T. F. Lang

A fast in-beam recoil catcher wheel and the observation of beta-delayed two-proton emission from 31Ar

Abstract A fast in-beam recoil catcher wheel has been constructed to perform particle spectroscopy on very proton-rich nuclei. The wheel speed can be varied to study nuclides whose half-lives range from 100 μs to ∼ 200 ms. Known beta-delayed proton emissions from the A = 4n + 1, T z = −3 2 nuclides 17 Ne, 21 Mg, and 25 Si as well as the beta-delayed two-proton decay from 22 Al( t 1 2 = 70 ms ) were measured to test the wheel. Subsequently, a beta-delayed two-proton branch from 31 Ar ( t 1 2 = 15 ms ) was observed.

Beta-delayed two-proton decay of39Ti

The beta-delayed two-proton decay of theTz=−5/2 nuclide39Ti has been observed. The39Sc isobaric analog state has been calculated to lie at 8.82 MeV using the measured two-proton sum energy of 4750±40 keV for its decay to the37K ground state. Combining this excitation energy with a Coulomb displacement energy calculation has lowered the energy available for ground state two-proton emission of39Ti from 760 to 530 keV.

Improvements to the helium-jet coupled on-line mass separator RAMA

Abstract Some general improvements to the on-line mass separator RAMA have yielded a factor of five increase in yield for most elements. By placing the ion-source region at the full accelerating potential of 20 kV, the effective skimmer-plasma distance has been reduced from 12 to

Beta‐delayed two‐proton emission as a nuclear probe

A brief history of beta‐delayed two‐proton emission is given. Speculations about future experiments which would enhance our knowledge about both nuclear spectroscopy and this relatively unique decay mode are presented.