Related papers: Stellar Coronal Spectroscopy with the Chandra HETG…
We present an analysis of the Chandra High Energy Transmission Grating Spectrometer observation of the rapidly rotating P_(rot)=0.94 d post T Tauri (~20 Myr old) star PZ Telescopii, in the Tucana association. Using two different methods we…
First results from high-resolution coronal spectroscopy of flares with the Reflection Grating Spectrometers on board the \textit{XMM-Newton} satellite are reviewed. Rotational modulation in the X-ray light curve of HR 1099 is discussed.…
Short-period binaries represent extreme cases in the generation of stellar coronae via a rotational dynamo. Such stars are important for probing the origin and nature of coronae in the regimes of rapid rotation and activity saturation. VW…
We report on the analysis of high resolution X-ray spectra of two pre-main-sequence stars: TWA 5 (observed with XMM-Newton) and PZ Telescopii (observed with Chandra/HETGS). TWA 5 is a classical T Tauri star in the TW Hydrae association…
The Chandra X-ray Observatory grating spectrometers allow study of stellar spectra at resolutions on the order of 1000. Prior x-ray observatories' low resolution data have shown that nearly all classes of stars emit x-rays. Chandra reveals…
The nearest accreting T Tauri star, TW Hya was observed with spectroscopic and photometric measurements simultaneous with a long se gmented exposure using the CHANDRA satellite. Contemporaneous optical photometry from WASP-S indicates a…
We used high-resolution near-infrared spectroscopy from the NIRSPEC instrument on the Keck II telescope, taken over multiple epochs spanning five years, to examine two young binary T Tauri star systems, S Corona Australis and VV Corona…
Chromospheric activity cycles are common in late-type stars; however, only a handful of coronal activity cycles have been discovered. \ihor\ is the most active and youngest star with known coronal cycles. It is also a young solar analog,…
We probe the relationship between surface magnetic fields and the X-ray emitting corona in the rapidly rotating star AB Dor. Circularly polarised spectra have been inverted to produce a surface (photospheric) magnetic field map. This…
We have analyzed GHRS data of eight Classical T Tauri stars (CTTSs) and one Weak T Tauri star (WTTS). The GHRS data consist of an spectral range 40 A wide centered on 2800 A. For 4 of the CTTS we have nearly simultaneous optical…
We have modelled the rotational modulation of X-ray emission from T Tauri stars assuming that they have isothermal, magnetically confined coronae. By extrapolating surface magnetograms we find that T Tauri coronae are compact and clumpy,…
We have modeled the rotational modulation of X-ray emission from T Tauri stars assuming that they have isothermal, magnetically confined coronae. By extrapolating surface magnetograms we find that T Tauri coronae are compact and clumpy,…
We present the X-ray spectrum of TW Hya observed at high and intermediate spectral resolution with the Reflection Grating Spectrometer (RGS) and the European Photon Imaging Camera (EPIC) onboard the XMM-Newton satellite. TW Hya is the first…
The Chandra High Energy Transmission Gratings (HETG) Orion Legacy Project (HOLP) is the first comprehensive set of observations of a very young massive stellar cluster which provides high resolution X-ray spectra of very young stars over a…
The X-ray luminous RS CVn binary system HR 1099 has been observed on several occasions in the early phases of \textit{Chandra} and \textit{XMM-Newton}. A very hot (up to 40 MK) dominant coronal plasma has been identified from the…
We present the work in progress of a study based on photometric and spectroscopic observations of young Weak-line T Tauri and Post T Tauri stars just attiving on the Zero Age Main Sequence. This study is part of a project based on…
(Abridged) The results of a Chandra X-ray Observatory High-Energy Transmission Grating (HETG) observation of the nova-like cataclysmic binary AE Aqr are described. First, the X-ray spectrum is that of an optically thin multi-temperature…
We present high-resolution X-ray spectra of the multiple (hierarchical quadruple) weak-lined T Tauri star system HD 98800, obtained with the High Energy Transmission Gratings Spectrograph (HETGS) aboard the Chandra X-ray Observatory (CXO).…
High-resolution X-ray spectra of high-mass stars and low-mass T-Tauri stars obtained during the first year of the Chandra mission are providing important clues about the mechanisms which produce X-rays on very young stars. For zeta Puppis…
Classical T Tauri stars (CTTS) are young (< 10 Myr), cool stars that actively accrete matter from a disk. They show strong, broad and asymmetric, atomic FUV emission lines. Neither the width, nor the line profile is understood. Likely,…