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

0461427 - ASÚ 2017 RIV FR eng J - Journal Article
Švanda, Michal - Brun, A.S. - Roudier, T. - Jouve, L.
Polar cap magnetic field reversals during solar grand minima: could pores play a role?
Astronomy & Astrophysics. Roč. 586, February (2016), A123/1-A123/11. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA ČR(CZ) GA14-04338S
Institutional support: RVO:67985815
Keywords : dynamo * Sun * magnetic fields
OECD category: Astronomy (including astrophysics,space science)
Impact factor: 5.014, year: 2016

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.
Permanent Link: http://hdl.handle.net/11104/0261021