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Context.Accurate42Ti(p,γ)43V reaction rates are crucial for understanding the nucleosynthesis path of the rapid capture process (rpprocess) that occurs in X-ray bursts. Aims.We aim to improve the thermonuclear rates of42Ti(p,γ)43V based on more complete resonance information and a more accurate direct component, together with the recently released nuclear masses data. We also explore the impact of the newly obtained rates on therpprocess. Methods.We reevaluated the reaction rate of42Ti(p,γ)43V by the sum of the isolated resonance contribution instead of the Hauser-Feshbach statistical model. We used a Monte Carlo method to derive the associated uncertainties of new rates. The nucleosynthesis simulations were performed via the NuGrid post-processing code ppn. Results.The new rates differ from previous estimations due to the use of a series of updated resonance parameters and a direct S factor. Compared with the previous results from the Hauser-Feshbach statistical model, which assumes compound nucleus43V with a sufficiently high-level density in the energy region of astrophysical interest, large differences exist over the entire temperature region ofrp-process interest, up to two orders of magnitude. We consistently calculated the photodisintegration rate using our new nuclear masses via the detailed balance principle, and found the discrepancies among the different reverse rates are much larger than those for the forward rate, up to ten orders of magnitude at the temperature of 108K. Using a trajectory with a peak temperature of 1.95×109K, we performed therp-process nucleosynthesis simulations to investigate the impact of the new rates. Our calculations show that the adoption of the new forward and reverse rates result in abundance variations for Sc and Ca of 128% and 49%, respectively, compared to the variations for the statistical model rates. On the other hand, the overall abundance pattern is not significantly affected. The results of using new rates also confirm that therp-process path does not bypass the isotope43V. Conclusions.Our study found that the Hauser-Feshbach statistical model is inappropriate to the reaction rate evaluation for42Ti(p,γ)43V. The adoption of the new rates confirms that the reaction path of42Ti(p,γ)43V(p,γ)44Cr(β+)44V is a key branch of therpprocess in X-ray bursts.
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Study of the 44 Ti(α, p) 47 V reaction rate using high-precision 50 Cr(p, t) 48 Cr measurements
Abstract The abundance and distribution of44Ti tells us about the nature of the core-collapse supernovae explosions. There is a need to understand the nuclear reaction network creating and destroying44Ti in order to use it as a probe for the explosive mechanism. The44Ti(α, p)47V reaction is a very important reaction and it controls the destruction of44Ti. Difficulties with direct measurements have led to an attempt to study this reaction indirectly. Here, the first step of the indirect study which is the identification of levels of the compound nucleus48Cr is presented. A 100-MeV proton beam was incident on a50Cr target. States in48Cr were populated in the50Cr(p, t)48Cr reaction. The tritons were momentum-analysed in the K600 Q2D magnetic spectrometer at iThemba LABS.
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- PAR ID:
- 10489434
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Journal of Physics
- Date Published:
- Journal Name:
- Journal of Physics: Conference Series
- Volume:
- 2586
- Issue:
- 1
- ISSN:
- 1742-6588
- Page Range / eLocation ID:
- 012106
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1088/1742-6596/2586/1/012106
