The structure of28Si above 10 MeV excitation energy I: gamma-decay modes and radiative widths of levels

The systematics of-decay modes and radiative widths of highly excited states in²⁸Si has been extended by taking-ray spectra on 60 resonances of the²⁷Al(p,) reaction in the range 1097 keVE_p 4492 keV (12643 keVE_x 15915 keV) and on the²⁴Mg(,) resonances atE=3355, 3431, 4003 keV (E_x=12860, 12925, 13 415 keV). The-decay modes of levels in the sub-resonance region (E_x=10–12.5 MeV) were studied with both the²⁷A1(p, ) reaction and the²⁷A1(d, n) reaction at E_d=4,5,6 MeV. Information on radiative widths of levels was obtained by measuring the resonance strengthsS=(2I+1)_p/ for 52 resonances of the²⁷Al(p, ) reaction with an emphasis on prospective T=1 states.