Transcript Known Proton Emitters
Proton emission from deformed rare earth nuclei
Robert Page
Simple model for spherical proton emitters
Proton decay of 160 Re
Q p E proton A A 1 S p
Q p = 1271 keV
t 1 / 2 e AREA
Proton emission as a spectroscopic tool
h 11/2
160 Re Half-life (ms) E p (keV) 1263
d 3/2
0.24
h 11/2
Expt 480 0.67
d 3/2
S t 1 / 2 ( calc ) t 1 / 2 ( expt )
Deformed proton emitters 135 Tb P.J. Woods et al., PRC69 (2004) 051302
Known Proton Emitters B. Blank & M.J.G. Borge, Progress in Particle and Nuclear Physics 60 (2008) 403
Known Proton Emitters Why are there so few known proton emitters in this region?
Selectivity Yield B. Blank & M.J.G. Borge, Progress in Particle and Nuclear Physics 60 (2008) 403
Implantation – proton – alpha correlation
Decay Particle Energy (MeV)
The proton emitter 159 Re t 1/2 = 21 m s
Decay Particle Energy (MeV)
D.T. Joss et al., Physics Letters B641 (2006) 34
Implantation – proton correlations 50 Cr + 92 Mo → 135 Tb + p6n Argonne FMA A = 135 only 60 m m thick DSSD P.J. Woods et al., PRC69 (2004) 051302
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 p
x
n reactions ~ 3 nb ~ 30 m b
(Super-)FRS A & Z separation AIDA Isomer g decays or known p for unique A & Z identification Selectivity
Predicted Super FRS Yields @ 10 12 /s Yield Neutron number N = 3.6 / hour = 0.6 / week
Predicted Super FRS Yields @ 10 12 /s Yield = 3.6 / hour = 0.6 / week Neutron number N
Some physics opportunities
• • • • •
New proton emitters Weak proton-decay branches Proton-decay fine structure Precision measurements Beta-delayed gamma spectroscopy
Outstanding questions
• • •
Background from
b
and
b
p decays (1 mm thick DSSDs cf. 60
m
m) Identify best physics cases Choose best primary beam Your input is welcome...