Context. Intermediate-mass, magnetic chemically peculiar (Ap) stars provide a unique opportunity to study the topology of stellar magnetic fields in detail and to investigate magnetically driven processes of spot formation. Aims: Here we aim to …
Context. High-resolution spectropolarimetric observations provide simultaneous information about stellar magnetic field topologies and three-dimensional distributions of chemical elements. High- quality spectra in the Stokes IQUV parameters are …
Context. Several recent spectrophotometric studies failed to detect significant global magnetic fields in late-B HgMn chemically peculiar stars, but some investigations have suggested the presence of strong unstructured or tangled fields in these …
Context. Mercury-manganese (HgMn) stars have been considered as non- magnetic and non-variable chemically peculiar (CP) stars for a long time. However, recent discoveries of the variability in spectral line profiles have suggested an inhomogeneous …
Context. Chemically peculiar stars of the mercury-manganese (HgMn) type represent a new class of spotted late-B stars, in which evolving surface chemical inhomogeneities are apparently unrelated to the presence of strong magnetic fields but are …
Mercury-manganese (HgMn) stars were considered to be non-magnetic, showing no evidence of surface spots. However, recent investigations revealed that some stars in this class possess an inhomogeneous distribution of chemical elements on their …
Context. According to our current understanding, a subclass of the upper main-sequence chemically peculiar stars, called mercury- manganese (HgMn), is non-magnetic. Nevertheless, chemical inhomogeneities were recently discovered on their surfaces. At …
Context. A subclass of the upper main-sequence chemically peculiar stars, mercury-manganese (HgMn) stars were traditionally considered to be non-magnetic, showing no evidence of variability in their spectral line profiles. However, discoveries of …