On the origin of Mega Radiohalos

We present a first attempt to investigate the origin of radio emitting electrons in the newly discovered class of Mega Radiohalos in clusters of galaxies. We study the evolution of relativistic electrons accreted by the external regions of a simulated cluster of galaxy at high resolution, including the effect of radiative losses and turbulent re-acceleration acting on relativistic electrons. We conclude that turbulent re-acceleration is enough prolonged in time to produce a large reservoir of radio emitting electrons in the large regions illuminated by Mega Radiohalos observed by LOFAR.Comment: 6 pages, 4 figures, submitted to A&A Letter

Exploring the origins of mega radio halos

We present a first attempt to investigate the origin of radio-emitting electrons in the newly discovered class of mega radio halos in clusters of galaxies. We study the evolution of relativistic electrons accreted by the external regions of a simulated cluster of galaxies at high resolution, including the e ffect of radiative losses and turbulent reacceleration acting on relativistic electrons. We conclude that turbulent reacceleration induced by structure formation, if sufficiently prolonged, has the potential to produce a large reservoir of radio-emitting electrons in the large regions illuminated by mega radio halos observed by LOFAR