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Steps towards a virtual solar observatory
Csillaghy, A.; Freeland, S. L.; Zarro, D. M.
Intermediate-Brightness Spectrophotometric Standards. Standards Near +40° Declination
Tereshchenko, V. M.
The second stage in our program to compile a list of regional intermediate-brightness spectrophotometric standards has been completed. We have obtained spectral energy distributions for 24 stars with magnitudes near +40° declination. The range λλ3100 7600 Å was studied with a spectral resolution of 50 Å. The relative rms error of our results in th…
Solar Origin of Anisotropic Electron Events observed by ULYSSES and ACE
Pick, M.; Hawkins, S. E., III; Maia, D.
We investigate the solar origin of energetic collimated electron events observed in situ by the EPAM and/or HISCALE particle experiments aboard the ACE and ULYSSES spacecraft, respectively. This study has been performed for two months, September and October 1999 when Ulysses was magnetically connected to the solar disk at heliolongitudes visible a…
Quasi-thermal Noise Spectra Measured by a Dipole Antenna in the Upper Hybrid frequency band
Chugunov, Yury V.; Kazarova, Anna Yu.; Mareev, Eugene A. +3 more
Quasi-thermal noise (QTN) spectroscopy is one of the most effective tools for in situ diagnostics in space plasmas (Meyer-Vernet et al., 1998; Meyer-Vernet and Perche, 1989; Chugunov and Trakhtengerts, 1978). This method produces routine measurements of the bulk electron density and temperature; recently it has been extended to measure the ion bul…
Latitudinal transport of 7 MeV Jovian and galactic electrons in the inner heliosphere
Fichtner, H.; Ferreira, S. E. S.; Potgieter, M. S. +2 more
The heliospheric modulation of galactic and Jovian electrons is studied using a fully three-dimensional, steady-state model based on Parker's transport equation including the Jovian source. The model is used to study the latitudinal transport of both 7 MeV Jovian and galactic electrons by illustrating how the electron intensities are affected at d…
HD 169981 - an overlooked photometric binary?
Lehmann, H.; Scholz, G.; Hildebrandt, G. +1 more
In 1999 and 2000 we obtained spectroscopic and photometric observations of the A-type binary star HD 169981. The observations were part of a campaign to search for short-term photometric and radial-velocity variations among early-type binaries. From the radial velocities of 18 metal lines we derived more precise orbital elements. Quite unexpectedl…
The Evolution of the Anomalous Cosmic Ray Oxygen Spectra From 1995 to 1998: Ulysses Observations
Fränz, M.; Keppler, E.; Heber, B. +3 more
Moraal and Steenberg (1999), showed that the peak energy in the anomalous cosmic ray spectra is independent of the radial distance up to a few AU away from the termination shock but dependent on the solar wind speed, the radius of the termination shock and the scattering strength. In this paper we will discuss the variation of the cosmic ray oxyge…
The comparative accuracy of photographic observations of radio stars observed at the Engelhardt Astronomical Observatory
Rizvanov, N.; Dautov, I.; Shaimukhametov, R.
At the Engelhardt Astronomical Observatory (EAO), we observed photographic positions of 113 Galactic Radio Sources (GRS) in the system PPM catalogue (Rizvanov & Dautov 1998). Analysis of their accuracy is made by comparison with the Hipparcos catalogue (Perryman et al. 1997) and astrometric catalogue of radio stars in the radio window from the…
Solar rotation rate from minimum to maximum of activity cycle
Kumar, Brajesh; Tripathy, S. C.; Jain, Kiran +1 more
Using helioseismic data from SOI/MDI and GONG for the current solar cycle 23, from solar minimum to near maximum phase, we report here on the temporal variation of the rotation rate.
The Media Calibration System for Cassini Radio Science: Part III
Keihm, S. J.; Resch, G. M.; Lanyi, G. E. +5 more
A new media calibration system has been implemented at DSS 25. It is designed to calibrate the delay of radio signals imposed by the neutral atmosphere. The system provides periodic measurements, with intervals greater than 2 s, of both the static dry and fluctuating wet components of this delay. In particular, a water vapor radiometer calibrates …