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Gamma-ray observations of explosive nucleosynthesis products
Vink, Jacco
In this review I discuss the various γ-ray emission lines that can be expected and, in some cases have been observed, from radioactive explosive nucleosynthesis products. The most important γ-ray lines result from the decay chains of 56Ni, 57Ni, and 44Ti. 56Ni is the prime explosive nucleosynthesis produ…
A mapping of martian water sublimation during early northern summer using OMEGA/Mars Express
Bibring, J. -P.; Gondet, B.; Langevin, Y. +8 more
The OMEGA imaging spectrometer aboard Mars Express has been used to map the water vapor abundance over the martian surface, from the analysis of the 2.6 µm band of H2O. As a preliminary result of this study, we present water vapor maps in the northern hemisphere at the time of the northern polar cap sublimation (Ls = 94-112 deg). The maps sh…
Discovery of X-ray eclipses from the transient source CXOGC J174540.0-290031 with XMM-Newton
Grosso, N.; Warwick, R. S.; Porquet, D. +4 more
We present the XMM-Newton observations obtained during four revolutions in Spring and Summer 2004, of CXOGC J174540.0-290031, a moderately bright transient X-ray source, located at only 2.9'' from Sgr A*. We report the discovery of sharp and deep X-ray eclipses, with a period of 27 961±5 s and a duration of about 1100±100 s, observed during the tw…
The heliospheric modulation of 3 10 MeV electrons: Modeling of changes in the solar wind speed in relation to perpendicular polar diffusion
Fichtner, H.; Ferreira, S. E. S.; Potgieter, M. S. +3 more
The discrepancy between cosmic ray model predictions representing solar minimum conditions in the heliosphere and the 3-10 MeV post-1998 electrons observations by the Kiel Electron Telescope (KET) onboard Ulysses suggests the need for consistent changes in model parameters with increasing solar activity. In order to reduce this discrepancy, an eff…
Observations of Hα Intensity Oscillations in a Flare Ribbon
Gallagher, Peter T.; Mathioudakis, Mihalis; Bloomfield, D. Shaun +6 more
High-cadence Hα blue wing observations of a C9.6 solar flare obtained at Big Bear Solar Observatory using the Rapid Dual Imager are presented. Wavelet and time-distance methods were used to study oscillatory power along the ribbon, finding periods of 40-80 s during the impulsive phase of the flare. A parametric study found statistically significan…
Transient Coronal Holes as Seen in the He I 1083 nm MLSO Observations
de Toma, G.; Holzer, T. E.; Burkepile, J. T. +1 more
Observations from Yohkoh SXT and SOHO EIT have shown that dimming regions often appear on the solar disk near the location of a coronal mass ejection (CME). We now can see brightenings in He I 1083 nm observations made at the Mauna Loa Solar Observatory (MLSO) that form at the same time and are cospatial with the EUV intensity dimmings observed fr…
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…