Polar cap magnetic field reversals during solar grand minima: could pores play a role?

Author： Švanda Michal Brun Allan Sacha Roudier Thierry Jouve Laurène

E-ISSN： 1432-0746|586|issue|A123-A123

ISSN： 0004-6361

Source： Astronomy & Astrophysics, Vol.586, Iss.issue, 2016-02, pp. : A123-A123

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

We study the magnetic flux carried by pores located outside active regions with sunspots and investigate their possible contribution to the reversal of the global magnetic field of the Sun. We find that they contain a total flux of comparable amplitude to the total magnetic flux contained in polar caps. The pores located at distances of 40–100 Mm from the closest active region systematically have the correct polarity of the magnetic field to contribute to the polar cap reversal. These pores can be found predominantly in bipolar magnetic regions. We propose that during grand minima of solar activity, such a systematic polarity trend, which is akin to a weak magnetic (Babcock-Leighton-like) source term, could still be operating but was missed by the contemporary observers because of the limited resolving power of their telescopes.