Millimeter Observations of the 2013 February 17 Solar Flare

Due to the great complexity of a solar flare, the study of many wavelengths is necessary to understand the physical processes involved. By fitting the radio spectra of solar flares with theoretical models, the evolution of some physical parameters of the flaring source is obtained, such as the magnetic field, electron density, spectral index. The objective of this work is the analysis of the radio spectrum at high frequencies, especially the evolution and energy distribution of the population of accelerated electrons. Here, we present the investigation of the solar flare of February 17, 2013 that occurred at 15:47:10 UT. This event was studied in radio from 5 to 405 GHz, and also in X-rays from RHESSI. The spectrum was fitted by a power law, which provided the peak frequency and spectral indices of optically thin and optically thick regimes. The results yield a spectral hardening in the range of 45 to 405 GHz, and that both the temporal profile and the spectral index are different for the millimeter and microwave emission.