Measurement of In-Band Transition Probabilities at High Spin

Quantitative measurements have been made of correlations in the $\gamma$-ray continuum emitted by rotational nuclei populated in heavy-ion compound-nucleus reactions. The experimentally deduced intensity of the "ridge" structure in the correlation spectrum implies an average probability for inband stretched $E2\mathrm{}$ decay of < 20% at spins above $30\hslash$ in contrast to traditional expectations.