Height variation of the vector magnetic field in solar spicules

TL;DR

This study uses spectropolarimetric data to analyze the height-dependent magnetic field in solar spicules, revealing a rapid decrease in magnetic strength and changes in field inclination with altitude.

Contribution

First detailed spectropolarimetric measurements of solar spicule magnetic fields with height variation analysis using the HAZEL inversion code.

Findings

Magnetic field strength decreases from 80 G at the base to 30 G at 3000 km height.

Magnetic field is nearly vertical at the chromosphere base and inclines to about 50 degrees above 2 Mm.

Provides new insights into the magnetic configuration of solar spicules.

Abstract

Proving the magnetic configuration of solar spicules has hitherto been difficult due to the lack of spatial resolution and image stability during off-limb ground-based observations. We report spectropolarimetric observations of spicules taken in the He I 1083 nm spectral region with the Tenerife Infrared Polarimeter II at the German Vacuum Tower Telescope of the Observatorio del Teide (Tenerife; Canary Islands; Spain). The data provide the variation with geometrical height of the Stokes I, Q, U, and V profiles whose encoded information allows the determination of the magnetic field vector by means of the HAZEL inversion code. The inferred results show that the average magnetic field strength at the base of solar spicules is about 80 gauss and then it decreases rapidly with height to about 30 gauss at a height of 3000 km above the visible solar surface. Moreover, the magnetic field vector is close to vertical at the base of the chromosphere and has mid inclinations (about 50 degree) above 2 Mm height.