SummaryThe 90° yields of y·rays from the reaction 27Al(p,y)28Si have been obtained at intervals of 40 ke V for proton energies between 8·02 and 10·42 MeV. The ground state y-ray (Yo) and the first excited state y-ray (Yl) were adequately resolved. The two yield curves show considerable structure and, with the present resolution, there is a strong one-way correspondence between them. The gross structure of the Yo yield curve is compared with data from the 28Si( y,n)27Si reaction and fair agreement is found.