Measurement of helium temperatures by TVO-sensors under magnetic fields

Characteristics of Cryogenic Temperature Sensors Under Magnetic Fields

“…For example, can be described by the equation (4) whose coefficients depending only on B-value are as follows. for the range up to 9 T and from 1.52 to 4.43 K, and for the range up to 6 T and from 4.43 to 5.0 K. As it is shown in [8], the deviations of the majority of the experimental -points-92%-calculated by means of (4) are within the value of 20 mK for the temperature range from 1.52 to 4.43 K.…”

“…It is admitted to warm the sensor to 425 K without changing its calibration [7]. This sensor can be recommended for routine measurements in the high magnetic field [8] and radiation environment [9], [10].…”

“…The values of relative magneto-resistance and for the batch of 20 TVO sensors can be found in [8]. For example, can be described by the equation (4) whose coefficients depending only on B-value are as follows.…”

“…However, the way to determine -values for RIRT with the accuracy of 0.01 K can be derived. Processing the experimental data for this sensor has shown that if the calibration dependence for RIRT is known for the case of , the values can be calculated with the accuracy of 0.01 K for the ranges from 3 to 80 K and 0 to 7 T using (8) (8) where , and depend only on the temperature. Influence of the orientation of the RIRT thermometers in the magnetic field can be taken into account by the Q-factor which is the ratio between the values of at perpendicular and parallel orientations of the sensor with respect to the magnetic filed (9) This is valid for the temperature range from 3 K to 20.4 K with the deviation of about 0.5%.…”

“…Relative temperature shift, 1T=T(0), due to the magnetic field, B, versus temperature, T, for RIRT.For the temperature range from 4.43 to 5.0 K and B-values up to 6 T, one can use[8] …”