On the Putative Detection of z>0 X-ray Absorption Features in the Spectrum of Markarian 421

Kavli Affiliate: Andrew P. Rasmussen | First 5 Authors: Andrew P. Rasmussen, Steven M. Kahn, Frits Paerels, Jan Willem den Herder, Jelle Kaastra | Summary: In a series of papers, Nicastro et al. have reported the detection of z>0 OVII absorption features in the spectrum of Mrk421 obtained with the Chandra Low Energy Transmission Grating […]


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X-ray flare modeling in the single giant HR 9024

Kavli Affiliate: David Huenemoerder | First 5 Authors: Paola Testa, David Garcia-Alvarez, Fabio Reale, David Huenemoerder, | Summary: We analyze a Chandra-HETGS observation of the single G-type giant HR 9024. The high flux allows us to examine spectral line and continuum diagnostics at high temporal resolution, to derive plasma parameters (thermal distribution, abundances, temperature, …). […]


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Objective Subclass Determination of Sloan Digital Sky Survey Unknown Spectral Objects

Kavli Affiliate: Mark SubbaRao | First 5 Authors: David Bazell, David J. Miller, Mark SubbaRao, , | Summary: We analyze a portion of the SDSS photometric catalog, consisting of approximately 10,000 objects that have been spectroscopically classified into stars, galaxies, QSOs, late-type stars and unknown objects (spectroscopically unclassified objects, SUOs), in order to investigate the […]


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A Galactic Origin for the Local Ionized X-ray Absorbers

Kavli Affiliate: Claude Canizares | First 5 Authors: Taotao Fang, Christopher McKee, Claude Canizares, Mark Wolfire, | Summary: Recent Chandra and XMM observations of distant quasars have shown strong local (z~0) X-ray absorption lines from highly ionized gas, primarily He-like oxygen. The nature of these X-ray absorbers, i.e., whether they are part of the hot […]


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Teaching General Relativity

Kavli Affiliate: Robert Wald | First 5 Authors: Robert M. Wald, , , , | Summary: This Resource Letter provides some guidance on issues that arise in teaching general relativity at both the undergraduate and graduate levels. Particular emphasis is placed on strategies for presenting the mathematical material needed for the formulation of general relativity. […]


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The First Chandra Field

Kavli Affiliate: Robert A. Cameron | First 5 Authors: Martin C. Weisskopf, Thomas L. Aldcroft, Robert A. Cameron, Poshak Gandhi, Cédric Foellmi | Summary: Before the official first-light images, the Chandra X-Ray Observatory obtained an X-ray image of the field to which its focal plane was first exposed. We describe this historic observation and report […]


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Exclusion Limits on the WIMP-Nucleon Cross-Section from the First Run of the Cryogenic Dark Matter Search in the Soudan Underground Lab

Kavli Affiliate: Clarence Chang | First 5 Authors: CDMS Collaboration, , , , | Summary: The Cryogenic Dark Matter Search (CDMS-II) employs low-temperature Ge and Si detectors to seek Weakly Interacting Massive Particles (WIMPs) via their elastic scattering interactions with nuclei. Simultaneous measurements of both ionization and phonon energy provide discrimination against interactions of background […]


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Discovery of Oxygen Kalpha X-ray Emission from the Rings of Saturn

Kavli Affiliate: Peter G. Ford | First 5 Authors: Anil Bhardwaj, Ronald F. Elsner, J. Hunter Waite, Jr., G. Randall Gladstone, Thomas E. Cravens | Summary: Using the Advanced CCD Imaging Spectrometer (ACIS), the Chandra X-ray Observatory (CXO) observed the Saturnian system for one rotation of the planet (~37 ks) on 20 January, 2004, and […]


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