Structure of Structure of Super-Heavy ElementsSuper-Heavy Elements
Andreas HeinzAndreas HeinzA. W. Wright Nuclear Structure LaboratoryA. W. Wright Nuclear Structure Laboratory
Yale UniversityYale University
ATLAS Workshop, August 8-9, 2009ATLAS Workshop, August 8-9, 2009
MotivationMotivation
Understanding the evolution of nuclear Understanding the evolution of nuclear structure of the heaviest nuclei.structure of the heaviest nuclei.The FMA measures A/q - an additional The FMA measures A/q - an additional parameter which is very useful for the parameter which is very useful for the interpretation of complicated decay spectra interpretation of complicated decay spectra and the measurement of weak branching and the measurement of weak branching ratios.ratios.Spectroscopy at the limits: decay of isomeric Spectroscopy at the limits: decay of isomeric states provides valuable information on states provides valuable information on nuclear structure.nuclear structure.
Measuring Weak Branching Measuring Weak Branching RatiosRatios
Two fission groups:
1) From 257Rf:
2) From 256Rf:
sT 4.19.02/1 2.3
msT 96.130.12/1 89.4
SF branch ratio of 257Rf:
Somerville et al., PRC 31, 1801 (1985): 0.14(9)
Mass of Mass of αα--correlated ERscorrelated ERs
Mass of Mass of SF-SF-correlated ERscorrelated ERs
)1(02.0SFRfb
random
(High-K) Isomers in (High-K) Isomers in 257257RfRf
ER
Daughter
Isomeric
γ or ICE
Alpha E (keV)ln
T(im
plan
t-IC
E)
Electron E (keV)
B
B
A
A
α
sB
sA4.23.1
4231
1.4:
160:
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)
Possible Future Experiment: Possible Future Experiment: 5858Fe @ 264 MeV on Fe @ 264 MeV on 208208Pb Pb →→ 265265Hs + 1nHs + 1n
From: S. Hofmann, Rep. Prog. Phys. 61 (1998) 639
Production cross section: 63±10 pb
5 known alpha lines
1 known isomeric state
Wish ListWish List
Intensity, intensity, intensityIntensity, intensity, intensity
Long experimentsLong experiments
Complicated setup Complicated setup → campaigns→ campaigns
Dedicated detection system → Dedicated detection system →
complete spectroscopycomplete spectroscopy
Top Related