1.
Appl Opt
; 63(15): 4088-4094, 2024 May 20.
Article
in English
| MEDLINE
| ID: mdl-38856502
ABSTRACT
We present measurements of seeing-induced crosstalk using spectropolarimetric observations of sunspots recorded simultaneously in the H α and Ca ii 8662 Å 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.