Estimations of Local Magnetic Fields in Solar Flares: Basic Methods and Some Results

Abstract

ABSTRACT. We consider three methods for estimations of local magnetic fields in solar flares: (1) analysis of bisectors of I  V profiles (Lozitsky, 2015); (2) search for Zeeman-like effects in cores of spectral lines with very low Lande factors, g eff  0.01 (Lozitsky, 1993(Lozitsky, , 1998; (3) semi-empirical modeling using many spectral lines and two-component models (see, e.g., Lozitsky et al., 2000). We illustrate the application of named methods to different observational data and to different spectral lines. Our main conclusions are following: (a) upper limit of local magnetic fields in solar flares is, at least, 10 4 G, (b) such extremely strong fields can occur in very small, spatially unresolved scales, (c) lifetime of such fields is, at least, a few minutes..