THE ANGULAR CORRELATION OF PROMPT NEUTRONS AND FISSION FRAGMENTS IN THERMAL NEUTRON FISSION OF U$sup 23$$sup 5$

Journal Article · Sun Jan 01 00:00:00 EST 1961 · Nuclear Phys.

DOI:https://doi.org/10.1016/0029-5582(61)90148-1· OSTI ID:4027173

Ramanna, R; Chaudhry, R; Kapoor, S S; Mikke, K; Murthy, S R.S.; Rao, P N.R.

BS>The angular distributions of the prompt neutrons of specified mean energies emitted in the thermal neutron fission of U/sup 235/ are measured with respect to the direction of motion of light fragments. A combination of a gridded ionization chamber and a gas scintillation counter system using xenon gas is used to measure the energy of the fission fragments as well as their direction of motion relative to the electric field direction of the ionization chamber. A fast neutron detector is placed along the electric fielai direction to measure the energy of the prompt neutrons by time of flight technique. The distributions obtained are compared with the distributions computed on the assumption of isotropic emission of neutrons with a Maxwellian emission spectrum. It is shown that the laboratory anisotropy N(O deg )/N(9O deg ) is an increasing function of the neutron energy in the laboratory system. The laboratory angular distributions are transformed to obtain the center-of-mass angular distributions for two groups of prompt neutron emission energies. Anisotropy of the form (a + b cos/sup 2/ theta ) is indicated for prompt neutrons with emission energies greater than 1 Mev. Anisotropy of emission is discussed in terms of the possibility of the fragments acquiring a large angular momentum at the instant of scission. (auth)

• Research Organization: Atomic Energy Establishment, Trombay, India
• NSA Number: NSA-15-024336
• OSTI ID: 4027173
• Journal Information: Nuclear Phys., Vol. Vol: 25; Other Information: Orig. Receipt Date: 31-DEC-61
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

PHYSICS
ANGULAR CORRELATION
ANGULAR DISTRIBUTION
ANGULAR MOMENTUM
ANISOTROPY
BOLTZMANN EQUATION
ELECTRIC FIELDS
ENERGY
ENERGY RANGE
FAST NEUTRONS
FISSION
FISSION PRODUCTS
IONIZATION CHAMBERS
MEASURED VALUES
MOMENTUM
NEUTRON BEAMS
NEUTRON DETECTION
NEUTRON SPECTROMETERS
PROMPT NEUTRONS
SCINTILLATION COUNTERS
TARGETS
THERMODYNAMICS
URANIUM 235
VELOCITY
XENON