Photonic thermometer module assembly and performing photonic thermometry

A photonic thermometer module assembly for performing photonic thermometry, the photonic thermometer module assembly comprising:

• a sheath comprising an inner volume, a first end, and a second end disposed at an opposite end of the sheath than the first end;
• a sheath bottom plug disposed on the sheath at the second end such that the sheath bottom plug hermetically seals the sheath at the second end;
• a top inner-wall-mount flange disposed at the first end;
• a top seal plug disposed on the top inner-wall-mount flange at the first end such that the top seal plug hermetically seals the sheath at the first end;
• a heat exchanger disposed on the sheath bottom plug such that the heat exchanger is in thermal communication with the sheath bottom plug;
• a photonic thermometer disposed on the heat exchanger such that the photonic thermometer is in thermal communication with the sheath bottom plug through the heat exchanger, the heat exchanger is interposed between the photonic thermometer and the sheath bottom plug, and the photonic thermometer determines a temperature of the sheath;
• and
• an optical fiber array in optical communication with the photonic thermometer and that optically couples the photonic thermometer to an exterior environment of the photonic thermometer module assembly,
• wherein the photonic thermometer module assembly is compatible with International Temperature Scale of 1990 (ITS-90) fixed-point cell infrastructure and conventional drywell and oil-bath calibrations, and the photonic thermometer module assembly provides temperature measurements from −200° C. to +700° C.