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NEXXUS: A comprehensive ROSAT survey of coronal X-ray emission among nearby solar-like stars
We present a final summary of all ROSAT X-ray observations of nearby stars. All available ROSAT observations with the ROSAT PSPC, HRI and WFC have been matched with the CNS4 catalog of nearby starsExpand
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X-ray emission from classical T Tauri stars: Accretion shocks and coronae?
Classical T Tauri stars (CTTS) are surrounded by actively accreting disks. According to current models material falls along the magnetic field lines from the disk with more or less free-fall velocityExpand
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X-ray accretion signatures in the close CTTS binary V4046 Sgr
We present Chandra HETGS observations of the classical T Tauri star (CTTS) V4046 Sgr. The He-like triplets of Ovii, Neix, and Sixiii are clearly detected. Similar to the CTTS TW Hya and BP Tau, theExpand
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Multi-wavelength observations of Proxima Centauri
Aims. We report simultaneous observations of the nearby flare star Proxima Centauri with VLT/UVES and XMM-Newton over three nights in March 2009. Our optical and X-ray observations cover the star’sExpand
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Multiwavelength observations of a giant flare on CN Leonis - I. The chromosphere as seen in the optical spectra
Aims. Flares on dM stars contain plasmas at very different temperatures and thus affect a wide wavelength range in the electromagnetic spectrum. While the coronal properties of flares are studiedExpand
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X-ray emission from the ultracool dwarf LHS 2065
We report the results of a 68 ks long X-ray observation of the M9V ultracool dwarf star LHS 2065 with the ROSAT high resolution imager (HRI). During the observations a major X-ray flare occurred withExpand
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Recruitment Behavior in the Ant Genus Polyrhachis (Hymenoptera, Formicidae)
We present a detailed behavioral analysis of the signals involved in recruitment of 11 syntopic Polyrhachis species from West Malaysia. We found a considerable variety of recruitment techniques,Expand
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Coronal properties of the EQ Pegasi binary system
Context. The activity indicators of M dwarfs are distinctly different for early and late types. The coronae of early M dwarfs display high X-ray luminosities and temperatures, a pronounced inverseExpand
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The coronal Ne/O abundance of alpha Centauri
Recent improvements in the modeling of solar convection and line formation led to downward revisions of the solar photospheric abundances of the lighter elements, which in turn led to changes in theExpand
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Nesting and food resources of syntopic species of the ant genus Polyrhachis (Hymenoptera, Formicidae) in West-Malaysia
Summary:Polyrhachis is one of the largest ant genera in the world distributed in the Old World tropics and subtropics. We investigated the nesting and nutrition habits of 10 syntopic species ofExpand
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