Classical activation method is often used in the reactor physical experiment forrelative measurements of neutron flux distribution in a reactor

this method takes much time and can not get the results quickly. By using a kind of micro-neutron detector with conventional electronic equipment and mechanical device

we measured the axis relative distribution of neutron flux on-line in the light water zero-power reactor. The deviation of the results obtained by using microdetector on-line from off-line is less than 3%.