J/A+AS/142/113 C3H2 and SiC2 collisional rates (Chandra+, 2000)
Collisional rates for asymmetrical top molecules
Chandra S., Kegel W.H.
<Astron. Astrophys. Suppl. Ser. 142, 113 (2000)>
=2000A&AS..142..113C 2000A&AS..142..113C (SIMBAD/NED BibCode)
ADC_Keywords: Atomic physics
Keywords: ISM: molecules - molecular data
Abstract:
Collisional rate coefficients for rotational transitions in C3H2 and
SiC2 due to collisions with H2 molecules are calculated. The C3H2 has
two distinct species, ortho and para, whereas the SiC2 has only ortho
specie due to spin statistics for the identical carbon nuclei. For
ortho- and para-C3H2 we accounted for 47 and 48 energy levels,
respectively. The calculations are done for the kinetic temperatures
30, 60, 90, and 120 K. For ortho-SiC2, we accounted for 40 energy
levels and the calculations are done for the kinetic temperatures 25,
50, 75, 100, and 125 K. The results are reported here for the
transitions in the upward direction. The values for the downward
direction can easily be calculated with the help of the detailed
equilibrium equation.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tables.dat 62 12736 Collisional rate coefficients (tables 3 to 5)
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Byte-by-byte Description of file: tables.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- El Element
12- 14 I3 K T Temperature
16- 37 A22 --- Trans Transition between two levels
42- 50 D9.3 cm+3/s Rate Collisional rate coefficient for the
transition from the lower level (l) to the
upper level (u) at the temperature T
56- 57 I2 --- l Lower level
61- 62 I2 --- u Upper level
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Acknowledgements: W.H. Kegel
(End) Patricia Bauer [CDS] 16-Dec-1999