@InProceedings{BarbosaSilvCost:2022:StRoGy,
               author = "Barbosa, Abimael Amaro Xavier and Silva, Marlos Rockenbach da and 
                         Costa, Joaquim Eduardo Rezende",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)}",
                title = "Study of the role of the gyroresonance emission mechanism in the 
                         brightness intensification at 17 GHz of solar active regions",
                 year = "2022",
         organization = "COSPAR Scientific Assembly, 44.",
             abstract = "Associated with magnetic fields between the chromosphere and the 
                         corona, specifically in active regions, gyroresonance emission 
                         plays an important role in revealing the magnetic dynamics in such 
                         layers. This category of radio emission originates in the 
                         acceleration of thermally distributed electrons that spiral 
                         magnetic field lines. Then, given the magnetic association of this 
                         radiation, this work hypothesized the possible relationship of the 
                         gyroresonance mechanism with brightness bumps at radio 
                         frequencies. Such hypothesis was based on the control played by 
                         the magnetic field on the radio emission when such field reaches 
                         conditions conducive to gyroresonant radiation at given frequency 
                         and harmonic. To test such a hypothesis, we selected and observed 
                         8 active regions from the ascending phase of the 24th solar cycle. 
                         In this analysis, the data for these regions were HMI magnetograms 
                         from the Solar Dynamics Observatory (SDO) and images at 17 GHz 
                         from the Nobeyama Radioheliograph (NoRH). Although these 
                         magnetograms map only photospheric magnetic fields, they are 
                         useful for indicating where the intensity of these fields 
                         approaches values associated with the gyroresonant mechanism for a 
                         given frequency and harmonic of the radio emission. For each 
                         active region, then, we compiled both the SDO and NoRH maps of the 
                         same time and analyzed its magnetic field and brightness 
                         temperature. We then observed that the magnetic field conducive to 
                         the gyroresonance mechanism was partially or completely enveloped 
                         by the brightness bumps at 17 GHz. Furthermore, we also observed 
                         that most of these bumps had circular polarization modulus (jrCj) 
                         above 30% and that the brightness temperature of the selected 
                         active regions was strongly correlated with jrCj 30% while it was 
                         weakly or moderately correlated with jrCj < 30%. The results of 
                         this work therefore support the proposed hypothesis, which makes 
                         brightness bumps at 17 GHz useful means of identifying 
                         gyroresonance sources.",
  conference-location = "Athens, Greece",
      conference-year = "16-24 July 2022",
             language = "en",
           targetfile = "D2.3-0040-22-oral.pdf",
        urlaccessdate = "29 jun. 2024"
}