Angular correlation measurement of gamma ray transitions in the decay of 207Bi

Gamma-gamma directional correlation measurements have been carried out for the gamma cascades in 207Pb using fast-slow coincidence system, at gamma energies (1063.62-569.67)keV and (1770.22-569.67)keV. Correlation data for the two cascades were analysed for A2 and A4 coefficients. Evidence is shown for the existance of nuclear perturbation. Mixing ratio and the reduced transition probability for the 1770.22 keV transition have been calculated after allowing for the extra nuclear perturbation of the (1770.22-569.67)keV cascade. (author)