Gamma sensor having combined thermal bridge and centering means

摘要

A gamma sensor is supported coaxially in a bore, extending through the core of a nuclear reactor, by centering means which span the annular space between the gamma sensor and the bore. Said centering means also acts as a thermal bridge so that the portion of the gamma sensor contacted by the centering means will assume a thermal temperature close to that of the bore. Since poor thermal contact between the gamma sensor and the bore is thereby avoided, the accuracy of sensor readings is improved.