Structure%20of%20Super-Heavy%20Elements

1
Structure of Super-Heavy Elements

• Andreas Heinz
• A. W. Wright Nuclear Structure Laboratory
• Yale University
• ATLAS Workshop, August 8-9, 2009

2
Motivation

• Understanding the evolution of nuclear structure
  of the heaviest nuclei.
• The FMA measures A/q - an additional parameter
  which is very useful for the interpretation of
  complicated decay spectra and the measurement of
  weak branching ratios.
• Spectroscopy at the limits decay of isomeric
  states provides valuable information on nuclear
  structure.

3
Measuring Weak Branching Ratios
random
Mass of a-correlated ERs

• Two fission groups
• From 257Rf
• From 256Rf

Mass of SF-correlated ERs
SF branch ratio of 257Rf Somerville et al., PRC
31, 1801 (1985) 0.14(9)
4
(High-K) Isomers in 257Rf
Isomeric
Electron E vs.lnT
Isomeric
? or ICE
Ground/Isomeric
ER
Electron-alpha correlation
a
Ground
Daughter
Decay of high-K isomers can provide valuable
information of non-collective states near the
Fermi energy. High-K isomers might become more
stable than the ground state.
J. Qian et al., PRC 79, 064319 (2009)
5
Possible Future Experiment 58Fe _at_ 264 MeV on
208Pb ? 265Hs 1n
Production cross section 6310 pb 5 known alpha
lines 1 known isomeric state
From S. Hofmann, Rep. Prog. Phys. 61 (1998) 639
6
Wish List

• Intensity, intensity, intensity
• Long experiments
• Complicated setup ? campaigns
• Dedicated detection system ? complete spectroscopy