20 July 2010 Correcting polarization crosstalk in the ESPaDOnS spectro-polarimeter
Author Affiliations +
Abstract
ESPaDOnS is a high-resolution, cross-dispersed, fiber fed, echelle spectrograph in use at the Canada-France-Hawaii Telescope (CFHT). The light from the telescope passes through a polarimeter stage before being injected into the fibers that feed the spectrograph, so the instrument is capable of determining the polarization of the stellar spectra from 370 - 1000 nm in wavelength. One limit to the accuracy of the polarimetry is the inevitable polarization crosstalk added by all optics prior to polarization analysis. The main source of this crosstalk is stress birefringence in the glass of the optics; either residual from the annealing process or induced by the mounting of the optics. The process by which the crosstalk in ESPaDOnS has been reduced from 5% or more to less than 1% is discussed in this paper.
© (2010) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Gregory Barrick, Tom Benedict, Dan Sabin, "Correcting polarization crosstalk in the ESPaDOnS spectro-polarimeter", Proc. SPIE 7735, Ground-based and Airborne Instrumentation for Astronomy III, 77354C (20 July 2010); doi: 10.1117/12.856084; https://doi.org/10.1117/12.856084
PROCEEDINGS
12 PAGES


SHARE
Back to Top