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ISOCAM Long Wave Detector Glitches: Data and Ray-Tracing Simulations

Nieminen, Petteri; Sørensen, John

The affected pixel number distribution of the ISOCAM Long-Wave (LW) detector in cosmic ray-induced glitches is calculated. The methods employed are Monte Carlo ray-tracing techniques and the taxi metric, which allows direct calculation of the affected pixels based on the knowledge of entry and exit points of the ray. The simulation results are com…

Photometric orbital modulation in V 1080 Tauri

Gális, R.; Šimon, V.; Hanžl, D. +1 more

We present a photometric study of the variable star V 1080 Tauri. All photometric data, spanning in total about 9 years, can be folded with the period of 8.8451741 days, yielding a single-wave course with the full amplitude of 0.14 mag. The Hipparcos data show that the secular trend in the brightness variations is not larger than 0.04 mag and that…

Europas Röntgenobservatorium XMM.

Schartel, N.; Dahlem, M.

In den letzten 25 Jahren haben sich Beobachtungen im Röntgenlicht, neben optischen und Radiobeobachtungen, zum dritten wichtigen Standbein der Astronomie entwickelt. Die Dynamik dieser Entwicklung zeigt sich darin, dass den Astronomen seit dem Start von ROSAT immer wenigstens zwei Röntgensatelliten zur selben Zeit zur Verfügung standen. Im nächste…

Radiance Variations of Vacuum-Ultraviolet Emission Lines of the Quiet Sun Observed with SUMER on SOHO

Wilhelm, K.; Lemaire, P.; Hollandt, J. +2 more

The Temperature of the Hot DB GD 190

Provencal, J. L.; Shipman, H. L.

We are currently in the midst of an investigation of hydrogen and carbon abundances in hot DB white dwarfs. Our HST UV spectra give evidence that hot DBs contain traces of carbon which can be used to determine the temperatures of these objects. We present the results of our investigation of GD 190.

Status of the draft ISO Solar Irradiance Standard

Tobiska, W. K.; Nusinov, A. A.

Radial Distance Dependence of the Solar Wind Speed at High Latitudes Observed by Interplanetary Scintillation

Tokumaru, M.; Kojima, M.; Yokobe, A.

We have investigated the radial distance dependence of the solar wind speed during the years 1995 and 1996 using interplanetary scintillation (IPS) observations at the Solar-Terrestrial Environment Laboratory. We derived solar wind velocity distributions for regions inside and outside of 0.3 AU separately using a computerized tomography method to …

Initial Results from the XUV Doppler Telescope

Kano, R.; Kobayashi, K.; Tsuneta, S. +6 more

We developed a unique telescope to obtain simultaneous XUV images and the velocity maps by measuring the line-of-sight Doppler shifts of the Fe XIV 211A&ring line (T = 1.8 MK): the Solar XUV Doppler Telescope (hereafter XDT). The telescope was launched by the Institute of Space and Astronautical Science with the 22nd S520 rocket on January 31,…

Recognition of Space Weather Impact on the Isophot Detectors

Klaas, Ulrich; Castañeda, Hector O.

The effects of changes in the space environment on the ISOPHOT photoconductive detectors over the whole ISO mission were studied using the complete set of responsivity check measurements taken after the curing of the detectors. We found that the responsivity of the Ge-based, low bias voltage far-infrared detectors (P3, C100, and C200) is sensitive…

Coupling of the high and low latitude heliosphere and its relation to the corona. Proceedings. D0.7 Symposium of COSPAR Scientific Commission D held during 32nd COSPAR Scientific Assembly, Nagoya (Japan), 12 - 19 Jul 1998.

Kunow, H.

The following topics were dealt with: solar wind acceleration, interplanetary scintillation measurements, solar wind structure, solar wind acceleration region, 3D MHD simulations of coronal mass ejections, interplanetary magnetic clouds, coronal streamers, plasma velocity in interplanetary magnetic structures, H cell measurements, polar plume and …