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Observations of the Acceleration of Polar Solar Wind Near Solar Maximum

Simnett, G. M.; Tappin, S. J.; Lyons, M. A.

In a previous paper (Tappin et al., 1999) we used cross-correlation analysis of high-cadence observations with the LASCO coronagraphs to trace the acceleration of the solar wind at low latitudes. In this paper we present a similar analysis carried out over the North pole of the Sun. The observations which were made in March 2000 with the C3 corona…

Ulysses High Energy Telescope Measurements of the Isotopic Abundances of Galactic Cosmic Rays for Elements between C and Fe with Estimates of the Source Composition

Connell, J. J.

We report new and revised high resolution measurements of the isotopic composition of Galactic cosmic rays in the Solar system using data from the High Energy Telescope (HET) on the Ulysses Spacecraft. These data have significantly improved statistics compared with our earlier measurements. Mass resolution varies from ~0.08 to ~0.31 u at observed …

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…