Some comments on the matching of photometric and magnetic properties of structures at the solar surface

TL;DR

This paper examines the relationship between magnetic and photometric features of solar surface structures, revealing that magnetic boundaries often do not align with visible features and that strong magnetic fields can exist without visible sunspots.

Contribution

It challenges the traditional view of magnetic tubes with clear boundaries and provides new insights into magnetic field presence during sunspot absence.

Findings

Magnetic boundaries do not always match photometric boundaries.

Strong magnetic fields (>800 Gauss) can exist without visible sunspots.

Magnetic fields may originate from depths beneath the photosphere.

Abstract

We investigate sharply outlined features recorded in solar magnetic field tracers. It is shown that the magnetic boundaries of a sunspot do not coincide with the photometric ones. Moreover, there is no clear magnetic boundary around sunspots. Thus, the widely accepted concept of a magnetic tube with clearly pronounced borders is not always correct and should be used with caution. It is also shown that even in the periods of complete absence of visible spots on the Sun, there are magnetic fields over 800 Gauss. The nature of these strong magnetic fields remains unclear; they may originate at relatively small depths under the photosphere.