Strategy for the inversion of Hinode spectropolarimetric measurements in the quiet Sun

TL;DR

This paper presents a new inversion strategy for analyzing Hinode spectropolarimetric data of the quiet Sun, accounting for local stray-light contamination to accurately determine magnetic field distributions.

Contribution

The paper introduces a novel inversion approach that considers local stray-light effects, improving the analysis of high-resolution Hinode spectropolarimetric measurements of the quiet Sun.

Findings

Quiet Sun internetwork regions mainly have hG magnetic fields.

Stray-light contamination is approximately 0.8 in these regions.

The method's robustness against noise and initial guesses was evaluated.

Abstract

In this paper we propose an inversion strategy for the analysis of spectropolarimetric measurements taken by {\em Hinode} in the quiet Sun. The spectropolarimeter of the Solar Optical Telescope aboard {\em Hinode} records the Stokes spectra of the \ion{Fe}{i} line pair at 630.2 nm with unprecendented angular resolution, high spectral resolution, and high sensitivity. We discuss the need to consider a {\em local} stray-light contamination to account for the effects of telescope diffraction. The strategy is applied to observations of a wide quiet Sun area at disk center. Using these data we examine the influence of noise and initial guess models in the inversion results. Our analysis yields the distributions of magnetic field strengths and stray-light factors. They show that quiet Sun internetwork regions consist mainly of hG fields with stray-light contaminations of about 0.8.