THE FISSION OF Th$sup 232$ BY 14-Mev NEUTRONS AND BY PHOTONS HAVING A MAXIMUM ENERGY E$gamma$ (MAX) = 90 Mev

Journal Article · Tue Oct 01 00:00:00 EDT 1963 · Doklady Akademii Nauk SSSR (U.S.S.R.) English translation currently published in a number of subject-oriented journals

OSTI ID:4136436

Komar, A P; Bochagov, B A; Fadeev, V I

The energy distribution of fission fragments at a fixed mass ratio was determined by irradiating a thin target of thorium nitrate (50 to 150 mu g/cm/ sup 2/) mounted on a collosion film sputtered with Al. A total of 18,000 to 21,000 fission events was analyzed. A contour diagram was plotted with the total kinetic energy of the paired fission fragments E, and the fission mass ratio m/ sub h//m/sub l/ (h = heavy, 1 = light) as coordinates. A hump corresponding to asymmetric fission at a mass ratio of m/sub h//m/sub l/ = 1.53 is observed along with another hump corresponding to symmetrical mass fission. The energy and mass distributions of the fission fragments were determined at various angles theta with respect to the neutron or gamma -ray beam. The total kinetic energy E at various fixed mass ratios m/sub h//m/sub i/ is given for the angular intervals of 0 to 34 deg , 34to 48 deg , 48 to 60 deg , 80 to 70 deg , and 70 to 80 deg . Two peaks in the total kinetic energy distribution are observed at a mass ratio m/sub h//m/sub l/ = 1.1 to 1.3. The positions of both peaks are shifted toward lower energies on increasing m/sub h//m/sub l/ from 1.1 to 1.3. The most probable kinetic energy of symmetrical fission at m/sub h//m/sub l/ = 1 to 1.1 is 10 Mev less thand the most probsble value of E at m/sub h// m/sub l/ = 1.3 to 1.4. It is assumed that symmetrical fission shows a smaller value of E than asymmetrical fission. The angular distribution of fission fragment from Th /sup 232/ can be described by the equation: sigma ( theta ) = 1 plus or minus Acos/sup 2/ theta , where A = 1. The angular andisotropy is sigma (0 deg )/ sigma (90 deg ) = 2. A transition from two peaks in the energy distribution E at m/sub h//m/sub l/ == theta . (TTT)

• Research Organization: Ioffe Inst. of Physics, Leningrad
• NSA Number: NSA-18-002852
• OSTI ID: 4136436
• Journal Information: Doklady Akademii Nauk SSSR (U.S.S.R.) English translation currently published in a number of subject-oriented journals, Vol. Vol: 152; Other Information: Orig. Receipt Date: 31-DEC-64
• Country of Publication: Country unknown/Code not available
• Language: Russian

Related Subjects

PHYSICS
ALUMINUM
ANGULAR DISTRIBUTION
ANISOTROPY
CELLULOSE
CONFIGURATION
DIAGRAMS
DISTRIBUTION
ENERGY
ENERGY RANGE
EQUATIONS
FILMS
FISSION
FISSION PRODUCTS
GAMMA RADIATION
IRRADIATION
MASS
MEV RANGE
NEUTRON BEAMS
ORGANIC NITROGEN COMPOUNDS
PROTON BEAMS
TARGETS
THICKNESS
THORIUM 232
THORIUM NITRATES
VELOCITY