Example of fit to RHESSI spectrum. Top panel: RHESSI photon flux (error bars) registered from the area marked in Fig. 3 during the entire 19:04–19:05 UT peak. Components of the fit used are as follows: thermal continuum (red), thick-target model (violet), and the Fe (6.7 keV) and Ni (8.0 keV) line complexes (orange and green Gaussians, respectively). The sum of the components is presented with the light blue line. Bottom panel: normalised residuals (sigma) for the spectral fit.