Radiochemical studies of neutron deficient actinide isotopes

Technical Report · Sat Apr 01 04:00:00 EST 1978

DOI:https://doi.org/10.2172/6781121· OSTI ID:6781121

Williams, K E

The production of neutron deficient actinide isotopes in heavy ion reactions was studied using alpha, gamma, x-ray, and spontaneous fission detection systems. A new isotope of berkelium, /sup 242/Bk, was produced with a cross-section of approximately 10 ..mu..b in reactions of boron on uranium and nitrogen on thorium. It decays by electron capture with a half-life of 7.0 +- 1.3 minutes. The alpha-branching ratio for this isotope is less than 1% and the spontaneous fission ratio is less than 0.03%. Studies of (Heavy Ion, pxn) and (Heavy Ion, ..cap alpha..xn) transfer reactions in comparison with (Heavy ion, xn) compound nucleus reactions revealed transfer reaction cross-sections equal to or greater than the compound nucleus yields. The data show that in some cases the yield of an isotope produced via a (H.I.,pxn) or (H.I.,..cap alpha..xn) reaction may be higher than its production via an xn compound nucleus reaction. These results have dire consequences for proponents of the ''Z/sub 1/ + Z/sub 2/ = Z/sub 1+2/'' philosophy. It is no longer acceptable to assume that (H.I.,pxn) and (H.I.,..cap alpha..xn) product yields are of no consequence when studying compound nucleus reactions. No evidence for spontaneous fission decay of /sup 228/Pu, /sup 230/Pu, /sup 232/Cm, or /sup 238/Cf was observed indicating that strictly empirical extrapolations of spontaneous fission half-life data is inadequate for predictions of half-lives for unknown neutron deficient actinide isotopes.

• Research Organization: California Univ., Berkeley (USA). Lawrence Berkeley Lab.
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6781121
• Report Number(s): LBL-7714
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400103 -- Radiometric & Radiochemical Procedures-- (-1987)
400703* -- Radiochemistry & Nuclear Chemistry-- Radioisotope Production
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALPHA DETECTION
BERKELIUM 242
BERKELIUM ISOTOPES
BETA DECAY RADIOISOTOPES
CHARGED PARTICLE DETECTION
CHARGED-PARTICLE REACTIONS
CHEMICAL ANALYSIS
CROSS SECTIONS
DECAY
DETECTION
ELECTRON CAPTURE RADIOISOTOPES
FISSION
GAMMA DETECTION
HALF-LIFE
HEAVY ION REACTIONS
HEAVY NUCLEI
ISOTOPE PRODUCTION
ISOTOPES
MINUTES LIVING RADIOISOTOPES
NEUTRON-DEFICIENT ISOTOPES
NUCLEAR REACTIONS
NUCLEI
ODD-ODD NUCLEI
RADIATION DETECTION
RADIOCHEMICAL ANALYSIS
RADIOISOTOPES
SPONTANEOUS FISSION
X-RAY DETECTION