Experimental investigation of the isomeric-shelf phenomenon in the photofission cross sections of heavy nuclei

Journal Article · Wed Nov 01 04:00:00 EST 1978 · Sov. J. Nucl. Phys. (Engl. Transl.); (United States)

OSTI ID:6179405

Zhuchko, V E; Ostapenko, Y B; Smirenkin, G N; Soldatov, A S; Tsipenyuk, Y M

Yield measurements are reported for photofission of /sup 232/Th, /sup 236/U, /sup 238/U, and /sup 237/Np in the deep sub-barrier energy region 3.5--4.6 MeV where anomalies in the cross section: isomeric shelfs: were previously observed (Phys. Rev. C, 12, 863 (1975)); Pis'ma. Zh. Eksp. Teor. Fiz. 22, 255 (1975), (JETP Lett. 22, 118 (1975)). The various sources of background arising in this energy region, which is only with difficulty accessible for measurements, are analyzed in detail. Analysis of the anomalies in the behavior of the integrated photofission yields in the case of the two nuclei /sup 236/U and /sup 238/U most favorable for study indicates a resonance nature of the cross sections for delayed fission and a substantially more complicated physics of the phenomenon than the simplified interpretation of Bowman (Phys. Rev. C, 12, 863 (1975)).

• Research Organization: Institute of Physics Problems, USSR Academy of Sciences
• OSTI ID: 6179405
• Journal Information: Sov. J. Nucl. Phys. (Engl. Transl.); (United States), Journal Name: Sov. J. Nucl. Phys. (Engl. Transl.); (United States) Vol. 28:5; ISSN SJNCA
• Country of Publication: United States
• Language: English

Related Subjects

652026* -- Nuclear Properties & Reactions
A=220 & above
Experimental-- Spontaneous & Induced Fission-- (-1987)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ABSORPTION
CROSS SECTIONS
ENERGY
FISSION
FISSION BARRIER
FISSION YIELD
NEPTUNIUM 237 TARGET
NUCLEAR POTENTIAL
NUCLEAR REACTION YIELD
NUCLEAR REACTIONS
PHOTOFISSION
PHOTONUCLEAR REACTIONS
POTENTIALS
RESONANCE ABSORPTION
TARGETS
THORIUM 232 TARGET
THRESHOLD ENERGY
URANIUM 236 TARGET
URANIUM 238 TARGET
YIELDS