RADIO FLARES FROM THE ACTIVE BINARY-SYSTEM UX ARIETIS

In this paper the flaring activity of the active binary system UX Arie tis is investigated by analysing some radio spectra acquired by the Ef felsberg 100-m radiotelescope. These spectra are characterized by posi tive spectral indexes, and show the evolution of the emission during t he flare rising phases. The usual interpretation in terms of gyrosynch rotron emission from relativistic electrons trapped in a bipolar magne tic field and undergoing collisional and radiative losses does not fit these data. For this reason a continuous injection of accelerated par ticles has been included in the model. The computed spectra evolve in time in agreement with available observations.