The coronograph-polarimeter: An algorithm for creation of solar corona polarization images

Abstract

An algorithm for polarization imaging of the white light corona has been devised on the basis of the Stokes vector presentation and the IDL software applied to statistical data. The use of the algorithm for a 24-frame color negative polarization film of the corona of November 3, 1994, digitized in the “green” light allowed new data to be obtained on the distribution of the polarization degree in the “white” (summary of the blue and red spectral interval emissions) corona. On the average, the monotonic increase in the polarization degree, which is characteristic for the van de Hülst model, was not found over the range (1.2–2.0)R _⊙ in heliolatitudes ±45°.The polarization degree was virtually constant in the region (1.2–1.4)R _⊙.The apparent “plateau” in the polarization degree distribution is obviously due to the deviation of the model with local spherical symmetry from the actual 3D structure of the inner corona.