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Recovery of the Orbital Parameters and Pulse Evolution of V0332+53 during a Huge Outburst
Torres, Diego F.; Zhang, Shu; Qu, Jin-Lu +1 more
The high-mass X-ray binary V0332+53 became active at the end of 2004, and the outburst was observed in hard X-rays by RXTE and INTEGRAL. Based on these hard X-ray observations, we measure the orbital parameters by fitting the Doppler-shifted spin periods. The derived orbital period and eccentricity are consistent with those obtained by Stella et a…
Physical Conditions in the Narrow-Line Region of Markarian 3. I. Observational Results
Collins, Nicholas R.; Crenshaw, D. Michael; Bruhweiler, Frederick C. +3 more
We use Hubble Space Telescope Space Telescope Imaging Spectrograph (STIS) long-slit low-resolution spectroscopy from 1150 to 10300 Å to study the physical conditions in the narrow-line region (NLR) of the Seyfert 2 galaxy Markarian 3. We find from the He II λ1640/λ4686 line ratio and the Balmer decrement that the extinction within Mrk 3 along the …
Discovery of Photospheric Germanium in Hot DA White Dwarfs
Vennes, Stéphane; Chayer, Pierre; Dupuis, Jean
We report the identification of Ge IV resonance lines in ultraviolet spectra of the hot DA white dwarfs Feige 24, G191-B2B, and GD 246. The lines originate in the stellar photosphere, and we measure low Ge/H abundance ratios ranging between -8.0 and -8.7. We also tentatively identify a resonance line of Sn IV blended with an Fe V line in the spect…
Morphology and geological structure of the western part of the Olympus Mons volcano on Mars from the analysis of the Mars Express HRSC imagery
Jaumann, R.; Head, J. W.; Neukum, G. +8 more
The images of the western part of Olympus Mons and adjacent plains acquired by the HRSC camera onboard the Mars Express spacecraft were studied. The morphology, topography, and color of the surface were investigated. The surface age was determined by the frequencies of impact craters. The examination of the HRSC images combined with an analysis of…
X-ray confirmation of the intermediate polar HT Cam
Mukai, K.; Haberl, F.; Gänsicke, B. T. +6 more
We report on the first pointed X-ray observations with XMM-Newton and RXTE satellites of the X-ray source RX J0757.0+6306 = HT Cam. We detect a strong 515 s X-ray modulation confirming the optical photometric period found in 1998, which definitively assigns this source to the intermediate polar class of magnetic cataclysmic variables. The lack of …
Warm flux tubes in the E-ring plasma torus: Initial Cassini magnetometer observations
André, N.; Russell, C. T.; Dougherty, M. K. +2 more
Initial Cassini magnetometer observations in the E-ring plasma torus reveal the presence of previously unreported diamagnetic decreases in the magnetic field. The decrease in magnetic pressure on these flux tubes implies the presence of additional plasma energy densities up to 1 keV/cm3. They are less stretched than surrounding flux tub…
Supernova Remnants in the Magellanic Clouds. VI. The DEM L316 Supernova Remnants
Chu, Y. -H.; Williams, R. M.
The DEM L316 system contains two shells, both with the characteristic signatures of supernova remnants (SNRs). We analyze Chandra and XMM-Newton data for DEM L316, investigating its spatial and spectral X-ray features. Our Chandra observations resolve the structure of the northeastern SNR (shell A) as a bright inner ring and a set of ``arcs'' surr…
Evidence for Gravitational Infall of Matter onto the Supermassive Black Hole in the Quasar PG 1211+143?
Turner, T. J.; Uttley, P.; Kraemer, S. +5 more
We report the detection of redshifted iron Kα absorption lines in the Chandra LETG spectrum of the narrow-line quasar PG 1211+143. The absorption lines are observed at 4.22 and 4.93 keV in the quasar spectrum, corresponding to 4.56 and 5.33 keV in the rest frame of PG 1211+143. From Monte Carlo simulations, the chance probability of both lines bei…
Energetic Electrons as a Field Line Topology Tracer in the High Latitude Boundary/CUSP Region: Cluster Rapid Observations
Balogh, A.; Daly, P. W.; Reme, H. +7 more
Energetic electrons (e.g., 50 keV) travel along field lines with a high speed of around 20 REs‑1. These swift electrons trace out field lines in the magnetosphere in a rather short time, and therefore can provide nearly instantaneous information about the changes in the field configuration in regions of geospace. The energeti…
The young active binary star EK Draconis
Guenther, E. W.; Hatzes, A. P.; Woitas, J. +1 more