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Coronal Evolution of the Sun in Time: High-Resolution X-Ray Spectroscopy of Solar Analogs with Different Ages
We investigate the long-term evolution of X-ray coronae of solar analogs based on high-resolution X-ray spectroscopy and photometry with XMM-Newton. Six nearby main-sequence G stars with ages between
High-resolution X-ray spectroscopy of Procyon by Chandra and XMM-Newton
We report the analysis of the high-resolution soft X-ray spectrum of the nearby F-type star Procyon in the wavelength range from 5 to 175 A obtained with the Low Energy Transmission Grating
Coronal density diagnostics with Helium-like triplets: CHANDRA-LETGS observations of Algol, Capella, Procyon, epsilon Eri, alpha Cen A&B, UX Ari, AD Leo, YY Gem, and HR 1099
The authors' LETGS spectra are found to be an extremely useful tool for plasma diagnostics of stellar coronae and a correlation between line flux ratios of the Ly and He-like resonance lines with the mean X-ray surface flux is found.
On the sizes of stellar X-ray coronae
Spatial information from stellar X-ray coronae cannot be assessed directly, but scaling laws from the solar corona make it possible to estimate sizes of stellar coronae from the physical parameters
MAXI J1659-152: the shortest orbital period black-hole transient in outburst
MAXI J1659−152 is a bright X-ray transient black-hole candidate binary system discovered in September 2010. We report here on MAXI, RXTE, Swift, and XMM-Newton observations during its 2010/2011
Chandra-LETGS X-ray observation of α Centauri : A nearby (G2V + K1V) binary system
A Chandra LETGS X-ray observation of α Centauri with an exposure time of 81.5 ks is presented with the two components (K1V and G2V) spectrally resolved for the first time. We use the emission lines
X-rays from accretion shocks in T Tauri stars: The case of BP Tau
We present an XMM-Newton observation of the classical T Tauri star BP Tau. In the XMM-Newton RGS spectrum the O  triplet is clearly detected with a very weak forbidden line indicating high plasma
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, the
Swift Observations of the 2006 Outburst of the Recurrent Nova RS Ophiuchi. I. Early X-Ray Emission from the Shocked Ejecta and Red Giant Wind
RS Ophiuchi began its latest outburst on 2006 February 12. Previous outbursts have indicated that high-velocity ejecta interact with a preexisting red giant wind, setting up shock systems analogous
Swift X-ray observations of classical novae
This work analyzed all the observations of classical novae from the Swift archive up to 2006 June 30 and found 4 nondetections, 3 weak sources, and 5 strong sources, implying ongoing nuclear burning on the white dwarf surface.