AbstractMeasurements of the motion of plasma density inhomogeneities in the inner solar wind are presented. The speeds were estimated using a cross-correlation analysis of radio frequency fluctuations of the Galileo spacecraft measured simultaneously at widely spaced ground stations. The radial projections of the correlation baselines on the pattern plane were of the order of several thousand kilometers. For cross-correlation functions calculated with comparatively short averaging times, we find that a pronounced two-velocity configuration is occasionally observed over the range of heliocentric distances 20 R⊙<R<40 R⊙. The typical mean speed for such observations is about 300–400 km/s and the difference between the two predominant speeds is about 150–200 km/s. These results may indicate that the density fluctuations are associated with slow magnetosonic waves propagating in opposite directions at the local speed of sound in the reference frame moving with the mean solar wind speed. Quite reasonable estimates of the solar wind speed and speed of sound are obtained from this model. Another possible explanation of the two-velocity structures is that two independent solar wind streams are present simultaneously along different segments of the radio ray path.


    Zugriff

    Zugriff prüfen

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Two-velocity structure observed in the inner solar wind


    Beteiligte:
    Chashei, I.V. (Autor:in) / Efimov, A.I. (Autor:in) / Samoznaev, L.N. (Autor:in) / Plettemeier, D. (Autor:in) / Bird, M.K. (Autor:in)

    Erschienen in:

    Advances in Space Research ; 35 , 12 ; 2195-2198


    Erscheinungsdatum :

    2004-11-17


    Format / Umfang :

    4 pages




    Medientyp :

    Aufsatz (Zeitschrift)


    Format :

    Elektronische Ressource


    Sprache :

    Englisch




    Two-velocity structure observed in the inner solar wind

    Chashei, I.V. | Online Contents | 2005


    Two-velocity structure observed in the inner solar wind

    Chashei, I. V. / Efimov, A. I. / Samoznaev, L. N. et al. | British Library Conference Proceedings | 2005


    Velocity of the Inner Solar Wind from Coronal Sounding Experiments with Spacecraft

    Efimov, A. I. / Lukanina, L. A. / Chashei, I. V. et al. | Online Contents | 2018


    Velocity of the Inner Solar Wind from Coronal Sounding Experiments with Spacecraft

    Efimov, A. I. / Lukanina, L. A. / Chashei, I. V. et al. | Springer Verlag | 2018


    On the enhanced velocity oscillations observed during solar flares

    Kumar, B. / Venkatakrishnan, P. / Venugopalan, K. et al. | British Library Conference Proceedings | 2006