Channel cross correlation and intermediate resonance in the /sup 55/Mn(p,p)/sup 55/Mn and /sup 55/Mn(p,. cap alpha. )/sup 52/Cr reactions

The excitation functions for the ..cap alpha.. particles and protons from the reactions /sup 55/Mn(p,p)/sup 55/Mn and /sup 55/Mn(p,..cap alpha..)/sup 52/Cr were measured from E/sub p/ = 5.8 to 7.0 MeV at theta/sub lab/ = 90/sup 0/, 125/sup 0/, and 160/sup 0/. The cross sections were analyzed by the channel cross correlation function, the autocorrelation function, and the statistical compound nuclear theory of Feshbach to determine the number of correlating channels n/sub d/, the average total level width , and the ratio /D. With these values, the theoretical intermediate width was calculated to be 27 +- 11.7 keV, which was consistent with the experimental result 36 +- 8 keV within the errors. The ratio n/sub d/(n/sub d/-1)/n/sup 2/ was determined to be 0.63 +- 0.16, which was also in agreement with the theoretical prediction (2D/..pi../sup 1/2/ = 0.40 +- 0.0 9, within the error.