COMPENSATION OF SELF-HEATING IN THE MEASUREMENT OF THE DYNAMIC-RESPONSE OF A THERMORESISTIVE SENSOR

In the experimental determination of the response time of a thermoresi stive sensor to a radiation step, one needs to monitor the variation o f the ohmic resistance of the sensor with time. This requires passing electrical current through the sensor, which introduces error in the m easured response time due to the additional self-heating of the sensor by the electrical current. A theoretical,method to eliminate this err or is formulated and experimental results are presented. The proposed method also permits experimental determination of the heat capacity (m e) and hear transfer coefficient (UA). The sensitivity analysis of tau = mc/UA permits the optimal choice for the resistance measurement cur rents.