Magnetic properties on the boundary of an evolving pore

0547945 - ASÚ 2022 RIV FR eng J - Journal Article
García-Rivas, Marta - Jurčák, Jan - Bello González, N.
Magnetic properties on the boundary of an evolving pore.
Astronomy & Astrophysics. Roč. 649, May (2021), č. článku A129. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA ČR(CZ) GA18-06319S
Institutional support: RVO:67985815
Keywords : Sun * photosphere * magnetic fields
OECD category: Astronomy (including astrophysics,space science)
Impact factor: 6.240, year: 2021
Method of publishing: Open access with time embargo
https://doi.org/10.1051/0004-6361/202039661

We aim to investigate the existence of a critical value of the vertical magnetic field on a pore boundary and its role in the evolution of the magnetic structure. We observe well-defined stages in the pore evolution: (1) during the initial formation phase, total magnetic field strength (B) and vertical magnetic field ( Bver) increase to their maximum values of similar to 1920G and similar to 1730 G, respectively (2) then the pore reaches a stable phase (3) in a second formation phase, the pore undergoes a rapid growth in terms of size, along with a decrease in B and Bver on its boundary. In the newly formed area of the pore, Bver remains mostly below 1731G and B remains everywhere below 1921 G (4) ultimately, pore decay starts. We find overall that pore areas with Bver < 1731 G, or equivalently B < 1921 G, disintegrate faster than regions that fulfil this criteria. We find that the most stable regions of the pore, similarly to the case of umbral boundaries, are defined by a critical value of the vertical component of the magnetic field that is comparable to that found in stable sunspots. In addition, in this case study, the same pore areas can be similarly well-defined by a critical value of the total magnetic field strength.
Permanent Link: http://hdl.handle.net/11104/0324093