Neutron capture and total cross sections for /sup 48/Ca: astrophysical implications
Attempts to understand abundance anomalies of the Ca isotopes in the Allende meteorite via the n..beta..-process require 30-keV Maxwellian averaged capture cross sections. Experimental data on /sup 48/Ca in this energy region of astrophysical significance is important since a single resonance in this vicinity could dominate the capture cross section. Neutron capture and total cross section measurements have been performed at ORELA on a 9.97-g sample of CaCO/sub 3/, enriched to 96% /sup 48/Ca, over the energy ranges 10 eV to 500 keV (sigma/sub ..gamma../) and 10 keV to 4MeV (sigma/sub T/). Only two small resonances were found for /sup 48/ Ca in the 30-keV energy region (at 19.3 and 106.9 keV) and those only in capture. Their contribution to the 30-keV-averaged cross section is only 50 ..mu..b compared to 1.0 mb calculated from direct capture. The p-wave strength and large d/sub 5/2/ strength observed above 150 keV do not contribute significantly to the 30 keV capture.
- Research Organization:
- Middle Tennessee State Univ., Murfreesboro (USA); Oak Ridge National Lab., TN (USA)
- DOE Contract Number:
- AC05-84OR21400; AS05-80ER10710
- OSTI ID:
- 6395745
- Report Number(s):
- CONF-840906-2; ON: DE85001759
- Resource Relation:
- Conference: Capture gamma-ray spectroscopy conference, Knoxville, TN, USA, 10 Sep 1984
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
CALCIUM 48 TARGET
NEUTRON REACTIONS
METEORITES
CHEMICAL COMPOSITION
CAPTURE
TOTAL CROSS SECTIONS
CALCIUM
EV RANGE
EXPERIMENTAL DATA
ISOTOPE RATIO
KEV RANGE
MEV RANGE 01-10
RESONANCE
ALKALINE EARTH METALS
BARYON REACTIONS
CROSS SECTIONS
DATA
ELEMENTS
ENERGY RANGE
HADRON REACTIONS
INFORMATION
METALS
MEV RANGE
NUCLEAR REACTIONS
NUCLEON REACTIONS
NUMERICAL DATA
TARGETS
651525* - Nuclear Properties & Reactions
A=39-58
Experimental- Nuclear Reactions & Scattering- (-1987)