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
Citations
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The Circumstellar Structure and Excitation Effects around the Massive Protostar Cepheus A HW 2
José M. Torrelles,Nimesh A. Patel,Salvador Curiel,Paul T. P. Ho,Paul T. P. Ho,Guido Garay,Luis F. Rodríguez +6 more
TL;DR: In this paper, the authors show that the flattened disk structure of the dust emission observed by Patel et al. is preserved at the 0.3'' scale, showing an elongated structure of ~0.6'' size (450 AU) peaking on HW 2.
Journal ArticleDOI
The molecular gas content of the Pipe Nebula - I. Direct evidence of outflow-generated turbulence in B59?
Ana Duarte-Cabral,Ana Duarte-Cabral,Antonio Chrysostomou,Nicolas Peretto,Gary A. Fuller,Brenda C. Matthews,Brenda C. Matthews,G. Schieven,G. Schieven,G. R. Davis +9 more
TL;DR: In this article, the authors used HARP at the James Clerk Maxwell Telescope to study the B59 region in the J = 3 → 2 transition of 12CO to study kinematics and energetics of the outflows, and the same transitions of 13CO and C18O.
Journal ArticleDOI
ALMA Observations of Multiple CO and C Lines toward the Active Galactic Nucleus of NGC 7469: An X-Ray-dominated Region Caught in the Act
Takuma Izumi,Dieu D. Nguyen,Masatoshi Imanishi,Taiki Kawamuro,Shunsuke Baba,Suzuka Nakano,Kotaro Kohno,Satoki Matsushita,David S. Meier,Jean L. Turner,Tomonari Michiyama,Nanase Harada,Sergio Martín,Kouichiro Nakanishi,Shuro Takano,Tommy Wiklind,Naomasa Nakai,Pei-Ying Hsieh +17 more
TL;DR: Izumi et al. as discussed by the authors used the Atacama Large Millimeter/submillimeter Array (ALMA) to map CO emission lines around the type 1 active galactic nucleus (AGN) of NGC 7469.
Journal ArticleDOI
Active Galactic Nucleus and Extended Starbursts in a Midstage Merger VV 114
Daisuke Iono,Toshiki Saito,Min S. Yun,Ryohei Kawabe,Daniel Espada,Yoshiaki Hagiwara,Masatoshi Imanishi,Takuma Izumi,Kotaro Kohno,Kentaro Motohara,Kouichiro Nakanishi,Hajime Sugai,Ken Tateuchi,Yoichi Tamura,Junko Ueda,Junko Ueda,Yuzuru Yoshii +16 more
TL;DR: In this paper, the Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 0 observations of HCO + (4-3) and HCN (4−3) toward a mid-stage infrared bright merger, VV 114, have revealed a compact nuclear (< 200 pc) and extended (3-4 kpc) dense gas distribution across the eastern part of the galaxy pair.
Journal ArticleDOI
Warm gas towards young stellar objects in Corona Australis - Herschel/PACS observations from the DIGIT key programme
Johan E. Lindberg,Jes K. Jørgensen,Joel D. Green,Gregory J. Herczeg,Gregory J. Herczeg,Odysseas Dionatos,Odysseas Dionatos,Neal J. Evans,Agata Karska,S. F. Wampfler +9 more
TL;DR: In this paper, the effects of external irradiation on the chemistry and physics in the protostellar envelope around low-mass young stellar objects are poorly understood, and a deconvolution algorithm is developed to separate the point-source emission from the extended emission.
References
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