NEUTRON-CAPTURE GAMMA RAYS OF BROMINE, COPPER, IRIDIUM, NICKEL, AND TUNGSTEN

Journal Article · Wed Aug 01 04:00:00 EDT 1962 · Dissertation Abstr.

OSTI ID:4788184

Treado, P A

Investigations were undertaken to obtain information about the formation and decay of nuclei occurring as the products in neutron-capture reactions. Samples of natural bromine, copper, iridium, nickel, and tungsten, and separated isotope, samples of Br/sup 79/, Br/sup 81/, Ni/sup 58/, Ni/sup 60/ , Ni/sup 62/, W/sup 182/, W/sup 184/, and W/sup 186/, were placed in a neutron beam and their neutron-capture gamma-ray spectra obtained. The energies and intensities of about 100 gamma-ray lines were determined from the spectra. If it is assumed that the maximum observed gamma ray energy for each isotope corresponds to a transition from the capture state to the ground state, then the energy of the transition is equal to the neutron binding energy in the product nucleus. In this way the neutron binding energies were determined. The general shape of the bromine and iridium spcctra was in qualitative agreement with that predicted from a statistical model of the nucleus. Intense high-energy lines were observed from the copper, nickel, and tungsten samples, indicating that a direct capture mechanism contributed to the neutroncapture cross section. Also, there was a correlation between the intensities of the high energy lines from copper and nickel and those of the proton groups leading to the same final state in the corresponding (d,p) reaction. The principal contributions to the background were: gamma rays independent of the sample, reactor gamma rays scattered by the sample, and capture gamma rays arising from neutrons scattered by the sample. Experiments were carried out to determine the magnitude and shape of each of the contributions, from which a background spectrum appropriate to each sample was constructed. In supplementary experiments the inherent electronic instability of the detection system was investigated and minimized; the ratio of the neutron flux to gamma-ray flux was measured and optimized: and the efficiency and resolution of the three-crystal spectrometer were determined.

• Research Organization: Univ. of Michigan, Ann Arbor
• NSA Number: NSA-16-033819
• OSTI ID: 4788184
• Journal Information: Dissertation Abstr., Journal Name: Dissertation Abstr. Vol. Vol: 23
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BACKGROUND
BINDING ENERGY
BROMINE
BROMINE 79
BROMINE 81
CAPTURE
COLLECTIVE MODEL
COPPER
CRYSTALS
DECAY
EFFICIENCY
ENERGY LEVELS
GAMMA RADIATION
IRIDIUM
IRRADIATION
MEASURED VALUES
NEUTRON BEAMS
NEUTRON FLUX
NEUTRONS
NICKEL
NICKEL 58
NICKEL 60
NICKEL 62
NUCLEAR MODELS
PHYSICS
PRODUCTION
RESOLUTION
SPECTRA
SPECTROMETERS
STATISTICS
TRANSITIONS
TUNGSTEN
TUNGSTEN 182
TUNGSTEN 184
TUNGSTEN 186