THE ANGULAR DISTRIBUTION OF ALPHA PARTICLES EMITTED BY ORIENTED Np$sup 237$ NUCLEI (thesis)

Technical Report · Tue May 10 04:00:00 EDT 1960

OSTI ID:4157099

Hanauer, S H; Dabbs, J W.T.; Roberts, L D; Parker, G W

Neptunium-237 nuclei were aligned when a monocrystalline sample of neptunyl rubidium nitrate was cooled to 0.2 to 4.2 deg K. The rotatable sample was placed in a capsule filled with He/sup 3/ gas for heat transfer. Also in tbe capsule were a germanium surface-barrier alpha-particle counter, a thermometer, and rotation indicators. The capsule was in thermal contact with 1/2 mole of manganous ammonium sulfate hexahydrate for cooling by adiabatic demagnetization. At all temperatures in the range studied, tbe alpha particles were observed to be emitted preferentially perpendicular to the crystalline c axis. Comparison of the temperature variation of the anisotropy with predictions from an experimentally determined spin Hamiltonian made possible an unambiguous assignment, A < O, P> O, of the signs of the hyperfine coupling constants in neptunyl rubidium nitrate. These sign assignments and the experimentally observed preferred direction for alpha-particle emission place current ideas about the electronic structure of uranyl-like ions in conflict with a simple barrierpenetration picture of alpha-particle emission. (auth)

• Research Organization: Oak Ridge National Lab., Tenn.
• DOE Contract Number: W-7405-ENG-26
• NSA Number: NSA-14-015276
• OSTI ID: 4157099
• Report Number(s): ORNL-2919
• Country of Publication: United States
• Language: English

Related Subjects

ALPHA DECAY
ALPHA DETECTION
ALPHA PARTICLES
AMMONIUM COMPOUNDS
ANGULAR DISTRIBUTION
ANISOTROPY
CONFIGURATION
CRYOGENICS
DIFFERENTIAL EQUATIONS
ELECTRONS
GERMANIUM
HAMILTONIAN
HYPERFINE STRUCTURE
INSTRUMENTS
INTERACTIONS
LATTICES
LOW TEMPERATURE
MAGNETIC FIELDS
MANGANESE SULFATES
MATHEMATICS
MEASURED VALUES
MONOCRYSTALS
NEPTUNIUM 237
NEPTUNIUM NITRATES
PERFORMANCE
PHYSICS
POLARIZATION
QUANTUM MECHANICS
ROTATION
RUBIDIUM NITRATES
SEMICONDUCTORS
SPIN
TEMPERATURE
THERMOMETERS