J/ApJ/827/62 Rate coefficients for H2(v,j)+H2(v',j') (Mandy, 2016)
State-specific dissociation rates for H2(v,j)+H2(v',j').
Mandy M.E.
<Astrophys. J., 827, 62-62 (2016)>
=2016ApJ...827...62M 2016ApJ...827...62M (SIMBAD/NED BibCode)
ADC_Keywords: Atomic physics
Keywords: ISM: molecules; molecular data; molecular processes
Abstract:
State-specific rate coefficients for the dissociation of H2 as the
result of collisions with H2 were calculated for all combinations of
(v,j) with an internal energy below 1eV. Full-dimensional
quasiclassical trajectories were calculated using the BMKP2
interaction potential with a minimum of 80000 trajectories at each
translational energy. Additional large batches of trajectories were
carried out to calculate the cross sections near the threshold to
dissociation to attain the desired precision of the rate coefficients.
A piecewise linear excitation function was used to calculate the rate
coefficient between 100 and 100000K. The resulting state-specific rate
coefficients, γ, were parametrized as a function of temperature
over the range 600-10000K using: log10γ(t)=a+bz+cz2-d(1/t-1)
where t=T/4500K and z=log10t. The values of the resulting rate
coefficients were sensitive to the internal energy of both molecules,
with initial vibrational energy having a slightly greater effect than
rotational energy. This effect diminished as temperature increased.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 11 16 Energy levels of selected (v,j) states
table2.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 3000K
table3.dat 38 256 Fitting parameters for rate coefficients
table4.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 450K
table5.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 600K
table6.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 780K
table7.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 1000K
table8.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 1400K
table9.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 2000K
table10.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 4500K
table11.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 6000K
table12.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 7800K
table13.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 10000K
table14.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 14000K
table15.dat 29 256 Rate coefficients and standard errors (cm3/s)
at 20000K
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 I1 --- v Vibrational quantum number v
3 I1 --- j Rotational quantum number j
5- 11 F7.5 eV E [0.26/1] Energy level (1)
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Note (1): Energy relative to potential energy minimum of H2. For comparison,
the energy at the dissociation limit is 4.74825eV.
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Byte-by-byte Description of file: table2.dat table[4-9].dat table1[0-5].dat
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Bytes Format Units Label Explanations
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1 A1 --- --- [(]
2 I1 --- v [0/1]? v initial state of first hydrogen molecule
3 A1 --- --- [,]
4 I1 --- j [0/9]? j initial state of first hydrogen molecule
5 A1 --- --- [)]
7 A1 --- --- [(]
8 I1 --- vp [0/1]? vp initial state of second hydrogen molecule
9 A1 --- --- [,]
10 I1 --- jp [0/9]? jp initial state of second hydrogen molecule
11 A1 --- --- [)]
13- 20 E8.2 cm3/s coeff [6.19e-75/1.18e-12] Rate Coefficient
22- 29 E8.2 cm3/s e_coeff Uncertainty in coeff
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1 A1 --- --- [(]
2 I1 --- v [0/1]? v initial state of first hydrogen molecule
3 A1 --- --- [,]
4 I1 --- j [0/9]? j initial state of first hydrogen molecule
5 A1 --- --- [)]
7 A1 --- --- [(]
8 I1 --- vp [0/1]? vp initial state of second hydrogen molecule
9 A1 --- --- [,]
10 I1 --- jp [0/9]? jp initial state of second hydrogen molecule
11 A1 --- --- [)]
13- 18 F6.2 --- a [-19.2/-16.4] Fitting parameter a
20- 24 F5.3 --- b [1.4/4.6] Fitting parameter b
26- 32 F7.4 --- c [-0.7/1.5] Fitting parameter c
34- 38 F5.3 --- d [3.3/6.2] Fitting parameter d
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 24-Nov-2016