Telescope system unwanted polarization and its mitigation
Abstract
To understand several important astrophysical processes requires that we measure the vector-wave (polarization) nature of the radiation incident on a telescope/instrument system. A few examples are: magnetic fields in stars and galaxies, dust haloes around stars, proto-planetary formation, solid bodies that reveal themselves through scattered light and stellar coronal activity. Optical and Ultra-violet components in telescopes and instruments contribute their own partial polarization to the radiation as it proceeds through the system to the detector and mask the astrophysical phenomena. A singular example is the polarization properties of the Terrestrial Planet Finder (TPF) coronagraph. The measurement of the polarization in an astronomical source is often obscured by the internal telescope/instrument polarization to mask important astrophysical phenomena. Astronomical telescopes and instruments have polarization dependent transmissivity. Polarization preserving optics is needed for optical and infrared astronomy from the ground (OIR) and electromagnetic observations from space (EOS). This white paper describes a technology development in metrology, modeling, materials science, micro and nano-structure development of mirror materials to mitigate many of the deleterious effects of telescope/instrument polarization through research and development of highly reflecting optical-UV thin film coating systems for ground and space telescopes and instruments. There is little or no commercial interest for these high-performance films and therefore NASA, the prime user of this technology needs to support this technology.
- Publication:
-
astro2010: The Astronomy and Astrophysics Decadal Survey
- Pub Date:
- March 2009
- Bibcode:
- 2009astro2010T..55B