β-delayed Multi-particle Emission From 31^Ar

The β^+ decay of ^(31)Ar was investigated in an experiment at the GSI-FRS spectrometer.The ions of interest have been produced in the fragmentation of a ^(36)Ar beam at 880 Me V/nucleon and implanted in a time projection chamber with optical readout. In addition to β-delayed one and two proton emission, for the first time the emission of β-delayed 3 protons has been observed. The branching ratio for this decay mode is found to be(0.07 ± 0.02)%.

Revisit to Two-Proton Radioactivity of 19Mg and Observation of Two-Proton Decay of 30Ar

An experiment aimed to investigate the two-proton(2p) decay of the previously unknown nucleus ^(30)Ar was performed at GSI. By tracking the decay products in-flight with silicon micro-strip detectors, the 2p decays of ^(30)Ar were observed for the first time. For the calibration purpose, 2p decays of ^(19)Mg were also remeasured by tracking the coincident ^(17)Ne+p+p trajectories. By comparing the measured angular p-17 Ne correlations with those obtained from the corresponding Monte Carlo simulations,the simultaneous 2p decay of ^(19)Mg ground state and the sequential 2p emission of several known excited states of ^(19)Mg were confirmed. One new excited state in ^(19)Mg and two new excited states in ^(18)Na were observed.

Influence of breakup on elastic and α-production channels in the ^6Li＋^116Sn reaction

The effects of breakup reactions on elastic and α-production channels for the ^6Li＋^116Sn system have been investigated at energies below and near the Coulomb barrier. The angular distributions of α-particle production differential cross sections have been obtained at several projectile energies between 22 and 40 MeV. The measured breakup α-particle differential cross sections and elastic scattering angular distributions have been compared with the predictions of continuum-discretized coupled channels（CDCC） calculations. The influence of breakup coupling has also been investigated by extracting dynamic polarization potentials（DPP） from the CDCC calculations. From the predictions of CDCC calculations the relative importance of the nuclear, Coulomb, and total breakup contributions have also been investigated. The nuclear breakup couplings are observed to play an important role in comparison to the Coulomb breakup for the direct breakup mechanisms associated in the reaction of ~6Li projectile with ^（116）Sn target nuclei. The influence of strong nuclear breakup coupling exhibits suppression in the Coulomb-nuclear interference peak. The direct breakup cross sections from the CDCC calculations under-predict the measured α-particle differential cross sections at all energies. This suggests that the measured α particles may also have contributions from other possible breakup reaction channels.