Abstract

The Solar Ultraviolet Measurements of Emitted Radiation (SUMER) instrument on the Solar and Heliospheric Observatory (SOHO) satellite is sensitive to the state of linear polarization of the incident radiation primarily owing to two optical elements, the holographic grating and the wavelength scan mirror. The large angle of incidence of light striking the scan mirror, which varies from roughly 73.3° to 81.6° (with respect to the mirror normal), causes the mirror to act as a linear polarizer. Similarly, the spectrometer grating operates at incidence angles between 16.7° and 35.0°, adding to the polarization effect at some wavelengths. Measurement and characterization of this polarization sensitivity as a function of wavelength were performed with the engineering model optics (scan mirror and grating) and synchrotron radiation, which is nearly 100% linearly polarized, from the Super Anneau de Collisions d’Orsay (SUPERACO) positron storage ring in Orsay3. The polarization sensitivity or modulation factor of the SUMER instrument was found to be between 0.4 and 0.6, depending on the wavelength and the angle of incidence of light striking the scan mirror; this agrees with the calculated polarization properties based on the measured optical constants for the silicon carbide mirror and grating.

© 1997 Optical Society of America

Radiometric calibration of SUMER: refinement of the laboratory results under operational conditions on SOHO

Klaus Wilhelm, Philippe Lemaire, Uri Feldman, Jörg Hollandt, Udo Schühle, and Werner Curdt
Appl. Opt. 36(25) 6416-6422 (1997)

Radiometric calibration of the telescope and ultraviolet spectrometer SUMER on SOHO

Jörg Hollandt, Udo Schühle, Wolfgang Paustian, Werner Curdt, Michael Kühne, Burkhard Wende, and Klaus Wilhelm
Appl. Opt. 35(25) 5125-5133 (1996)

Intercalibration of SUMER and CDS on SOHO. II. SUMER detectors A and B and CDS NIS

Anuschka Pauluhn, Isabelle Rüedi, Sami K. Solanki, Udo Schühle, Klaus Wilhelm, Jim Lang, William T. Thompson, and Jörg Hollandt
Appl. Opt. 40(34) 6292-6300 (2001)

Intercalibration of SUMER and CDS on SOHO. I. SUMER detector A and CDS NIS

Anuschka Pauluhn, Isabelle Rüedi, Sami K. Solanki, Jim Lang, C. Dave Pike, Udo Schühle, William T. Thompson, Jörg Hollandt, and Martin C. E. Huber
Appl. Opt. 38(34) 7035-7046 (1999)

Intercalibration of SUMER and CDS on SOHO. III. SUMER and CDS-GIS

Anuschka Pauluhn, Jim Lang, Eddie R. Breeveld, Sami K. Solanki, and Udo Schühle
Appl. Opt. 42(4) 657-666 (2003)