Production ratio of meta-stable isomer in {sup 180}Ta by neutrino-induced reactions

Journal Article · Wed May 12 00:00:00 EDT 2010 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3442602· OSTI ID:21362022

Hayakawa, Takehito ^[1]; Kajino, Toshitaka ^[2]; Chiba, Satoshi ^[3]; Mathews, Grant ^[4]

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1. Japan Atomic Energy Agency, Kizugawa, Kyoto 619-0215 (Japan)
2. National Astronomical Observatory, Osawa, Mitaka, Tokyo 181-8588 (Japan)
3. Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-11 (Japan)
4. Astrophysics, Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States)

The nucleosynthesis of {sup 180}Ta has remained an unsolved problem and as its origin many nucleosynthesis mechanisms have been proposed. This isotope has the unique feature that the naturally occurring abundance of {sup 180}Ta is actually a meta-stable isomer (half-life of >=10{sup 15} yr), while the ground state is a 1{sup +} unstable state which beta-decays with a half-life of only 8.15 hr. We have made a new time-dependent calculation of {sup 180}Ta meta-stable isomer residual ratio after supernova neutrino-induced reactions. This isomer residual ratio is crucial for understanding the production and survival of this naturally occurring rare isotope. We have constructed a new model under temperature evolution after type II supernova explosion. We include the explicit linking between the isomer and all known excited states and found that the residual ratio is insensitive to astrophysical parameters such as neutrino energy spectrum, explosion energy, decay time constant. We find that the explicit time evolution of the synthesis of {sup 180}Ta avoids the overproduction relative to {sup 138}La for a neutrino process neutrino temperature of 4 MeV.

• OSTI ID: 21362022
• Journal Information: AIP Conference Proceedings, Vol. 1235, Issue 1; Conference: 7. Japan-China joint nuclear physics symposium, Tsukuba (Japan), 9-13 Nov 2009; Other Information: DOI: 10.1063/1.3442602; (c) 2010 American Institute of Physics; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ABUNDANCE
ASTROPHYSICS
BETA DECAY
ENERGY SPECTRA
EVOLUTION
EXCITED STATES
GROUND STATES
HALF-LIFE
ISOMERS
LANTHANUM 138
MEV RANGE 01-10
NEUTRINO-NUCLEON INTERACTIONS
NEUTRINOS
NUCLEAR EXPLOSIONS
NUCLEOSYNTHESIS
TANTALUM 180
TIME DEPENDENCE
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
DECAY
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTARY PARTICLES
ENERGY LEVELS
ENERGY RANGE
EXPLOSIONS
FERMIONS
HOURS LIVING RADIOISOTOPES
INTERACTIONS
INTERMEDIATE MASS NUCLEI
ISOTOPES
LANTHANUM ISOTOPES
LEPTON-BARYON INTERACTIONS
LEPTON-HADRON INTERACTIONS
LEPTON-NUCLEON INTERACTIONS
LEPTONS
MASSLESS PARTICLES
MEV RANGE
NUCLEAR DECAY
NUCLEI
ODD-ODD NUCLEI
PARTICLE INTERACTIONS
PHYSICS
RADIOISOTOPES
RARE EARTH NUCLEI
SPECTRA
SYNTHESIS
TANTALUM ISOTOPES
YEARS LIVING RADIOISOTOPES