Saturation of Nonthermal Hard X‐Ray Emission in Solar Flares

• DOI: 10.1086/520331
• Publication Date: 2007-08-31T19:39:45Z
• Authors: David Alexander; Antoun G. Daou
• Keywords: Flare; Solar flare; Saturation (graph theory)

We consider a number of flares spanning range magnitudes over two decades in GOES soft X-ray luminosity and demonstrate an observational confirmation the saturation nonthermal hard photon flux large solar flares. Using unprecedented spectral spatial resolution RHESSI telescope, we find that integrated above 20 keV asymptotically approaches limiting value with increasing flare intensity, suggesting production for high electron-beam fluxes This result is strengthened by considering each as aggregation multiple fiducial energy release events identified using RHESSI. argue sets transition from Coulomb collisions to return current ohmic dissipation dominating losses increase.