Study of /sup 237/Np photonuclear reactions near threshold induced by gamma rays from thermal neutron capture

Journal Article · Fri Feb 01 04:00:00 EST 1985 · Nucl. Sci. Eng.; (United States)

OSTI ID:5978418

Geraldo, L P; Ceaser, M T.F.; Vinhas, L A

The photodisintegration of /sup 237/Np has been studied using monochromatic photons produced by thermal neutron capture in several materials. The partial cross sections sigma /sub gamma,f/ ansigma /sub gamma,n/ were measured in the energy interval from 5.43 to 10.83 MeV. Analyzing the photofission data according to the liquid drop model, the height (E /sub f/ ) and the curvature (h..omega..) of the simple fission barrier were determined: E /sub f/ = (5.9 + or - 0.2) MeV and h..omega.. = (0.8 + or - 0.4) MeV. For the competition between photoneutron emission and fission (GAMMA /sub n/ /GAMMA /sub f/ ), a constant value was found (1.28 + or - 0.15) in the 6.73- to 10.83-MeV energy range. From this result the following nuclear temperatures for /sup 237/Np were extracted on bases of some models of level density: T = 0.84 + or - 0.06 MeV (Fujimoto-Yamaguchi model) and T = 0.60 + or - 0.04 MeV (constant nuclear temperature model).

• Research Organization: Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Divisao de Fisica Nuclear, Pinheiros
• OSTI ID: 5978418
• Journal Information: Nucl. Sci. Eng.; (United States), Journal Name: Nucl. Sci. Eng.; (United States) Vol. 89:2; ISSN NSENA
• Country of Publication: United States
• Language: English

Related Subjects

652015* -- Nuclear Properties & Reactions
A=220 & above
Theoretical-- Nuclear Reactions & Scattering-- (-1987)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALPHA DECAY RADIOISOTOPES
BARYONS
CAPTURE
CROSS SECTIONS
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
GAMMA RADIATION
HADRONS
HEAVY NUCLEI
IONIZING RADIATIONS
ISOTOPES
LIQUID DROP MODEL
MATHEMATICAL MODELS
MEV RANGE
MEV RANGE 01-10
NEPTUNIUM 237
NEPTUNIUM ISOTOPES
NEUTRONS
NUCLEAR MODELS
NUCLEAR REACTIONS
NUCLEI
NUCLEONS
ODD-EVEN NUCLEI
PHOTONUCLEAR REACTIONS
RADIATIONS
RADIOISOTOPES
THERMAL NEUTRONS
YEARS LIVING RADIOISOTOPES