark cloud chemistry budget.To directly constrain the freeze-out profile of CO, the formation route of CO2…

Astrophysics · Physics 2009-11-11 K. M. Pontoppidan

Experimental measurements and theoretical calculations of state-to-state rate coefficients for rotational energy transfer of CO in collision with H$_2$ are reported at the very low temperatures prevailing in dense interstellar clouds (5 -…

We analyze the conditions for detection of CO(1-0) emission in the Large Magellanic Cloud (LMC), using the recently completed second NANTEN CO survey. In particular, we investigate correlations between CO integrated intensity and HI…

Astrophysics of Galaxies · Physics 2011-02-11 T. Wong , A. Hughes , Y. Fukui , A. Kawamura , N. Mizuno , J. Ott , E. Muller , J. L. Pineda , D. E. Welty , S. Kim , Y. Mizuno , M. Murai , T. Onishi

Astrochemical models can be greatly simplified, with obvious computational advantages, if the reaction networks for key species can be reduced to a bare minimum. In addition, if chemical equilibrium holds, then simple analytical solutions…

Astrophysics of Galaxies · Physics 2025-08-26 Jonathan Rawlings , Eric Keto , Paola Caselli

We present an analysis of the outer Galaxy giant molecular filament (GMF) G214.5-1.8 (G214.5) using IRAM 30m data of $^{12}$CO, $^{13}$CO and C$^{18}$O. We find that the $^{12}$CO (1-0) and (2-1) derived excitation temperatures are near…

Astrophysics of Galaxies · Physics 2024-01-11 S. D. Clarke , V. A. Makeev , Á. Sánchez-Monge , G. M. Williams , Y. -W. Tang , S. Walch , R. Higgins , P. C. Nürnberger , S. Suri

Investigating the reliability of the assumption of instantaneous chemical equilibrium (ICE) for calculating the CO number density in the solar atmosphere is of crucial importance for the resolution of the long-standing controversy over the…

Astrophysics · Physics 2009-11-07 A. Asensio Ramos , J. Trujillo Bueno , M. Carlsson , J. Cernicharo

The gas at the surfaces of molecular clouds in galaxies is heated and dissociated by photons from young stars both near and far. HI resulting from the dissociation of molecular hydrogen H2 emits hyperfine line emission at 21 cm, and warmed…

Astrophysics · Physics 2009-11-10 Ronald J. Allen , Harold I. Heaton , Michael J. Kaufman

Understanding the molecular gas content in the interstellar medium (ISM) is crucial for studying star formation and galaxy evolution. The CO-to-H$_2$ ($X_{\rm CO}$) and the [CI]-to-H$_2$ ($X_{\rm CI}$) conversion factors are widely used to…

‹ Prev 1 4 5 6 7 8 10 Next ›