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Long term variability of Cygnus X-1. VI. Energy-resolved X-ray variability 1999-2011
We present the most extensive analysis of Fourier-based X-ray timing properties of the black hole binary Cygnus X-1 to date, based on 12 years of bi-weekly monitoring with RXTE from 1999 to 2011. OurExpand
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X-ray resonant photoexcitation: linewidths and energies of Kα transitions in highly charged Fe ions.
Photoabsorption by and fluorescence of the Kα transitions in highly charged iron ions are essential mechanisms for x-ray radiation transfer in astrophysical environments. We study photoabsorption dueExpand
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An unexpectedly low oscillator strength as the origin of the Fe xvii emission problem
Highly charged iron (Fe16+, here referred to as Fe xvii) produces some of the brightest X-ray emission lines from hot astrophysical objects, including galaxy clusters and stellar coronae, and itExpand
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Long term variability of Cygnus X-1
We present a scheme for determining the spectral state of the canonical black hole Cyg X-1 using data from previous and current X-ray all sky monitors (RXTE-ASM, Swift-BAT, MAXI, and Fermi-GBM).Expand
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Chandra X-ray spectroscopy of the focused wind in the Cygnus X-1 system III. Dipping in the low/hard state.
We present an analysis of three Chandra High Energy Transmission Gratings observations of the black hole binary Cyg X-1/HDE 226868 at different orbital phases. The stellar wind that is powering theExpand
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Chandra X-ray spectroscopy of focused wind in the Cygnus X-1 system - II. The non-dip spectrum in the low/hard state – modulations with orbital phase
Accretion onto the black hole in the system HDE 226868/Cygnus X-1 is powered by the strong line-driven stellar wind of the O-type donor star. We study the X-ray properties of the stellar wind in theExpand
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The Evolution of the South Atlantic Anomaly Measured by RHESSI
The South Atlantic Anomaly (SAA) is a region that contains an increased particle background due to a local minimum of the geomagnetic field. Because of this relation the trapped radiation follows theExpand
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Lineshape spectroscopy with a very high resolution, very high signal-to-noise crystal spectrometer.
We have developed a high-resolution x-ray spectrometer for measuring the shapes of spectral lines produced from laser-irradiated targets on the Orion laser facility. The instrument utilizes aExpand
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Calibration of the OHREX high-resolution imaging crystal spectrometer at the Livermore electron beam ion traps.
We report the calibration of the Orion High-Resolution X-ray (OHREX) imaging crystal spectrometer at the EBIT-I electron beam ion trap at Livermore. Two such instruments, dubbed OHREX-1 and OHREX-2,Expand
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Extended-range grazing-incidence spectrometer for high-resolution extreme ultraviolet measurements on an electron beam ion trap.
A high-resolution grazing-incidence grating spectrometer has been implemented on the Livermore electron beam ion traps for performing very high-resolution measurements in the soft x-ray and extremeExpand
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