Astrophysical: Solar atmosphere

  • Publication
    Observation and interpretation of the asymmetric Stokes Q, U, and V line profiles in sunspots
    We present a first approach to systematic characterization and interpretation of observed asymmetries of Stokes profiles as a function of spatial position...
  • Publication
    Observations of the phase differences between irradiances and velocity for low-degree solar acoustic modes
    Irradiance measurements from the IPHIR instrument flown on the Phobos 2 mission to Mars are used to derive phase differences and gains between broadband...
  • Publication
    Observed differences between large and small sunspots
    We confirm recent results about the differences in temperature and magnetic field strength between the umbra of large and small sunspots. Five Stokes I- and V...
  • Publication
    On the Formation of Lyman β and the O I 1027 and 1028 Å Spectral Lines
    We study the potential of Lyman β and the O I 1027 and 1028 Å spectral lines to help in understanding the properties of the chromosphere and transition region...
  • Publication
    On the Magnetic Nature of Quiet-Sun Chromospheric Grains
    Ca II K grains, i.e., intermittent, short-lived (about 1 minute), periodic (2-4 minutes), pointlike chromospheric brightenings, are considered to be the...
  • Publication
    On the photospheric temperature in small-scale magnetic flux concentrations
    Results are presented of 2D radiative transfer calculations performed for geometric configurations that simulate partly evacuated small-scale magnetic flux...
  • Publication
    On the relation between the intensities of bright features and the local background in sunspot umbrae
    A photometric study of umbral bright features (umbral dots, clusters of umbral dots, bright grains of light bridges) in sunspots is presented. It is based on...
  • Publication
    On the temperature and velocity through the photosphere of a sunspot penumbra
    We investigate the structure in depth of a sunspot penumbra by means of the inversion code of the radiative transfer equation proposed by Ruiz Cobo & del Toro...
  • Publication
    Phase differences between irradiance and velocity low degree solar acoustic modes revisted
    Sine 1984, simultaneous observations of irradiance and velocity solar acoustic modes, have been carried out by several authors in order to measure the phase...