The properties of horizontal magnetic elements in quiet solar intranetwork

Abstract

Using the data observed by the Solar Optical Telescope/Spectro-Polarimeter aboard the Hinode satellite, the horizontal and vertical fields are derived from the wavelength-integrated measures of Zeeman-induced linear and circular polarizations. The quiet intranetwork regions are pervaded by horizontal magnetic elements. We categorize the horizontal intranetwork magnetic elements into two types: one is the non-isolated element which is accompanied by the vertical magnetic elements during its evolution; another is the isolated element which is not accompanied by the vertical magnetic elements. We identify 446 horizontal intranetwork magnetic elements, among them 87 elements are isolated and 359 are non-isolated. Quantitative measurements reveal that the isolated elements have relatively weaker horizontal magnetic fields, almost equal size, and shorter lifetime comparing with the non-isolated elements. Most non-isolated horizontal intranetwork magnetic elements are identified to associate with the emergence of Omega-shaped flux loops. A few non-isolated elements seem to indicate scenarios of submergence of Omega loops or emergence of U-like loops. There is a positive correlation between the lifetime and the size for both the isolated and non-isolated HIFs. It is also found that there is also positive correlation between the lifetime and the magnetic flux density for non-isolated HIFs, but no correlation for isolated HIFs. Even though the horizontal elements show lower magnetic flux density, they could carry the total magnetic flux in the order of magnitude close to 10^25 Mx to the solar surface each day.