A computer program for fast non-LTE analysis of interstellar line spectra
F. F. S. van der Tak,F. F. S. van der Tak,John H. Black,Fredrik L. Schöier,D. J. Jansen,E. F. van Dishoeck +5 more
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TLDR
In this paper, the authors present a computer program to calculate the intensities of atomic and molecular lines produced in a uniform medium, based on statistical equilibrium calculations involving collisional and radiative processes and including radiation from background sources.Abstract:
The large quantity and high quality of modern radio and infrared line observations require efficient modeling techniques to infer physical and chemical parameters such as temperature, density, and molecular abundances. We present a computer program to calculate the intensities of atomic and molecular lines produced in a uniform medium, based on statistical equilibrium calculations involving collisional and radiative processes and including radiation from background sources. Optical depth effects are treated with an escape probability method. The program is available on the World Wide Web at http://www.sron.rug.nl/~vdtak/radex/index.shtml . The program makes use of molecular data files maintained in the Leiden Atomic and Molecular Database (LAMDA), which will continue to be improved and expanded. The performance of the program is compared with more approximate and with more sophisticated methods. An Appendix provides diagnostic plots to estimate physical parameters from line intensity ratios of commonly observed molecules. This program should form an important tool in analyzing observations from current and future radio and infrared telescopes. Note: Accepted by AA 18 A4 pages, 11 figures;read more
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First-generation science cases for ground-based terahertz telescopes
Hiroyuki Hirashita,Patrick M. Koch,Satoki Matsushita,Shigehisa Takakuwa,Masanori Nakamura,Keiichi Asada,Hauyu Baobab Liu,Yuji Urata,Yuji Urata,Ming-Jye Wang,Wei-Hao Wang,Satoko Takahashi,Ya-Wen Tang,Hsian Hong Chang,Kuiyun Huang,Oscar Morata,Masaaki Otsuka,Kai-Yang Lin,An-Li Tsai,Yen-Ting Lin,Sundar Srinivasan,Pierre Martin-Cocher,Hung Yi Pu,Francisca Kemper,Nimesh A. Patel,Paul K. Grimes,Yau De Huang,Chih Chiang Han,Yen Ru Huang,Hiroaki Nishioka,Lupin Chun Che Lin,Qizhou Zhang,Eric Keto,Roberto Burgos,Ming-Tang Chen,Makoto Inoue,Paul T. P. Ho +36 more
TL;DR: In this article, the authors discuss science cases for a first-generation 10-m class terahertz (THz) telescope, focusing on the Greenland Telescope as an example of such a facility.
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References
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