@InProceedings{SantosWras:2018:PhVoFl,
               author = "Santos, Jean Carlo and Wrasse, Cristiano Max",
          affiliation = "{Universidade Tecnol{\'o}gica Federal do Paran{\'a} (UTFPR)} and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)}",
                title = "Photospheric vortex flows close to the polarity inversion line of 
                         a fully emerged active region",
                 year = "2018",
         organization = "Simp{\'o}sio Brasileiro de Geof{\'{\i}}sica Espacial e 
                         Aeronomia, 7. (SBGEA)",
             abstract = "We report on the occurrence of vortexes in flow fields obtained 
                         from the evolution of the line-of-sight component of the 
                         photospheric magnetic field in a region around the polarity 
                         inversion line (PIL) of a fully emerged active region. These 
                         vortexes are important because they may twist or interweave the 
                         magnetic field lines, injecting magnetic energy and helicity in 
                         the solar upper atmosphere. Based on a local linear approximation 
                         for the flow field, we identify the presence of critical points 
                         and classify them according to the eigenvalues of the Jacobian 
                         matrix of the linear transformation. Vortexes are associated to 
                         the presence of a particular kind of critical point, known as 
                         Attracting Focus. Using this method we identified twelve vortexes 
                         in the analyzed period and detected the occurrence of other types 
                         of critical points, which indicate the complexity of the flow 
                         field around the PIL. The detected vortexes show a clockwise 
                         preferred sense of rotation with approximately of the cases. A 
                         geometrical analysis of the velocity structures produced an 
                         average value of D = 1.63 ± 0.05 for the fractal dimension, which 
                         is very close to the one obtained for isotropic homogeneous 
                         turbulence (D = 5/3). This suggests that the flow around the 
                         polarity inversion line is turbulent in nature.",
  conference-location = "Santa Maria, RS",
      conference-year = "05-09 nov",
             language = "pt",
        urlaccessdate = "27 abr. 2024"
}