Development of a secondary triton beam from primary 16,18O beams for (t,3He) experiments at intermediate energies

The in-flight heavy-ion fragmentation technique has been used to produce a secondary beam of tritons (3H) at intermediate energies (Et > 100 MeV / nucleon) from primary 16,18O beams of 150 and 120 MeV/nucleon, respectively. The best results are obtained with a 16O beam of 150 MeV/nucleon, producing a 115 MeV/nucleon triton beam. The triton beam will be used in (t,3He) charge-exchange experiments at the S800 spectrometer at the NSCL. At the target of the S800, a triton rate of 5 × 106 particles per second is achieved, for a primary 16O beam of 100 pnA. The (t,3He) reaction using this beam was tested with a 24Mg target. An excitation-energy resolution of 190 ± 15 keV is achieved

Gamow-Teller strengths in 24 Na using the 24 Mg( t , 3 He) reaction at 115 A MeV

Gamow-Teller transitions from Mg24 to Na24 were studied via the (t,3He) reaction at 115A MeV using a secondary triton beam produced via fast fragmentation of 150A MeV O16 ions. Compared to previous (t,3He) experiments at this energy that employed a primary α beam, the secondary beam intensity is improved by about a factor of five. Despite the large emittance of the secondary beam, an excitation-energy resolution of ∼200 keV is achieved. A good correspondence is found between the extracted Gamow-Teller strength distribution and those available from other charge-exchange probes. Theoretical calculations using the newly developed USDA and USDB sd-shell model interactions reproduce the data well