3 research outputs found
\b{eta}-delayed three-proton decay of 31Ar
The beta decay of 31Ar, produced by fragmentation of a 36Ar beam at 880
MeV/nucleon, was investigated. Identified ions of 31Ar were stopped in a
gaseous time projection chamber with optical readout allowing to record decay
events with emission of protons. In addition to \b{eta}-delayed emission of one
and two protons we have clearly observed the beta-delayed three-proton branch.
The branching ratio for this channel in 31Ar is found to be 0.07(2)%.Comment: 5 pages, 3 figures, submitted to Physical Rev.
Spectroscopy of excited states of unbound nuclei Ar and Cl
Several states of proton-unbound isotopes Ar and Cl were investigated by measuring their in-flight decay products, S+proton+proton and S+proton, respectively. A refined analysis of S-proton angular correlations indicates that the ground state of Ar is located at MeV above the two-proton emission threshold. The theoretical investigation of the Ar ground state decay demonstrates that its mechanism has the transition dynamics with a surprisingly strong sensitivity of the correlation patterns of the decay products to the two-proton decay energy of the Ar ground state and the one-proton decay energy as well as the one-proton decay width of the Cl ground state. The comparison of the experimental S-proton angular correlations with those resulting from Monte Carlo simulations of the detector response illustrates that other observed Ar excited states decay by sequential emission of protons via intermediate resonances in Cl. Based on the findings, the decay schemes of the observed states in Ar and Cl were constructed. For calibration purposes and for checking the performance of the experimental setup, decays of the previously-known states of a two-proton emitter Mg were remeasured. Evidences for one new excited state in Mg and two unknown states in Na were found