proton emission from deformed rare earth nuclei robert page
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Proton emission from deformed rare earth nuclei
Robert Page
Simple model for spherical proton emitters
pprotonp S1A
AEQ
Proton decay of 160Re
Qp = 1271 keV
AREA2/1 et
160Re Half-life (ms)
Ep (keV) d3/2 h11/2 Expt
1263 0.24 480 0.67
h11/2
d3/2)(t
)calc(tS
2/1
2/1
expt
Proton emission as a spectroscopic tool
Deformed proton emitters
P.J. Woods et al., PRC69 (2004) 051302
135Tb
Known Proton Emitters
B. Blank & M.J.G. Borge, Progress in Particle and Nuclear Physics 60 (2008) 403
Known Proton Emitters
B. Blank & M.J.G. Borge, Progress in Particle and Nuclear Physics 60 (2008) 403
SelectivityYield
Why are there so few knownproton emitters in this region?
Implantation – proton – alpha correlation
Decay Particle Energy (MeV)
Coun
ts (
106 )
/ 10
keV
Coun
ts /
10
keV
Decay Particle Energy (MeV)
t1/2 = 21 s
The proton emitter 159Re
D.T. Joss et al., Physics Letters B641 (2006) 34
Implantation – proton correlations
P.J. Woods et al., PRC69 (2004) 051302
50Cr + 92Mo → 135Tb + p6n
Argonne FMA
A = 135 only
60 m thick DSSD
Beta-decay half-lives
Moller, Nix & Kratz, Atomic Data & Nuclear Data Tables 66 (1997) 131
Proton-decay half-lives
Fusion-evaporation reactions
Compound nuclei
Fusion-evaporation pxn reactions
30 b
3 nb
(Super-)FRS A & Z separation
Isomer decays or known pfor unique A & Z identification
AIDA
Selectivity
Predicted Super FRS Yields @ 1012/s
Neutron number N
Atom
ic n
umbe
r Z
= 3.6 / hour= 0.6 / week
Yield
Predicted Super FRS Yields @ 1012/s
Neutron number N
Atom
ic n
umbe
r Z
= 3.6 / hour= 0.6 / week
Yield
Some physics opportunities
• New proton emitters• Weak proton-decay branches• Proton-decay fine structure• Precision measurements• Beta-delayed gamma spectroscopy
Outstanding questions
• Background from and p decays(1 mm thick DSSDs cf. 60 m)
• Identify best physics cases• Choose best primary beam
Your input is welcome...
Robert Page