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The Ulysses fast latitude scans: COSPIN/KET results
Kunow, H.; Wibberenz, G.; Posner, A. +6 more
Ulysses, launched in October 1990, began its second out-of-ecliptic orbit in December 1997, and its second fast latitude scan in September 2000. In contrast to the first fast latitude scan in 1994/1995, during the second fast latitude scan solar activity was close to maximum. The solar magnetic field reversed its polarity around July 2000. While t…
Advances in magnetospheric radio wave analysis and tomography
Gurnett, D. A.; Escoubet, C. P.; Pickett, J. S. +7 more
Initial theoretical studies of multi-spacecraft radio tomographic imaging of the magnetosphere have shown the potential scientific value of the technique. We report a series of multistatic radio propagation experiments with the goal of testing and verifying the capabilities of radio tomography. These experiments focused specifically on measuring t…
Balmer absorption variability and the disc wind of V592 Cassiopeiae
Prinja, R. K.; Wagner, R. M.; Howell, S. B. +1 more
We present results from time-series optical spectroscopy of the low-inclination, nova-like cataclysmic variable, V592 Cas. The data span the wavelength range from ~4000 to 5000 Å, and include Balmer lines (Hβ to Hɛ) as well as He I and He II. The Balmer lines are generally characterized by shallow absorption troughs with superimposed narrower cent…
A Detailed Analysis of the Operational Orbit of the Hipparcos Satellite
van Leeuwen, Floor; Dalla Torre, Andrea
An analysis of the orbital evolution of the ESA's Hipparcos satellite is presented. Hipparcos operated between August 1989 and March 1993 in a highly elliptical orbit: a geostationary transfer orbit with increased perigee height. The requirements of the scientific mission included high accuracy knowledge of the position and velocity vectors of the…
Time resolved spectroscopy of GRB 030501 using INTEGRAL
Götz, D.; Mereghetti, S.; von Kienlin, A. +8 more
The gamma-ray instruments on-board INTEGRAL offer an unique opportunity to perform time resolved analysis on GRBs. The imager IBIS allows accurate positioning of GRBs and broad band spectral analysis, while SPI provides high resolution spectroscopy. GRB 030501 was discovered by the INTEGRAL Burst Alert System in the ISGRI field of view. Although t…
Variability of the H_alpha and Na I D Line Profiles in the Spectrum of FU Ori
Errico, L.; Lamzin, S. A.; Vittone, A.
The variations of line profiles in the spectrum of FU Ori during several consecutive nights, from January 3 through January 8, 1999, have been traced for the first time in the entire history of studying this star. The variations of the H_alpha and Na I D line profiles are regular in pattern; at each time, the profiles of these lines were similar t…
Hubble Space Telescope Observations of the Old Nova DI Lacertae
Szkody, Paula; Sion, Edward M.; Starrfield, Sumner +3 more
We have carried out a synthetic spectral analysis of a Hubble Space Telescope Space Telescope Imaging Spectrograph observation of the old nova DI Lacertae (Nova Lacerta 1910). The spectrum, obtained with the E140M disperser, reveals a rising continuum shortward of 1560 Å, a C IV P Cygni profile indicative of wind outflow associated with disk accre…
XMM-Newton Observation of Fe Kα Emission from a Broad Absorption Line Quasar: Markarian 231
Turner, T. J.; Kraemer, S. B.
We present results from a 20 ks XMM-Newton observation of Mrk 231. The European Photon Imaging Camera (EPIC) spectral data reveal strong line emission due to Fe Kα, which has rarely been detected in this class, as broad absorption line quasars (BAL QSOs) are very faint in the X-ray band. The line energy is consistent with an origin in neutral Fe. …
Optimal Masks for Solar g-Mode Detection
Kosovichev, A. G.; Scherrer, P. H.; Schou, J. +1 more
The detection of gravity (g) modes of solar oscillations is important for probing the physical conditions in the Sun's energy-generating core. We have developed a new method of spatial masks optimized to reveal solar g-modes of angular degree l=1-3 and applied it to Michelson Doppler Imager data in the frequency range of 50-500 µHz. These ma…
Atomic Data and Spectral Line Intensities for Si VII
Bhatia, A. K.; Landi, E.
Electron impact collision strengths, energy levels, oscillator strengths, and spontaneous radiative decay rates are calculated for the Si VII configurations 2s22p4, 2s2p5, 2p6, 2s22p33s, 2s22p33p, and 2s22p33d, giving rise to 86 fine-struc…