Microscopic structure of the Gamow-Teller resonance in Cu-58

The 2osPb(3He,t)20sBi reaction has been studied with the RCNP ring cyclotron at E(3He) = 450 MeV using the magnetic spectrometer Grand Raiden at 0 = 0”. The Gamow-Teller resonance is strongly excited at this bombarding energy. Its microscopic structure has been investigated by measuring the direct proton decay to the neutron-hole states in ‘07Pb. The branching ratio for proton emission of a few % is much smaller than that for the decay of the isobaric analog state. The total width of the Gamow-Teller resonance as well as its total and partial escape widths have been determined. Several recent theoretical estimates for the escape width differ from the measured values by factors of - 2.5.

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