A comparative study of non-thermal parameters of the X-class solar flare plasma obtained from cold and warm thick-target models; error estimation by Monte Carlo simulation method

• Published in: Astrophysics and space science 2020, Vol.365 (1), Article 18
• Main Authors: Kumar, Pramod, Choudhary, R. K., Sampathkumaran, P., Mandal, Subhayan
• Format: Article
• Language: English
• Subjects: Astrobiology; Astronomy; Astrophysics; Astrophysics and Astroparticles; Cold; Comparative studies; Computer simulation; Correlation coefficient; Correlation coefficients; Cosmology; Electron transport; Error analysis; Mathematical models; Monte Carlo simulation; Observations and Techniques; Original Article; Parameter estimation; Physics; Physics and Astronomy; Plasma; Solar flares; Space Exploration and Astronautics; Space Sciences (including Extraterrestrial Physics; Standard error; Statistical analysis; Thermal energy; Thermal plasmas; Thermalization (energy absorption); Thermodynamic properties
• ISSN: 0004-640X; 1572-946X
• DOI: 10.1007/s10509-020-3731-9

The electron transport and relaxation in the non-thermal plasma of solar flare are often described by cold thick-target model. Recently introduced warm thick-target model however is also found to be more consistent for describing it and hence provide the accurate estimate of parameters of non-thermal solar flare plasma. In this study, we evaluate the consistency of cold and warm thick-target models by estimating non-thermal parameters viz., low-energy cutoff ( E c / E w c ), kinetic power of non-thermal electrons ( P n t h / P w n t h ) and non-thermal energy ( E n t h / E w n t h ), along with standard error (SE) and their linear statistical analysis with respect to flare duration ( t f ). We further evaluate the accuracy of these parameters using Monte Carlo simulation data in 2 σ limits. We found that cold thick-target model gives high values of mean and SE of the estimated parameters compare to warm thick-target model those were also found consistent with the Monte Carlo data (in both cases). Here, we also found that the variation of E c / E w c and P n t h / P w n t h with respect to t f give a negative/positive and positive values of correlation coefficient ( r ) and slope ( b ) respectively which account for upper and lower limits of E c / E w c and high and slow rate of thermalization of non-thermal electrons. Our results show that the warm thick-target model is more consistent model compare to cold thick-target model that could also lead a multi-temperature component in the thermalized plasma.