Two-neutron excitations in 26Mg and 30Si
Abstract
The reactions 24Mg(t, p)26Mg and 28Si(t, p)30Si have been studied at an incident energy of 18 MeV. Angular distributions have been measured for strongly excited states up to an excitation energy of about 10.5 MeV. A comparison with DWBA calculations using transition amplitudes resulting from a full (sd) shell model calculation generally shows good agreement up to an excitation energy of about 6 MeV, although a few states show significant discrepancies. At higher excitation energies the natural-parity states of the multiplet, and the 2+ and 4+ states of the configuration can be identified in both 30Si and 26Mg. The 6+ state is identified in 30Si, but not in 26Mg. The expected 0+ states are not clearly identified in either case, although relatively strong transitions with “uncharacteristic” angular distributions are observed near the expected location of these states. DWBA calculations with a form factor suggest that these may in fact be the 0+ states of the configuration.
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- •
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- •
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- •
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- •
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