beta. -delayed fission from /sup 256/Es/sup m/ and the level scheme of /sup 256/Fm

Journal Article · Mon May 01 00:00:00 EDT 1989 · Phys. Rev. C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.39.1866· OSTI ID:6319241

Hall, H L; Gregorich, K E; Henderson, R A; Lee, D M; Hoffman, D C; Bunker, M E; Fowler, M M; Lysaght, P; Starner, J W; Wilhelmy, J B; others, and

The 7.6-h isotope /sup 256/Es/sup m/ was produced from a 2.5-..mu..g/cm/sup 2/ target of /sup 254/Es by the (t,p) reaction. The reaction products were separated radiochemically, and the decay properties of /sup 256/Es/sup m/ were determined via ..beta..-..gamma.., ..gamma..-..gamma.., and ..beta..-fission correlation techniques. From these measurements we were able to assign 57 ..gamma.. rays to 26 levels in the daughter /sup 256/Fm. An isomeric level was observed at 1425 keV and assigned a spin and parity of 7/sup -/. This level has a t/sub 1/2/ of (70 +- 5) ns and we observed two ..beta..-delayed fissions with delay times in the proper time range to be associated with fission from this level. This gives a ..beta..-delayed fission probability of 2 x 10/sup -5/ for this level and a partial fission half-life of 0.8/sub -0.7//sup +8.8/ ms at the 95% confidence level.

• Research Organization: Nuclear Science Division, Lawrence Berkeley Laboratory, Berkeley, California 94720
• OSTI ID: 6319241
• Journal Information: Phys. Rev. C; (United States), Journal Name: Phys. Rev. C; (United States) Vol. 39:5; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

652020* -- Nuclear Properties & Reactions
A=220 & above
Experimental
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ANGULAR MOMENTUM
BARYONS
BETA DECAY
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHARGED-PARTICLE REACTIONS
CHEMISTRY
COINCIDENCE SPECTROMETRY
DECAY
DIRECT REACTIONS
EINSTEINIUM 254 TARGET
EINSTEINIUM 256
EINSTEINIUM ISOTOPES
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
ENERGY LEVELS
EVEN-EVEN NUCLEI
FERMIONS
FERMIUM 256
FERMIUM ISOTOPES
FISSION
GAMMA RADIATION
HADRONS
HALF-LIFE
HEAVY NUCLEI
HOURS LIVING RADIOISOTOPES
IONIZING RADIATIONS
ISOTOPE SEPARATION
ISOTOPES
NUCLEAR DECAY
NUCLEAR REACTIONS
NUCLEI
NUCLEONS
ODD-ODD NUCLEI
PARITY
PARTICLE PROPERTIES
PROBABILITY
PROTONS
RADIATIONS
RADIOCHEMISTRY
RADIOISOTOPES
SEPARATION PROCESSES
SPIN
STRIPPING
TARGETS
TRANSFER REACTIONS
TRITON REACTIONS