Our group at Raman Research Institute, Bangalore works on cosmic rays (Galactic and extragalactic), multi-wavelength modelling of AGN and neutrino astronomy. In this talk I select two topics from our current research activities. In the first part of my talk I will discuss about physics of extended jets of quasars.
The radio, optical and X-ray emission from extended jets is difficult to explain with the popular inverse Compton emission model. I will discuss about the other possible scenarios.
In the second part I will discuss about injection, propagation and composition of ultrahigh energy cosmic rays with Pierre Auger data. We have used the publicly available code CRPropa3 to infer some favourable scenarios of source distribution, spectral index of injected cosmic rays and their composition for the EBL model by Dominguez et al.