PROGRESS REPORT FOR APRIL, MAY, JUNE 1958 TO THE UNITED STATES ATOMIC ENERGY COMMISSION

Technical Report · Sat Oct 31 04:00:00 EST 1959

OSTI ID:4292674

Neutron Physics. The Nevis neutron velocity spectrometer was used to obtain more data on resonance levels in U/sup 235/. The "flat detector" for the velocity selector wss tested on the Nevis cyclotron, A new highpressure gas scintillation chamber is described. Helium-3 proportional counter development continued. Improvements on the Columbin neutron crystal spectrometer are discussed. The neutron-reflecting properties of Ge are investigated. The absolute fission cross section of U/sup 235/ was measured as 581 plus or minus 7 barns at 0.0253 ev. The stoichiometry of yttrium hydrides was studied. Charged Particle Investigations. Cyclotron modifications are reported. Experiments to determine the ground state of F/sup 20/ and a 22-Mev excited state in He/sup 4/ are described. The intermediate image pair spectrometer was used to measure pairs from monopole and gamma transitions in several light nuclei. Gamma transitions in O/sup 16/ were investigated. Data are given for gamma energies from deuteron bombardment of Al/sup 27/ and Na/sup 23/. Alpha elastic scattering by O/sup 16/ and proton capture in N/sup 15/ were studied, The Ne/sup 20/(dn)Na/ sup 21/ reaction was studied to find the levels in Na/sup 21/ and assign spins and parities. Steering magnet and magnet regulator construction for the Van de Graaff generator is reported. Construction of a 19-ft thermal diffusion column is described. Instrument Development. Design studies of a multichannel annlyzer for the double-focusing reaction product spectrometer are reported. A pulse- height selector is described which is for use with the 2000-channel velocity spectrometer. Design work on the Van de Graaff scattering chamber drives is discussed, and brief reports of other instrument work are made. The circular polarization of Co/sup 60/ gamma rays was measured. Internal bremsstrahlung from Fe/sup 55/ was studied. A beta recoil experiment on He/sup 6/ is discussed. The ft value for Ca/sup 39/ was studied. (For preceding peried see CU-174.) (T.R.H.)

• Research Organization: Columbia Univ., New York. Pupin Cyclotron Lab.; Columbia Univ., New York. George B. Pegram Lab.
• NSA Number: NSA-13-005651
• OSTI ID: 4292674
• Report Number(s): CU-176
• Country of Publication: United States
• Language: English

Related Subjects

ALPHA BEAMS-- ALPHA PARTICLES-- MEASURED VALUES-- NUCLEAR REACTIONS-- OXYGEN-- OXYGEN 16-- SCATTERING
ALUMINUM 27-- DEUTERON BEAMS-- ENERGY LEVELS-- ENERGY RANGE-- GAMMA RADIATION-- MEASURED VALUES- - NUCLEAR REACTIONS-- SODIUM 23
BETA DECAY-- CALCIUM 39-- HALF-LIFE-- NUMERICALS
BETA DECAY-- HELIUM 6-- MEASURED VALUES-- RECOILS
BETA SPECTROMETERS-- ENERGY LEVELS-- GAMMA RADIATION-- GAMMA SPECTROMETERS-- IMAGES-- MASS-- MEASURED VALUES-- NUCLEI-- PAIR PRODUCTION- - PAIR SPECTROMETERS
BREMSSTRAHLUNG-- INTERNAL CONVERSION-- IRON 55
CAPTURE-- DECAY-- GAMMA RADIATION-- MEASURED VALUES-- NITROGEN 15-- OXYGEN 16-- PROTON BEAMS-- RADIATIONS
CO
PHYSICS AND MATHEMATICS