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 Two fission groups: 1)From 257 Rf: 2)From 256 Rf: SF branch ratio of 257 Rf: Somerville et al., PRC 31, 1801 (1985): 0.14(9) Mass of α- correlated ERs Mass of SF- correlated ERs random

4. (High-K) Isomers in 257 Rf ER Daughter Isomeric γ or ICE Alpha E (keV) lnT(implant-ICE) Electron E (keV) B B A A α Ground Isomeric Ground/Isomeric Electron E vs.lnT Electron-alpha correlation 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: 58 Fe @ 264 MeV on 208 Pb → 265 Hs + 1n From: S. Hofmann, Rep. Prog. Phys. 61 (1998) 639 Production cross section: 63±10 pb 5 known alpha lines 1 known isomeric state

6. Wish List Intensity, intensity, intensity Long experiments Complicated setup → campaigns Dedicated detection system → complete spectroscopy