Update of the Spectro-polarimeter on the Domeless Solar Telescope at Hida Observatory

Abstract

A new spectro-polarimeter was installed on the Domeless Solar Telescope at Hida Observatory. Major update s from the previous system are as follows; a super achromatic dual beam polarimeter, communication interface between telescope and data acquisition PC for image scanning , flexible setup for observing a wavelength range of 500-1100 nm, and a high sensitivity infrared camera. The field of view of the system is 120arcsec along the slit of spectrograph, and with a slit width of 0.64 arcsec, the system can achieve a sensitivity of 3x10⁻⁴ in a few second in on disk observation. Details of the instruments, the data reduction flow and initial results obtained by the new system are presented. At the end, future prospect is also discussed.