Metrological Characterization of a High-Temperature Hybrid Sensor Using Thermal Radiation and Calibrated Sapphire Fiber Bragg Grating for Process Monitoring in Harsh Environments oleh René Eisermann, Stephan Krenek, Tobias Habisreuther, Petra Ederer, Sigurd Simonsen, Helge Mathisen, Tino Elsmann, Frank Edler, Daniel Schmid, Adrian Lorenz, Åge Andreas Falnes Olsen