The Spectro-Polarimeter (SP) of the Andrei B. Severny Solar Tower Telescope (STT) at the Crimean Astrophysical Observatory: Optical Design and Implementation

TL;DR

The paper introduces the optical design and initial results of the Spectro-Polarimeter installed at the Crimean Astrophysical Observatory, enabling detailed spectropolarimetric solar observations for magnetic and thermodynamic studies.

Contribution

It presents the design, implementation, and commissioning results of a new high-resolution spectropolarimeter for solar observations at the Crimean Observatory.

Findings

Achieved spectral resolution of 70,000.

Enabled simultaneous observations in three spectral ranges.

Successfully commissioned the instrument for solar magnetic studies.

Abstract

The Spectro-Polarimeter (SP) is a new instrument installed at the upgraded Andrei B. Severny Solar Tower Telescope (STT) at the Crimean Astrophysical Observatory. The instrument is a traditional echelle slit dual-beam spectropolarimeter with temporal modulation of the polarization. STT-SP provides simultaneous spectropolarimetric observations of the Sun within three 15 Angstrom wide spectral ranges around photospheric Fe I 5250, Fe I 5324, and chromospheric Mg I b2 5172 spectral lines. The spectral resolution of the instrument reaches 70,000 with the seeing-constrained slit width of 1 arcsec. The field-of-view of STT-SP is 200 arcsec allowing one to map a moderate size active region within a single raster scan. The instrument will provide new opportunities in the analysis of magnetic fields and thermodynamics of the lower atmosphere of the Sun. In this paper we describe the optical design of STT-SP and present the preliminary results acquired during the commissioning of the instrument.