The standard Si microstrip detector samples were irradiated to high fluence in TRIGA reactor.
The magnetoresistance was investigated at different temperature, and the preliminary results of mobility dependence was obtained. It was found a decrease of magnetoresistance mobility up to 640 cm2/sV @ room T in samples irradiated to 1e17 neutron/cm2 fluence. The mobility was near to the same in both FZ and MCZ Si samples but at the lower fluence the differences between the Si type was bigger. The details of the measurement technique and results needs to discuss.