Nuclear properties of mendelevium

Conference · Tue Jan 01 00:00:00 EST 1980

OSTI ID:5468377

Hoffman, D C

The heavy Fm isotopes (/sup 258/Fm and /sup 259/Fm) so far appear to be unique in exhibiting very symmetric mass distributions and anomolously high fragment total kinetic energies. This effect appears to be associated with the Z = 100 proton configuration of the fissioning nuclide which can fission symmetrically into two fragments having the Z = 50 closed-proton shell configuration; /sup 256/Cf which has the same number of neutrons but only 98 protons does not exhibit these fission properties. Furthermore, /sup 259/Md, also having 158 neutrons but with 101 protons, fissions symmetrically but with a normal total kinetic energy. However, the total kinetic-energy distribution is extremely broad, indicating a range of fragment shapes at scission from spherical to highly distorted. It is extremely important to check more nuclides with Z greater than 100 and N greater than or equal to 158 to check the relative importance of the fragement proton and neutron shells. New methods are needed for measurements of half lives of ms or less and for providing positive identification of the Z and A of the fissioning species. Recent experiments indicate that /sup 259/Fm is produced with a 10 to 15 nb cross section in bombardments of /sup 248/Cm with /sup 18/O and that therefore extreme caution must be exercised in making assignments. However, transfer or deep inelastic reactions of this kind would appear to offer a good possibility for making the heavier isotopes of Md or Lr for study by bombarding Bk or Es targets with /sup 18/O.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5468377
• Report Number(s): LA-UR-80-1259; CONF-800362-1; TRN: 80-009147
• Resource Relation: Conference: 25. anniversary of the discovery of mendelevium meeting, Berkeley, CA, USA, 28 Mar 1980
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
MENDELEVIUM
NUCLEAR PROPERTIES
CALIFORNIUM 256
DAUGHTER PRODUCTS
DECAY
FERMIUM 258
FERMIUM 259
MENDELEVIUM 259
STABILITY
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ACTINIDES
CALIFORNIUM ISOTOPES
ELEMENTS
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FERMIUM ISOTOPES
HEAVY NUCLEI
ISOTOPES
MENDELEVIUM ISOTOPES
METALS
MICROSEC LIVING RADIOISOTOPES
NUCLEI
ODD-EVEN NUCLEI
RADIOISOTOPES
TRANSPLUTONIUM ELEMENTS
TRANSURANIUM ELEMENTS
652022* - Nuclear Properties & Reactions
A=220 & above
Experimental- Radioactive Decay- (-1987)