On the reduction and presentation of data in astronomical two-channel photopolarimetry
Abstract
Description
Many different methods exist for reducing data obtained when an astronomical source is studied with a two-channel polarimeter, such as a Wollaston prism system. This paper presents a rigorous method of reducing the data from raw aperture photometry, and evaluates errors both by a statistical treatment, and by propagating the measured sky noise from each frame. The reduction process performs a hypothesis test for the presence of linear polarization. The probability of there being a non-zero polarization is obtained, and the best method of obtaining the normalized Stokes Parameters is discussed. Point and interval estimates are obtained for the degree of linear polarization, which is subject to positive bias; and the polarization axis is found.
19 pages, 2 figures (both small). Uses modified Kluwer style files (included). Accepted for publication in Experimental Astronomy. PostScript version also available at ftp://ftp.astro.cf.ac.uk/pub/gjl/PolDataRedn.ps
19 pages, 2 figures (both small). Uses modified Kluwer style files (included). Accepted for publication in Experimental Astronomy. PostScript version also available at ftp://ftp.astro.cf.ac.uk/pub/gjl/PolDataRedn.ps