Measurements of total reaction cross section for light nuclei and evidence for the anomalous nuclear structure in C-15

Measurements of the total reaction cross section for C12-16, N14-17 and O16-18 on carbon target at intermediate energies were performed on RIBLL of HIRFL. A larger enhancement of sigma(n) for C-15 was observed than that for its neighbors. The analysis of these data indicates possible existence of an anomalous nuclear structure in C-15. A new quantity was suggested as the criterion to distinguish anomalous structure nuclei from normal nuclei.