J/A+A/513/A61 Neutron-induced astrophysical reaction rates (Panov+, 2010)
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Neutron-induced astrophysical reaction rates for translead nuclei.
Panov I.V., Korneev I.Yu., Rauscher T., Martinez-Pinedo G., Kelic-Heil A.,
Zinner N.T., Thielemann F.-K.
=2010A&A...513A..61P (SIMBAD/NED BibCode)
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ADC_Keywords: Atomic physics
Keywords: nuclear reactions, nucleosynthesis, abundances - supernovae: general -
stars: neutron
Abstract:
Neutron-induced reaction rates, including fission, are calculated in
the temperature range 10^8^<=T(K)<=10^10^ within the framework of the
statistical model for targets with atomic number 84<=Z<=118 (from Po
to Uuo) from the neutron to the proton drip-line. Four sets of rates
have been calculated, utilizing - where possible - consistent nuclear
data for neutron separation energies and fission barriers from
Thomas-Fermi (TF), Extended Thomas-Fermi plus Strutinsky Integral
(ETFSI), Finite-Range Droplet Model (FRDM) and Hartree-Fock-Bogolyubov
(HFB) predictions. Tables of calculated values as well as analytic
seven parameter fits in the standard REACLIB format are supplied. We
also discuss the sensitivity of the rates to the input, aiming at a
better understanding of the uncertainties introduced by the nuclear
input.
Description:
The organization of Tables 3-6 with calculated rates for 24 different
values of T_9_ is extremely simple - all data are in 8 columns. The
columns give, in this order, the target element, the atomic mass
number A of the target, the temperature in T_9_, partition function of
the target, neutron-induced fission rate for the ground state,
neutron-induced fission rate with thermally populated target states,
neutron capture rate for the ground state, neutron capture rate with
thermally populated target states.
The rates in Tables 3-6 were calculated on the basis of different mass
and fission barrier predictions: ETFSI, TF and
FRDM(masses)+TF(barriers), respectively (see main text of the paper
for details).
The fitting coefficients for the (n,g), (g,n), and neutron-induced
fission rates (n,f) with different mass and fission-barrier
predictions are placed in the Tables 7-18 (see example on how to use
them in Appendix A of the main paper). The columns in Tables 7-18 are
organized as follows: target element, atomic mass number A of the
target, target charge number Z, the number of fitting curves i_{fit},
seven coefficients of the forward reaction a_i, and the mean square
error for direct reactions.
A value i_{fit}_=0 means that there is only one seven-parameter set to
fit the rate. Values i_{fit}>1 give the number of parameter sets which
have to be added up to yield the final rate, i.e. the rate r is
calculated as r={sum.on.i}r_i_, with each r_i_ computed from the i-th
parameter set and using Eq.
r_i_=exp(a0+a1/T9+a2/T9^1/3^+a3*T9^1/3^+a4*T9+a5*T9^5/3^+a6*ln(T9)) (4).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 81 64032 (n,g) and (n,f) rates with ETFSI-predictions
table4.dat 81 71760 (n,g) and (n,f) rates with TF-predictions
table5.dat 81 70056 (n,g) and (n,f) rates with FRDM+TF-predictions
table6.dat 81 31728 (n,g) and (n,f) rates with HFB14-predictions
table7.dat 124 2662 Coefficients for (n,g)-rate fit, ETFSI
table8.dat 124 2984 Coefficients for (n,g)-rate fit, TF
table9.dat 124 2911 Coefficients for (n,g)-rate fit, FRDM+TF
table10.dat 124 1468 Coefficients for (n,g)-rate fit, HFB14
table11.dat 114 2414 Coefficients for (g,n)-rate fit, ETFSI
table12.dat 114 2948 Coefficients for (g,n)-rate fit, TF
table13.dat 114 2875 Coefficients for (g,n)-rate fit, FRDM+TF
table14.dat 114 1436 Coefficients for (g,n)-rate fit, HFB14
table15.dat 124 3288 Coefficients for (n,f)-rate fit, ETFSI
table16.dat 124 3928 Coefficients for (n,f)-rate fit, TF
table17.dat 124 3846 Coefficients for (n,f)-rate fit, FRDM+TF
table18.dat 124 1448 Coefficients for (n,f)-rate fit, HFB14
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Byte-by-byte Description of file (#): table[3456].dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- El Target element (corresponding to Z)
5- 7 I3 --- A Atomic mass number of the target
9- 11 I3 --- Z [84,118] Charge number of the target
15- 19 F5.2 GK T9 [0.10/10.00] Temperature
25- 33 E9.4 --- pf Partition function of the target
37- 46 E10.4 cm3/s/mol nf Neutron-induced fission rate for ground state
49- 58 E10.4 cm3/s/mol nf* Neutron-induced fission rate with thermally
populated target states
61- 69 E9.4 cm3/s/mol ng Neutron capture rate for the ground state
73- 81 E9.4 cm3/s/mol ng* Neutron capture rate with thermally
populated target states
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Byte-by-byte Description of file (#): table[789].dat table1?.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- El Target element (corresponding to Z)
5- 7 I3 --- A Atomic mass number of the target
10- 12 I3 --- Z [84,118] Charge number of the target
15 I1 --- i [0/1] Number of fitting curve (1)
18- 30 E13.7 --- a0 Coefficient a0 of the forward reaction r_i_ (1)
32- 44 E13.7 --- a1 Coefficient a1 of the forward reaction r_i_ (1)
46- 58 E13.7 --- a2 Coefficient a2 of the forward reaction r_i_ (1)
60- 72 E13.7 --- a3 Coefficient a3 of the forward reaction r_i_ (1)
74- 86 E13.7 --- a4 Coefficient a4 of the forward reaction r_i_ (1)
88-100 E13.7 --- a5 Coefficient a5 of the forward reaction r_i_ (1)
102-114 E13.7 --- a6 Coefficient a6 of the forward reaction r_i_ (1)
118-124 E7.2 --- zeta ? Mean square error for direct reactions (Eq.(5))
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Note (1): The rate r is calculated as r={Sum}r_i_, and each r_i_ is computed as
r_i_ = exp(a0+a1/T9+a2/T9^1/3^+a3*T9^1/3^+a4*T9+a5*T9^5/3^+a6*ln(T9)).
When i=0, there is a single seven-parameter set to fit the rate.
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Acknowledgements:
Igor Panov, Igor.Panov(at)itep.ru
References:
Panov, Kolbe, Pfeiffer, Rauscher, Kratz, & Thielemann, 2005NuPhA.747..633P
Calculations of fission rates for r-process nucleosynthesis
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(End) Igor Panov [ITEP, Russia], Patricia Vannier [CDS] 21-Jan-2010