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
    Magnetic Fields in a Sample of Planet-hosting M Dwarf Stars from Kepler, K2, and TESS Observed by APOGEE
    Stellar magnetic fields have a major impact on space weather around exoplanets orbiting low-mass stars. From an analysis of Zeeman-broadened Fe I lines measured...
  • Publication
    Magnetic Fields in M-dwarf Members of the Pleiades Open Cluster Using APOGEE Spectra
    Average magnetic field measurements are presented for 62 M-dwarf members of the Pleiades open cluster, derived from Zeeman-enhanced Fe I lines in the H band. A...
  • 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...