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Galactic stars belonging to the Of?p category are all strongly magnetic objects exhibiting rotationally modulated spectral and photometric changes on timescales of weeks to years. Five candidate Of?p stars in the Magellanic Clouds have been discovered, notably in the context of ongoing surveys of their massive star populations. Here we describe an investigation of their photometric behaviour, revealing significant variability in all studied objects on timescales of one week to more than four years, including clearly periodic variations for three of them. Their spectral characteristics along with these photometric changes provide further support for the hypothesis that these are strongly magnetized O stars, analogous to the Of?p stars in the Galaxy.
We present UBVRI photometry of three symbiotic stars ZZ CMi, TX CVn and AG Peg carried out from 1997 to 2008 in Piwnice Observatory near Torun. To search orbital periods of these stars Fourier analysis was used. For two of them, TX CVn and AG Peg, we
In this paper, we investigate the photometric variability of magnetic O-type stars. Such stars possess oblique, predominantly dipolar magnetic fields that confine their winds roughly axisymmetrically about the magnetic equator, thus forming a magneto
We intended to compile the most complete catalog of bona fide members and candidate members of the beta Pictoris association, and to measure their rotation periods and basic properties from our own observations, public archives, and exploring the lit
Fluorine (19F) abundances (or upper limits) are derived in six extragalactic AGB carbon stars from the HF(1-0) R9 line at 2.3358 mu in high resolution spectra. The stars belong to the Local Group galaxies LMC, SMC and Carina dwarf spheroidal, spannin
Massive star winds are important contributors to the energy, momentum and chemical enrichment of the interstellar medium. Strong, organized and predominantly dipolar magnetic fields have been firmly detected in a small subset of massive O-type stars.