{sup 138}La-{sup 138}Ce-{sup 136}Ce nuclear cosmochronometer of the supernova neutrino process

Journal Article · Sun Jun 15 04:00:00 EDT 2008 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.77.065802· OSTI ID:21191989

Hayakawa, T ^[1]; Shizuma, T ^[1]; Kajino, T ^[2]; Ogawa, K ^[3]; Nakada, H ^[4]

---

1. Kansai Photon Science Institute, Japan Atomic Energy Agency, Kizu, Kyoto 619-0215 (Japan)
2. National Astronomical Observatory, Osawa, Mitaka, Tokyo 181-8588 (Japan)
3. RIKEN, Nishina center, Hirosawa, Wako, Saitama 351-0198 (Japan)
4. Department of Physics, Graduate School of Science, Chiba University, Inage, Chiba 263-8522 (Japan)

The {sup 138}La (T{sub 1/2}=102 Gyr)-{sup 138}Ce-{sup 136}Ce system is proposed to be used as a nuclear cosmochronometer for measuring the time elapsed from a supernova neutrino process. This chronometer is applied to examine a sample affected by a single nucleosynthesis episode as presolar grains in primitive meteorites. A feature of this chronometer is to evaluate the initial abundance ratio of {sup 136}Ce/{sup 138}Ce using an empirical scaling law, which was found in the solar abundances. We calculate the age of the sample as a function of isotopic ratios {sup 136}Ce/{sup 138}Ce and {sup 138}La/{sup 138}Ce and evaluate the age uncertainty due to theoretical and observational errors. It is concluded that this chronometer can work well for a sample with the abundance ratio of {sup 138}La/{sup 138}Ce {>=} 20 when the ratios of {sup 136}Ce/{sup 138}Ce and {sup 138}La/{sup 138}Ce are measured within the uncertainty of 20%. The availability of such samples becomes clear in recent studies of the presolar grains. We also discuss the effect of the nuclear structure to the {nu} process origin of {sup 138}La.

• OSTI ID: 21191989
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 6 Vol. 77; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CERIUM 136
CERIUM 138
ISOTOPE RATIO
LANTHANUM 138
METEORITES
NEUTRINOS
NUCLEAR STRUCTURE
NUCLEOSYNTHESIS
SCALING LAWS
SUPERNOVAE