Differential cross section for neutron scattering from {sup 209}Bi at 37 MeV and the weak particle-core coupling

• Published in: Physical review. C, Nuclear physics Vol. 82; no. 2
• Main Authors: Zhou Zuying, Ruan Xichao, Du Yanfeng, Qi Bujia, Tang Hongqing, Xia Haihong, Walter, R. L., Braun, R. T., Howell, C. R., Tornow, W., Weisel, G. J., Dupuis, M., Delaroche, J. P., Chen Zemin, Chen Zhenpeng, Chen Yingtang, Department of Physics, Duke University, Durham, North Carolina 27708, CEA, DAM, DIF, F-91297 Arpajon, Department of Physics, Tsinghua University, Beijing 100084
• Format: Journal Article
• Language: English
• Published: United States 15-08-2010
• Subjects: APPROXIMATIONS; BEAMS; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; BISMUTH 209; BISMUTH ISOTOPES; BORN APPROXIMATION; CALCULATION METHODS; CHARGED-PARTICLE REACTIONS; CHINESE ORGANIZATIONS; CIAE; COHERENT SCATTERING; COUPLING; CROSS SECTIONS; DEUTERON BEAMS; DEUTERON REACTIONS; DIFFERENTIAL CROSS SECTIONS; DIFFRACTION; DWBA; EMISSION; ENERGY RANGE; EVEN-EVEN NUCLEI; FORECASTING; HEAVY NUCLEI; HELIUM 4; HELIUM ISOTOPES; HYDROGEN ISOTOPES; INELASTIC SCATTERING; ION BEAMS; ISOTOPES; LIGHT NUCLEI; MATHEMATICAL MODELS; MEASURING INSTRUMENTS; MEV RANGE; MEV RANGE 10-100; NATIONAL ORGANIZATIONS; NEUTRON DIFFRACTION; NEUTRON EMISSION; NEUTRON SOURCES; NUCLEAR PHYSICS AND RADIATION PHYSICS; NUCLEAR REACTIONS; NUCLEI; ODD-EVEN NUCLEI; OPTICAL MODELS; PARTICLE SOURCES; RADIATION SOURCES; RADIOISOTOPES; SCATTERING; SPECTROMETERS; STABLE ISOTOPES; SURFACES; TIME-OF-FLIGHT METHOD; TRITIUM; YEARS LIVING RADIOISOTOPES
• ISSN: 0556-2813; 1089-490X
• DOI: 10.1103/PHYSREVC.82.024601

Differential scattering cross-section data have been measured at 43 angles from 11 deg. to 160 deg. for 37-MeV neutrons incident on {sup 209}Bi. The primary motivation for the measurements is to address the scarcity of neutron scattering data above 30 MeV and to improve the accuracy of optical-model predictions at medium neutron energies. The high-statistics measurements were conducted at the China Institute of Atomic Energy using the {sup 3}H(d,n){sup 4}He reaction as the neutron source, a pulsed deuteron beam, and time-of-flight (TOF) techniques. Within the resolution of the TOF spectrometer, the measurements included inelastic scattering components. The sum of elastic and inelastic scattering cross sections was computed in joint optical-model and distorted-wave Born approximation calculations under the assumption of the weak particle-core coupling. The results challenge predictions from well-established spherical optical potentials. Good agreement between data and calculations is achieved at 37 MeV provided that the balance between surface and volume absorption in a recent successful model [A. J. Koning and J. P. Delaroche, Nucl. Phys. A 713, 231 (2003)] is modified, thus suggesting the need for global optical-model improvements at medium neutron energies.