INVESTIGATION OF U$sup 234$ AND U$sup 235$ $alpha$ EMISSION FINE STRUCTURE

Journal Article · Thu Sep 01 04:00:00 EDT 1960 · Izvest. Akad. Nauk S.S.S.R., Ser. Fiz.

OSTI ID:4082744

Baranov, S A; Zelenkov, A G; Kulakov, V M

A double-focusing large magnetic spectrometer with strong light and relatively high resolving power was used in the investigation of U/sup 234/ and U/ sup 235/ alpha spectrum fine str ucture. The calibration was carried out with three monoenergetic alpha -particle groups with variable energy: 6110 kev(Cm/sup 242/), 5495 kev(Pu/sup 238/, and 4768 kev(U/sup 234/. The calibration prove d suitable for the work carried out at 4150 to 4800 kev. The alpha -particle group of U/sup 234/ corresponding to the ground state of Th/sup 230/(E/sub i = 4768 kev) was used as standard. Among the three known transitions to the rotational levels of Th/sup 230/ (0/sup +/, 2/sup +/, and 4/sup +/) the level 4/ sup +/ was for the first time observed with a spectrometer. Tbe experiments observed 13 groups of alpha particles. Analysis of the data corfirms the postulate that the U/sup 235/ alpha spectrum fine structure corresponds to the transitions on the four and five singlet states of Th/sup 231/. The smallest forbiddeness coefficients are exhibited by the group alpha /sub 13/, alpha /sub 8/, alpha /sub 10/. Considering that the spin of U/sup 2/ s/sup 31/ in tbe ground state is 7/2 with a negative parity, the above groups on the Th/sup 231/ level will exhibit tbe same quantum characteristics. A scheme of energy levels for Th/sup 231/ is suggested; however, the plotted decay scheme should be considered only as probable. Some additional data on conversion electron spectra should be helpful in plotting a more accurate scheme. (R.V.J.)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-15-012109
• OSTI ID: 4082744
• Journal Information: Izvest. Akad. Nauk S.S.S.R., Ser. Fiz., Journal Name: Izvest. Akad. Nauk S.S.S.R., Ser. Fiz. Vol. Vol: 24
• Country of Publication: Country unknown/Code not available
• Language: Russian

Related Subjects

ALPHA DECAY
ALPHA DETECTION
ALPHA PARTICLES
ALPHA SPECTROMETERS
ANGULAR MOMENTUM
ATOMIC MODELS
CURIUM 242
DECAY
ENERGY LEVELS
EXCITATION
FINE STRUCTURE
MAGNETIC FIELDS
MEASURED VALUES
PARITY
PHYSICS
PLUTONIUM 238
RESOLUTION
ROTATION
SPECTRA
SPIN
STANDARDS
THORIUM 230
THORIUM 231
URANIUM 234
URANIUM 235