Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.sao.ru/cats/~satr/RFSymp/abs/19_Kotelnikov.pdf Дата изменения: Mon Oct 9 11:39:02 2006 Дата индексирования: Tue Oct 2 10:27:11 2012 Кодировка: Поисковые слова: comet tail

ABOUT A DOUBLE INVERSION SIGN OF POLARIZATION MICROWAVE EMISSION FROM FLARE-PRODUCTIVE ACTIVE REGION
V. Kotelnikov1 , V. Bogo d1 , L. Yasnov
1 2

Saint-Petersburg branch of Sp ecial Astrophysical Observatory of RAS Pulkovsko e Shosse, 65, Saint-Petersburg, Russia 2 Saint-Petersburg State University 198904 Saint-Petersburg, St. Peterhof, Ul'anovskaya street 1 vasian.spbu@mail.ru

Polarization inversions have b een detected in some microwave sources by Piddington et al. (1951) and by Peterova at al. (1974). Tokhchukova et al. (2002) have shown that a more complex phenomenon is observed in the flare-active regions: b efore a p owerful flare the sign of circular p olarization changed twice within a narrow frequency range. Here we discuss observations of flare-pro ductive active regions. These observations were carried out with the RATAN-600 radio telescop e in a broad radio range for a p erio d from 2000 to 2004. The double inversion has b een observed in several events b efore p owerful proton flares. We prop ose two alternative mo dels for explanation of this phenomenon. The first mo del is the existence of the magnetic "hole" in active the region and the second mo del is the propagation of radio waves through a layer with zero magnetic field. References Peterova N.G., Akhmedov S.B.: Soviet Astronomy, 1974, 17, 168. Piddington J. H., Minnnett H. C.: Austral. J. Sci. Res., 1951 A4, 131. Tokhchukova S. Bogo d V.: Solar Physics., 2002, 212, 99.