Cross-section measurement and analysis for the {sup 149}Sm(n,alpha){sup 146}Nd reaction at 6.0 MeV

Journal Article · Thu Jul 15 00:00:00 EDT 2010 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.82.014601· OSTI ID:21389194

Gledenov, Yu M; Sedysheva, M V ^[1]; Guohui, Zhang; Jiaming, Liu; Hao, Wu; Xiang, Liu; Jinxiang, Chen ^[2]; Khuukhenkhuu, G ^[3]; Szalanski, P J ^[4]; Koehler, P E ^[5]

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1. Frank Laboratory of Neutron Physics, JINR, Dubna 141980 (Russian Federation)
2. State Key Laboratory of Nuclear Physics and Technology, Institute of Heavy Ion Physics, Peking University, Beijing 100871 (China)
3. Nuclear Research Centre, National University of Mongolia, Ulaanbaatar (Mongolia)
4. Institute of Physics, University of Lodz (Poland)
5. Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

We have measured the {sup 149}Sm(n,alpha){sup 146}Nd cross section at 6.0 MeV to be 0.12+-0.018 mb. This is the first reported result for this cross section in the MeV region and so should be helpful for constraining nuclear data evaluations (which differ by a factor of 40 for this reaction at this energy) and for testing and improving nuclear models. The experiment was performed at the at the 4.5-MV Van de Graaff accelerator of Peking University. Neutrons were produced via the {sup 2}H(d,n){sup 3}He reaction using a deuterium gas target, and absolute neutron flux was determined with a small {sup 238}U fission chamber. Alpha particles were detected using a two-section gridded ionization chamber in which two large-area {sup 149}Sm{sub 2}O{sub 3} samples were placed back-to-back so that the cross section and forward/backward ratio were measured for nearly the entire 4pi solid angle. The data were compared to statistical-model predictions using the code talys. Good agreement between the measured and theoretical cross sections could be obtained with a small modification of the alpha-optical potential parameters from their default values in talys. However, we were not able to reproduce the measured forward/backward ratio. In addition, using the previously reported {sup 147}Sm(n,alpha){sup 144}Nd cross section at 6.0 MeV together with our new result, good agreement was found between the measured and predicted cross-section ratio for these two isotopes. Finally, none of the existing evaluated data libraries are in agreement with our new data to within the experimental uncertainties.

• OSTI ID: 21389194
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 82, Issue 1; Other Information: DOI: 10.1103/PhysRevC.82.014601; (c) 2010 The American Physical Society; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALPHA DECAY
ALPHA DETECTION
ALPHA PARTICLES
CROSS SECTIONS
DEUTERIUM TARGET
FISSION CHAMBERS
FORECASTING
HELIUM 3
MEV RANGE 01-10
NEODYMIUM 144
NEODYMIUM 146
NEUTRON FLUX
NEUTRON REACTIONS
NEUTRONS
NUCLEAR MODELS
SAMARIUM 147 TARGET
SAMARIUM 149 TARGET
STATISTICAL MODELS
URANIUM 238
VAN DE GRAAFF ACCELERATORS
ACCELERATORS
ACTINIDE NUCLEI
ALPHA DECAY RADIOISOTOPES
BARYON REACTIONS
BARYONS
CHARGED PARTICLE DETECTION
CHARGED PARTICLES
DECAY
DETECTION
ELECTROSTATIC ACCELERATORS
ELEMENTARY PARTICLES
ENERGY RANGE
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FERMIONS
HADRON REACTIONS
HADRONS
HEAVY NUCLEI
HELIUM ISOTOPES
INTERMEDIATE MASS NUCLEI
IONIZATION CHAMBERS
IONIZING RADIATIONS
ISOTOPES
LIGHT NUCLEI
MATHEMATICAL MODELS
MEASURING INSTRUMENTS
MEV RANGE
NEODYMIUM ISOTOPES
NEUTRON DETECTORS
NUCLEAR DECAY
NUCLEAR REACTIONS
NUCLEI
NUCLEON REACTIONS
NUCLEONS
RADIATION DETECTION
RADIATION DETECTORS
RADIATION FLUX
RADIATIONS
RADIOISOTOPES
RARE EARTH NUCLEI
SPONTANEOUS FISSION RADIOISOTOPES
STABLE ISOTOPES
TARGETS
URANIUM ISOTOPES
YEARS LIVING RADIOISOTOPES