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Cluster Mission Operations

Ferri, P.; Warhaut, M.

Nonlinear electromagnetic waves and spherical arc-polarized waves in space plasmas

Neubauer, Fritz M.; Tsurutani, Bruce T.; Glassmeier, Karl-Heinz +3 more

We review observations of nonlinear plasma waves detected by interplanetary spacecraft. For this paper we will focus primarily on the phase-steepened properties of such waves. Plasma waves at comet Giacobini - Zinner measured by the international cometary explorer (ICE), at comets Halley and Grigg - Skjellerup measured by Giotto, and interplanetar…

Interactive Deconvolution with Error Analysis (IDEA) in astronomical imaging: Application to aberrated HST images on SN 1987A, M 87 and 3C 66B

Roques, S.; Fraix-Burnet, D.; Bouyoucef, K.

The regularized reconstruction algorithm {Interactive Deconvolution with Error Analysis} (IDEA) is presented. One of its main advantages is to control the error propagation and to provide an estimation of the quality of the deconvolved image. IDEA is compared with two popular probabilistic methods: Richardson-Lucy and Maximum Entropy. These three …

Estimate of the Energy Flux from Time-Distance Analysis

Ryutova, M.

In this Letter we show that time-distance measurements in helioseismology can be used to estimate the energy flux on the solar surface. Nonreciprocity of travel time along the ray path and different parity properties of sound speed, flow velocity, and magnetic field allow one to obtain information on large-scale distribution of plasma flows and ma…

Low frequency plasma waves in the solar wind: from ecliptic plane to the solar polar regions

Balogh, A.; Forsyth, R. J.; Lin, Naiguo +4 more

<B>Traveling from the ecliptic to the solar polar regions, Ulysses observed wave activity below the local electron cyclotron frequency, f_ce. In regions near the heliospheric current sheet (hereafter HCS regions), two wave modes are observed: (1) whistler mode electromagnetic waves near interplanetary shocks and during periods of rapidly inc…

High Resolution Measurements of the Isotopic Composition of Galactic Cosmic Ray C, N, O, Ne, Mg and Si from the Ulysses HET

Connell, J.

Observations of Energetic Ions During the Ulysses Mission

Sanderson, T. R.

The Ulysses spacecraft was launched in October 1990, and, having completed its prime mission to overfly the south and north polar regions of the Sun, has now started on its second solar orbit. We review here energetic ion observations from the many regions encountered during the out-of-ecliptic phase of the mission: the low latitude traversal of t…

Solar origin of the 26-day periodicity observed by Ulysses

Weber, M.; Hoeksema, J. T.; Acton, L. W. +1 more

The Ulysses spacecraft discovered that the interplanetary magnetic sector structure went through a major restructuring in mid-1992. The observed recurrence period changed from about 25.4 days to about 26.2 days. Another interesting discovery is that the solar wind speed, energetic particle fluxes, and interplanetary magnetic field all varied quasi…

Giantic Roundchroms of Binary Systems SX CAS and 22 VUL

Gurzadyan, G. A.

The IUE observations do not favor the chromospheric origin of typical chromospheric emission lines, of the doublet 2800 MgII first of all, in close binary systems SX Cas and 22 Vul, both with a cool giant-supergiant as primary, and a hot B7–B8 star as secondary. Here, it is shown that the concept of common chromospheres – roundchroms can explain t…

Energetic particle anisotropies and remote magnetic connection at high solar latitudes

Fränz, M.; Keppler, E.; Burgess, D. +2 more

A very stable pattern of energetic particle events recurring with the solar rotation period dominates the Ulysses high latitude energetic particle observations during the current solar minimum. Most of these events can be associated with reverse shocks of corotating interaction regions (CIRs) but at latitudes above 50 deg there are either no shock…