Measurements of Seeing-Induced Crosstalk in Tip-Tilt Corrected Solar Polarimetry

We present measurements of seeing-induced crosstalk using spectropolarimetric observations of sunspots recorded simultaneously in the H alpha and Ca II 8662 & Aring; lines with the Kodaikanal Tower Tunnel (KTT) telescope. The Kodaikanal Tower Tunnel telescope is integrated and installed with an image stabilization system consisting of a tip-tilt and an autoguider system. Additionally, the spectropolarimeter at KTT is upgraded to allow for the simultaneous recording of spectropolarimetric observations in three spectral lines. The tip-tilt system is shown to have a cutoff frequency of 80 Hz, effectively reducing the seeing induced crosstalk in the measured Stokes parameters by at least a factor of 2. (c) 2024 Optica Publishing Group