Astrophysical: Solar activity

  • Publication
    Circular polarization of the CA II H and K lines in solar quiet and active regions
    A representative set of profiles is presented for the Ca II H resonace line in Stokes V and I, for the quiet sun, plages, sunspot umbrae, and a flare, as well...
  • Publication
    Comparison of parameters of low l solar p-modes at maximum and minimum activity
    Velocity measurements of disk integrated sunlight obtained by GOLF experiment aboard SOHO are used to find the parameters of solar p-modes (l
  • Publication
    Continuum intensity and magnetic flux of solar fluxtubes
    The continuum contrast between flux tubes and their quiet background, and the magnetic flux carried by these magnetic elements, have been determined at...
  • Publication
    Decay rates of sunspot groups from 1874 to 1976
    The global behavior and fine structure of the distribution of sunspot decay rates from activity cycle 13 to 20 are presented. It is shown that the distribution...
  • Publication
    Detailed processes accompanying the decay of an active region
    The decay of a small solar active region is studied with high-resolution magnetograms. The reduction process made it possible to match intensity and magnetic...
  • Talk
    Dynamos, the drivers of solar and stellar activity
    Following Cowling's anti-dynamo theorem of 1933, there was a long period during which the very existence of dynamos was unclear. Even with the emergence of...
  • Publication
    Exploring the Magnetic and Thermal Evolution of a Coronal Jet
    Coronal jets are the captivating eruptions that are often found in the solar atmosphere and primarily formed due to magnetic reconnection. Despite their short...
  • Publication
    Fragments in sunspots
    High-resolution white light and H-alpha observations are used to study the development of 15 large active solar regions. The behavior of the magnetic fragments...
  • Publication
    Frequency shift of solar p-modes as seen by cross correlation analysis
    Data obtained at the Observatorio del Teide (Tenerife) during the years 1978 to 1988 using a resonant scattering spectrophotometer, is analyzed to look for...