Astrophysical: Stellar magnetic fields

  • Publication
    Giant white-light flares on fully convective stars occur at high latitudes

    In a systematic analysis of fully convective stars observed with TESS, we detected four stars that displayed giant flares that were...

  • Publication
    Instrumental polarization in the focal plane of telescopes. 2: Effects induced by seeing

    This work quantifies the influence of the terrestrial atmosphere on the instrumental polarization (IP) of telescopes. Our numerical simulations show that seeing...

  • Publication
    Non-local thermodynamic equilibrium line profiles, rotation, and magnetic fields in seven DA white dwarfs

    Non-LTE calculations of H-alpha line profiles are presented and applied to derive rotational velocities from high-resolution spectra of DA white dwarfs. This...

  • 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
    The age decay of stellar magnetic activity in MS field solar-type stars

    The age decay of two indicators of the stellar magnetic activity (λ2800 Mg II emission flux and λ10830 He I equivalent width) have been studied for field solar...

  • Publication
    The magnetic field of the AP star Epsilon UMa

    The magnetic field of the Ap star Epsilon UMa was measured using the Zeeman-Doppler Imaging method. Ultrahigh S/N polarized profiles of the 4923 A magnetically...

  • Publication
    The Origin of Weakened Magnetic Braking in Old Solar Analogs

    The rotation rates of main-sequence stars slow over time as they gradually lose angular momentum to their magnetized stellar winds. The rate of angular momentum...