RADIATIONS OF $sup 93$Y AND $sup 94$Y AND HALF-LIVES OF $sup 93$Sr AND $sup 94$Sr

Journal Article · Fri May 01 04:00:00 EDT 1959 · J. Inorg. & Nuclear Chem.

DOI:https://doi.org/10.1016/0022-1902(59)80113-5· OSTI ID:4238601

Knight, J D; Hoffman, D C; Dropesky, B J; Frasco, D L

The radiations of Y/sup 93/ and Y/sup 94/ have been examined by BETA - ray spectrometry and gamma -ray scintillation spectrometry. Y/sup 93/ decays about 90 per cent by a 2.89 plus or minus 0.02-Mev BETA transitlon to the ground state of Zr/sup 93/; the spectrum of the 2.89 Mev group has a unique first- forbidden shape. Gamma rays of energies 0.267, 0.49, 0.665, 0.935, 1.15, company the remaining 10 per cent of the disintegrations. On the basis of gamma gamma coincidence measurements, these radiations have been fitted to a partial decay scheme involving levels in Zr/sup 93/ at 0.267, 0.935, 1.42, trum of maximum energy 5.0 plus or minus 0.2 Mev; the highestenergy group corresponds to the transition to the ground state of Zr/sup 94/. The lower-energy BETA transitions are accompanied by gamma rays of energies of 0.56, 0.92, 1.13, 1.65, groups at 2.57 and 3.06 Mev. The half lives of Sr/sup 93/ and Sr/sup 94/, measured by experiments involving periodic chemical separations of Y/sup 93/ and Y/sup 94/ from fissionproduct strontium, are 8.2 plus or minus 0.5 min and 1.3 plus or minus 0.2 min, respectively. The half lives of Y/sup 93/ and Y/sup 94/ are 10.25 plus or minus 0.10 hr and 20 plus or minus 1 min, respectively. A search has been made for isomerism in Y/sup 93/. Measurements on yttrium grown from fission-product strontium have shown no definite evidence for an isomer of Y/ sup 93/ with a half life in the range 30 sec to 3 hr. The yield of 10.25 hr Y/ sup 93/ from fission of U/sup 235/ by water-moderated pile'' neutrons is (6. 1 plus or minus 0.6) per cent. (auth)

• Research Organization: Los Alamos Scientific Lab., N. Mex.
• NSA Number: NSA-13-018510
• OSTI ID: 4238601
• Journal Information: J. Inorg. & Nuclear Chem., Journal Name: J. Inorg. & Nuclear Chem. Vol. Vol: 10
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BETA PARTICLES
BETA SPECTROMETERS
CHEMICAL REACTIONS
COINCIDENCE METHODS
DECAY
EFFICIENCY
ENERGY LEVELS
FISSION PRODUCTS
GAMMA SPECTROMETERS
HALF-LIFE
ISOMERS
ISOTOPE SEPARATION
MEASURED VALUES
NEUTRONS
PHYSICS AND MATHEMATICS
RADIATIONS
REACTORS
SCINTILLATION COUNTERS
SPECTRA
STRONTIUM
STRONTIUM 93
STRONTIUM 94
URANIUM 235
WATER MODERATOR
YTTRIUM 93
YTTRIUM 94