A commonly used assumption in interpretation of astrophysical spectra is that of Maxwellian distribution of particle energies. However, this assumption could be incorrect if the emitting system involves long-range or long-term interactions, or dynamic heating (e.g., Collier 2004, Leubner 2004, 2005, 2008). In the solar plasma, departures from Maxwellian distribution can occur at low plasma densities with strong gradient of plasma parameters or in the impulsive phase of solar flares. Moreover, a possible signature of dynamic heating in the solar corona should be a presence of non-Maxwellian distributions.
This proposal focuses on detection of the -distributions characterized by an asymptotically power-law high-energy tail. These distributions have been diagnosed in the Si III SUMER spectra of the transition region (Dzifcakova & Kulinova 2011), they provide better fit for the EIS line profiles (Lee et al. 2012), and are also observed in the solar wind (e.g. Maksimovic et al. 1997, Zouganelis 2008). We propose to use the diagnostic methods developed by Dzifcakova & Kulinova (2010) and Mackovjak et al. (2013), specifically designed for lines observed by the Hinode/EIS instrument. The selected lines involve line ratios that allow simultaneous determination of electron density, temperature and the value of . |
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