Context. Recently, unanticipated magnetic activity in ultracool dwarfs (UCDs, spectral classes later than M7) has emerged from a number of radio observations. The highly (up to 100%) circularly polarized nature and high ...

Context. Radio data obtained for the ultracool dwarf TVLM 513-46546 has indicated a rotation period of approximate to 1.96 h via regular radio pulses, but how stable is this period. This has major implications regarding ...