Proton emission from deformed rare earth nuclei Robert

Proton emission from deformed rare earth nuclei Robert Page

Simple model for spherical proton emitters Proton decay of 160 Re Qp = 1271 ke. V t 1 / 2 µ e AREA

Proton emission as a spectroscopic tool h 11/2 d 3/2 160 Re Half-life (ms) Ep (ke. V) d 3/2 h 11/2 Expt 1263 0. 24 480 0. 67

Deformed proton emitters 135 Tb P. J. Woods et al. , PRC 69 (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

Counts ( 106) / 10 ke. V Implantation – proton – alpha correlation Decay Particle Energy (Me. V)

Counts / 10 ke. V The proton emitter 159 Re t 1/2 = 21 ms Decay Particle Energy (Me. V) D. T. Joss et al. , Physics Letters B 641 (2006) 34

Implantation – proton correlations 50 Cr + 92 Mo → 135 Tb + p 6 n Argonne FMA A = 135 only 60 mm thick DSSD P. J. Woods et al. , PRC 69 (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 pxn reactions ~3 nb ~30 mb

(Super-)FRS A & Z separation AIDA Isomer g decays or known p for unique A & Z identification Selectivity

Atomic number Z Predicted Super FRS Yields @ 1012/s Yield Neutron number N = 3. 6 / hour = 0. 6 / week

Atomic number Z Predicted Super FRS Yields @ 1012/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 bp decays (1 mm thick DSSDs cf. 60 mm) • Identify best physics cases • Choose best primary beam Your input is welcome. . . Robert Page