Estimation of Projection Effect of CMEs from the Onset Time of the Shock-Associated Type III Radio Burst

• Autorzy: Michałek G. , Gopalswamy N. , Yashiro S.
• Języki publikacji: EN

Abstrakty

EN

We present a new possibility to estimate the projection effects on coronal mass ejection (CME) measurements. It is well known that coronagraphic observations of CMEs are subject to projection effects. Fortunately, the WIND/WAVES observations of type III radio bursts associated with shock waves are free from projection effects. We assume that (1) high energy electrons are produced at the shock front ahead of the CME, and (2) the radio burst starts when the shock reaches open field lines (≈3 R_solar). In other words, the onset time of the radio burst corresponds to the time when the CME leading edge reaches 3 R_solar. The difference between the onset times of CMEs and radio bursts should be strongly correlated with the position of CMEs on the Sun. This correlation seems to be strongly dependent on solar activity. Using particular linear fits on the scatter plots, we can determine the source location of CMEs and tell how much the projection effect can really affect CME measurements.

Słowa kluczowe

EN

Sun: coronal mass ejections; CMEs; Sun: radio radiation

• Wydawca: Copernicus Foundation for Polish Astronomy
• Czasopismo: Acta Astronomica
• Rocznik: 2005
• Tom: Vol. 55, No. 1
• Strony: 151--158
• Opis fizyczny: Bibliogr. 12 poz., wykr.

Twórcy

autor

Michałek G.

• Astronomical Observatory of Jagiellonian University, ul. Orla 171, 30-244 Kraków, Poland
• Center for Solar and Space Weather, Catholic University of America, Washington, DC 20064

autor

Gopalswamy N.

• NASA Goddard Space Flight Center, Code 695, Greenbelt, MD 20771

autor

Yashiro S.

• Center for Solar and Space Weather, Catholic University of America, Washington, DC 20064

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