J/ApJ/726/25 Production of the p-process nuclei in SNe Ia (Kusakabe+, 2011)
Production of the p-process nuclei in the carbon-deflagration model for type Ia
supernovae.
Kusakabe M., Iwamoto N., Nomoto K.
<Astrophys. J., 726, 25 (2011)>
=2011ApJ...726...25K 2011ApJ...726...25K
ADC_Keywords: Supernovae ; Abundances ; Atomic physics ; Models
Keywords: Galaxy: abundances - nuclear reactions, nucleosynthesis, abundances -
supernovae: general
Abstract:
We calculate the nucleosynthesis of proton-rich isotopes in the
carbon-deflagration model for Type Ia supernovae (SNe Ia). The seed
abundances are obtained by calculating the s-process nucleosynthesis
that is expected to occur in the repeating helium shell flashes on the
carbon-oxygen (CO) white dwarf (WD) during mass accretion from a
binary companion. When the deflagration wave passes through the outer
layer of the CO WD, p-nuclei are produced by photodisintegration
reactions on s-nuclei in a region where the peak temperature ranges
from 1.9 to 3.6x109K. We confirm the sensitivity of the p-process on
the initial distribution of s-nuclei. We show that the initial C/O
ratio in the WD does not affect much the yield of p-nuclei. On the
other hand, the abundance of 22Ne left after s-processing has a
large influence on the p-process via the 22Ne(α,n) reaction.
We find that about 50% of p-nuclides are co-produced when normalized
to their solar abundances in all adopted cases of seed distribution.
Mo and Ru, which are largely underproduced in Type II supernovae (SNe
II), are produced more than in SNe II although they are underproduced
with respect to the yield levels of other p-nuclides. The ratios
between p-nuclei and iron in the ejecta are larger than the solar
ratios by a factor of 1.2. We also compare the yields of oxygen, iron,
and p-nuclides in SNe Ia and SNe II and suggest that SNe Ia could make
a larger contribution than SNe II to the solar system content of
p-nuclei.
Description:
In this paper, we have adopted a carbon-deflagration model (W7) for SN
Ia (Nomoto et al. 1984ApJ...286..644N 1984ApJ...286..644N) and analyzed the p-process
nucleosynthesis.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 20 247 *Initial mass fractions X of seed nuclei for Case A
table2.dat 20 235 *Initial mass fractions X of seed nuclei for Case B
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Note on table1.dat and table2.dat: In this investigation, we assume two sets of
initial seed abundances with mean neutron exposure τ0=0.15 (Case A) and
0.33mb-1 (Case B) for the p-process.
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Byte-by-byte Description of file: table[12].dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- El Nuclide element (Z)
3- 5 I3 --- A [1/209] Nuclide isotope (A)
8- 20 E13.7 --- Abundance Initial mass fraction
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 16-Aug-2012