Submission_time: 2013/03/17 03:24 EST

Last_Name:VERMA
First_Name:VIRENDRA
Middle_Name:
Badge_Name:V. K. VERMA
Email_Address:vkvermadr@rediffmail.com

Affiliation:Uttrakhand Space Application Center, Dehradun, india

Working_Group 1st Choice:WG1

Working_Group 2nd Choice:WG2

Title:On the Origin of Coronal Mass Ejections

Abstract:In the present paper we have studied the relationship of coronal mass ejections (CMEs) with solar flares including active prominences and coronal holes. This study is a part of our research work to understand the origin of CMEs and its relationship with other solar phenomena. To carry out this study we have used partial and halo CMEs data for the period 29 April 1996 and 31 December 2012 observed by LASCO/ SOHO and the daily solar CHs maps data observed and CHs synoptic chart prepared at KPNO for the same period. We also used solar activity events data recorded by EIT instruments aboard SOHO, X-ray images of Sun recorded by Yohkoh mission, solar activity events recorded in Hα emission from various ground based-based observatories. To understand the origin of HCMEs, we first matched time of onset of HCMEs with time of solar events in Hα or EIT data. Secondly we looked for the spatial location of solar activity phenomena and CH maps on the solar disk or CHs synoptic chart. The LASCO/ SOHO recorded 909 partial and halo CMEs events during the time interval 1996-2012 and 16 CMEs were excluded because their acceleration are not known accurately. An investigation of 893 partial and halo CME events and related solar flares and coronal holes data we find following:

1-38% HCMEs events were observed when there were CHs within 1-10 degree of solar flares locations,
2-26% HCMEs events were observed when there were CHs within 11-20 degree of solar flares locations,
3-18% HCMEs events were observed when there were CHs within 21-30 degree of solar flares locations,
4-12% HCMEs events were observed when there were CHs within 31-40 degree of solar flares locations, and
5-6% HCMEs events were observed when there were CHs within 41-50 degree of solar flares locations.

From above results we are of the view that the partial and halo CMEs may have been produced by some mechanism, in which the mass ejected by solar flares or active prominences, gets connected with the open magnetic lines of CHs (source of high speed solar wind streams) and moves along them to appear as suggested earlier by Verma and Pande (1989) and Verma (1998).

References:
Verma, V. K. & Pande, M. C. (1989) Proc. IAU Colloq. 104 Solar and Stellar Flares (Poster Papers), Stanford University, Stanford, USA, p.239.

Verma, V. K.(1998) Journal of Geophysical Indian Union, 2, 65.







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