Properties of G-band Bright Points derived from IBIS observations

TL;DR

This study analyzes the properties of photospheric Bright Points in different solar regions using IBIS observations, revealing their magnetic nature, surface coverage, and dynamic behavior relevant to coronal heating.

Contribution

It provides new insights into the magnetic and dynamic properties of Bright Points in active and quiet Sun regions based on high-resolution spectroscopic and spectro-polarimetric data.

Findings

BPs cover up to 3% of the solar surface outside active regions.

BPs are composed of magnetic flux element aggregations.

Horizontal velocities of BPs reach up to 2 km/s.

Abstract

We have investigated properties of photospheric Bright Points (BPs) observed in an Active Region during its decay phase and in a quiet Sun region. We have analyzed two sets of photospheric observations taken with IBIS (Interferometric Bidimensioal Spectrometer) at the NSO Dunn Solar Telescope. The first set consists of spectral data acquired in the Fe I 709.0 nm and Ca I 854.2 nm lines and simultaneous broad-band and of G-band observations. The second set consists of spectro-polarimetric observations in the Fe I 630.15 nm - 630.25 nm doublet and simultaneous white light and G-band observations. The relation between BP filling factor and RMS image contrast indicates that, on average, BPs cover up to 3% of the solar surface outside Active Regions. The relation between area and intensity values of the features identified on both data sets suggests that they are composed of aggregations of magnetic flux elements. The horizontal velocity values are as high as 2 km/s, thus supporting the scenario of BPs motion contributing to the coronal heating.