Quick search Find article
Quick search
Find article

Different Power-Law Indices in the Frequency Distributions of Flares with and without Coronal Mass Ejections

FREE

S. Yashiro1,2, S. Akiyama1,2, N. Gopalswamy2 and R. A. Howard3

Show affiliations


We investigated the frequency distributions of flares with and without coronal mass ejections (CMEs) as a function of flare parameters (peak flux, fluence, and duration of soft X-ray flares). We used CMEs observed by the Large Angle and Spectrometric Coronagraph (LASCO) on board the Solar and Heliospheric Observatory (SOHO) mission and soft X-ray flares (C3.2 and above) observed by the Geostationary Operational Environmental Satellite (GOES) during 1996-2005. We found that the distributions obey a power law of the form dN/dX vprop X, where X is a flare parameter and dN is the number of events recorded within the interval [X, X + dX]. For the flares with (without) CMEs, we obtained the power-law index α = 1.98 ± 0.05 (α = 2.52 ± 0.03) for the peak flux, α = 1.79 ± 0.05 (α = 2.47 ± 0.11) for the fluence, and α = 2.49 ± 0.11 (α = 3.22 ± 0.15) for the duration. The power-law indices for flares without CMEs are steeper than those for flares with CMEs. The larger power-law index for flares without CMEs supports the possibility that nanoflares contribute to coronal heating.


Subject headings

Sun: corona; Sun: coronal mass ejections (CMEs); Sun: flares


Dates

Issue 2 (2006 October 20)

Received 2006 August 28, accepted for publication 2006 September 5

Published 2006 October 5



Users also read

What's this?
This innovative new feature generates a list of articles 'also read' by other users based on them reading the original article. Article abstracts citations and references are all considered and weighted accordingly. We hope that this will help you find relevant papers for your research.

  1. Spatial Relationship between Solar Flares and Coronal Mass Ejections
  2. RHESSI Microflare Statistics. I. Flare-Finding and Frequency Distributions

View by subject




Export








Please login to access our web services, or create an account if you don't yet have one.

You must have cookies enabled in your web browser to be able to login.

Username
Password

Forgotten your password? Get a new one here.