2006/11/29 by Masako Yamada, M. Yamada, H. Koyama +5 · 1 citation
Earth and Planetary Sciences · Physics and Astronomy · #Astrophysics and Star Formation Studies #Atmospheric Ozone and Climate #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/511257
published as Astrophys.J.657:849-859,2007 · 16 pages, 10 figures : accepted for publication in ApJ. PDF version with high resolution figures is available (http://yso.mtk.nao.ac.jp/~ymasako/paper/ms_hires.pdf)
arxiv created 2006/11/29 · openalex publication_date 2007/03/06 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We examine observational characteristics of multiphase turbulent flows in the diffuse interstellar medium (ISM) using a synthetic radiation field of atomic and molecular lines. We consider the multiphase ISM, which is formed by thermal instability under the irradiation of UV photons with moderate visual extinction A V ~ 1. Radiation field maps of C + , C 0 , and CO line emissions were generated by calculating the non-local thermodynamic equilibrium (non-LTE) level populations from the results of high-resolution hydrodynamic simulations of diffuse ISM models. By analyzing the synthetic radiation field of carbon lines of [C II] 158 μm, [C I] 3 P 2 - 3 P 1 (809 GHz), 3 P 1 - 3 P 0 (492 GHz), and CO rotational transitions, we found a high ratio between the lines of high- and low-excitation energies in the diffuse multiphase ISM. This shows that simultaneous observations of the lines of warm- and cold-gas tracers will be useful in examining the thermal structure, and hence the origin, of diffuse interstellar clouds.