Relationship of CMEs and N-S AR-interconnecting loops observed by SXT and Nobeyama radioheliograph

Sachiko Akiyama

Abstract

We report the relationship between the coronal mass ejection (CME) and the long transequatorial interconnecting loops, which is connecting the north AR 8457 with the south AR 8458. These interconnecting loops were observed during 9--23 February 1999, using SXT/Yohkoh and Nobeyama radioheliograph. At first transequatorial interconnecting loops were observed over the east limb on 9 February 1999 by the SXT/Yohkoh. Finally we could not observe interconnecting loops over the west limb on 23 February 1999 due to solar rotation. The structure of these loops were clearly changed when flare occurred at either connecting AR. Using the C2/LASCO, we could see CME associated with the flare. For the SXT difference image we could also see a loop like dimming. A structures of the dimming is same interconnecting loops observed in previous image of the flare. For that reason we suggested that erupted interconnecting loops were observed as the CME. We estimated that a mass of interconnectingloop was 10^14 g using SXT data.

We investigated same structures observed by other wavelength, then we found interconnecting loop over the limb observed by Nobeyama radioheliograph. These loop could only see over the limb because the radio signal of interconnecting loop was weaker than that of solar disk. Moreover we could not clearly see that radio interconnecting loop vanished when flare occurred. However we examined the time profile of the radio signal of interconnecting loop, and we found that the decrease of the signal was almost simultaneous with the increase of the X-ray. As a consequence we suggested that radio interconnecting loops were also erupted and became the CME. We propose that interconnecting loopsexist over the wide wavelength and are one of source of CME's mass.

Authors: S. Akiyama, K. Hori, H. Nakagima and H. Hara

  Organization: Graduate University for Advanced Studies / NAOJ
     Telephone: +81-42-759-8146
           Fax: +81-42-759-8469
        e-mail: akiyama@flare2.solar.isas.ac.jp
       Address: Yohkoh Data Analyze Center,
   c/o Prof. Y. Ogawara,
   Institute of Space and Astronautical Science
   3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510, Japan