Non-thermal radiation due to CR transport in the magnetic halo of the Milky Way

; Felix Aharonian 7 ; Hai-Ming Zhang 3 ; Yi Zhang 6 ; Giovanni Stel 1 ; Andrew Strong 6 ; Micheal Yeung 6 ; Andrea Merloni 6 1 INAF - OA Brera 2 INAF - IRA 3 Nanjing University 4 UCLA 5 Radboud University Nijmegen 6 MPE 7 Dublin Institute for Advanced Studies The large-scale structures such as Fermi Bubbles and eROSITA Bubbles provide a unique opportunity to study our Milky Way. However, the nature and origin of these large structures are still under debate. In this talk, I will present the identification of several kpc-scale magnetised structures based on their polarized radio emission and their gamma-ray counterparts, which can be interpreted as the radiation of relativistic electrons in the Galactic magnetic halo. These non-thermal structures extend far above and below the Galactic plane and are spatially coincident with the thermal X-ray emission from the eROSITA Bubbles. Multi-wavelength spectral energy distribution analyses have revealed that both thermal and non-thermal extended structures can be explained by Galactic outflows driven by the active star-forming regions located at 3 − 5 kpc from the Galactic Centre. These results reveal how X-ray-emitting and magnetised halos of spiral galaxies can be related to intense star formation activities.