J/A+A/342/881 Uncertainties in r-abundance distribution (Goriely 1999)
Uncertainties in the solar system r-abundance distribution
Goriely S.
<Astron. Astrophys. 342, 881 (1999)>
=1999A&A...342..881G 1999A&A...342..881G
ADC_Keywords: Atomic physics
Keywords: nuclear reactions, nucleosynthesis, abundances - Sun: abundances -
solar system: general - stars: abundances
Description:
Tables 1&2 correspond to the first estimate of the error factors
affecting the β decay rates of highly ionized heavy atoms in
stellar environments. The uncertainties in the stellar β-decay
and EC rates strongly depend on the relevance of the experimentally
unknown transitions at a given temperature and density and the
reliability of their evaluated probability. To estimate the
temperature- and density-dependent errors on the β-decay rates,
we have reiterated the Yokoi & Takahashi (1987, At. Data Nucl. Data
Tables 36, 375) calculation with unknown transition rates modified by
a typical error value of log(ft)=±0.5 (Takahashi 1998, private
communication). No transition faster than log(ft)=5 is permitted in
this error calculation. Newly measured transition probabilities, e.g.
the allowed transition in the 187Re bound-state β-decay (Bosch
et al., 1996PhRvL..77.5190B 1996PhRvL..77.5190B), have been considered. Minimum and
maximum error factors around the published rates of Yokoi & Takahashi
(1987) are given in Tables 1 and 2 at temperatures 1≤T8≤4 and
electronic densities (expressed in terms of 1026cm-3 of
1≤Ne≤30. When the density-dependence does not affect the final
uncertainty factor by more than 0.10 between the Ne=1 and 3 cases,
only values at Ne=10 are given in the tables. Note that an increase
of transition probability by log(ft)=0.5 gives rise to an increase of
the final rate by a maximum value of 3.16. This maximum variation is
obtained for many rates. The derived error factors are used in
parametric s-process calculations within the canonical multi-event
model to estimate their impact on the predicted s-abundance
distribution and the resulting uncertainties on the solar r-abundance
distribution.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 49 70 Minimum and maximum error factors affecting the
β- decay rates of Yokoi & Takahashi
(1987, At. Data Nucl. Data Tables 36, 375)
table2.dat 49 38 Minimum and maximum error factors affecting the
β+ and EC rates of Yokoi & Takahashi
(1987, At. Data Nucl. Data Tables 36, 375)
tables.ps 72 606 PostScript version of the tables
tables.tex 89 158 LaTeX version of the tables
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Byte-by-byte Description of file: table1.dat table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- A Atomic mass of the nucleus
5- 6 A2 --- Z Symbol the element
8- 9 I2 10+26cm-3 Ne ? Electronic number density
11- 14 F4.2 --- f1Min Minimum error factor for T=10+8K
16- 19 F4.2 --- f1Max Maximum error factor for T=10+8K
21- 24 F4.2 --- f2Min Minimum error factor for T=2*10+8K
26- 29 F4.2 --- f2Max Maximum error factor for T=2*10+8K
31- 34 F4.2 --- f3Min Minimum error factor for T=3*10+8K
36- 39 F4.2 --- f3Max Maximum error factor for T=3*10+8K
41- 44 F4.2 --- f4Min Minimum error factor for T=4*10+8K
46- 49 F4.2 --- f4Max Maximum error factor for T=4*10+8K
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Acknowledgements: Stephane Goriely
(End) Patricia Bauer [CDS] 26-Oct-1998