AbstractIn this study we explore physical scaling laws applied to solar nanoflares, microflares, and large flares, as well as to stellar giant flares. Solar flare phenomena exhibit a fractal volume scaling, V(L)≲L1.9, with L being the flare loop length scale, which explains the observed correlation EM p T p 4 between the total emission measure EMp and flare peak temperature Tp in both solar and stellar flares. However, the detected stellar flares have higher emission measures EMp than solar flares at the same flare peak temperature Tp, which can be explained by a higher electron density that is caused by shorter heating scale height ratios sH/L≈0.04–0.1. Using these scaling laws we calculate the total radiated flare energies EX and thermal flare energies ET and find that the total counts C are a good proxy for both parameters. Comparing the energies of solar and stellar flares we find that even the smallest observed stellar flares exceed the largest solar flares, and thus their observed frequency distributions are hypothetically affected by an upper cutoff caused by the maximum active region size limit. The powerlaw slopes fitted near the upper cutoff can then not reliably be extrapolated to the microflare regime to evaluate their contribution to coronal heating.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    From solar nanoflares to stellar giant flares: Scaling laws and non-implications for coronal heating


    Contributors:

    Published in:

    Advances in Space Research ; 39 , 12 ; 1867-1875


    Publication date :

    2007-03-21


    Size :

    9 pages




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English





    Network Flares as Agents of Coronal Heating

    Pres, P. / Phillips, K. J. H. / Falewicz, R. et al. | British Library Conference Proceedings | 2002


    Modeling solar and stellar flares

    Reale, F. | Elsevier | 2003


    Modeling Solar and Stellar Flares

    Reale, F. / Committee on Space Research (COSPAR) | British Library Conference Proceedings | 2003


    Observational Evidence for Nanoflares

    Winebarger, Amy | NTRS | 2016