APS » PROLA » Phys. Rev. Lett. » Volume 83 » Issue 22
< Previous article | Next article >

Phys. Rev. Lett. 83, 4662 - 4665 (1999)

Power Laws in Solar Flares: Self-Organized Criticality or Turbulence?

Download: PDF (70 kB) or Buy this Article (Use Article Pack) Export: BibTeX or EndNote (RIS)

Guido Boffetta1,1b, Vincenzo Carbone2, Paolo Giuliani2, Pierluigi Veltri2, and Angelo Vulpiani3
1aDipartimento di Fisica Generale and Istituto Nazionale di Fisica della Materia, Universitá di Torino, Via Pietro Giuria 1, 10125 Torino, Italy,
1band Istituto di Cosmogeofisica-CNR, Corso Fiume 4, 10133 Torino, Italy
2Dipartimento di Fisica and Istituto Nazionale di Fisica della Materia, Universitá della Calabria, 87036 Roges di Rende, Italy
3Dipartimento di Fisica and Istituto Nazionale di Fisica della Materia, Universitá “La Sapienza,” Piazzale A. Moro 2, 00185 Roma, Italy

Received 30 March 1999

The statistics of quiescent times τL between successive bursts of solar flares activity, performed using 20 years of data, displays a power law distribution with exponent α≃2.4. This is an indication of an underlying complex dynamics with long correlation times. The observed scaling behavior is in contradiction with the self-organized criticality models of solar flares which predict Poisson-like statistics. Chaotic models, including the destabilization of the laminar phases and subsequent restabilization due to nonlinear dynamics, are able to reproduce the power law for the quiescent times. A shell model of MHD turbulence correctly reproduces all the observed distributions.


©1999 The American Physical Society

URL: http://link.aps.org/doi/10.1103/PhysRevLett.83.4662
DOI: 10.1103/PhysRevLett.83.4662
PACS: 05.65.+b, 47.27.Eq, 47.52.+j, 96.60.Rd

[ Abstract  |  Previous article  |  Next article  |  Issue 22 ]