Radio observations by ALMA and upper limits on gamma ray flux by Fermi LAT have ruled out inverse Compton scattering of Cosmic Microwave Background radiation by relativistic electrons (IC/CMB) as the origin of X-ray emission from extended jets of six quasars 3C 273, PKS 0637-752, PKS 1136- 135, PKS 1229-021, PKS 1354+195, and PKS 2209+080. Previously it has been shown that proton synchrotron could be the possible radiative process for X-ray emission from the extended jets of 3C 273 and PKS 0637-752. Here we extend this study to include five other extended jets of quasars S5 2007+777, PKS 1136-135, PKS 1229-021, PKS 1354+195, and PKS 2209+080 to find out whether their X-ray emission could be of proton synchrotron origin.

Each extended jet contains several knots distributed along its length, which are emitting brightly in radio to X-ray frequencies. We model the emission from each knot separately to study whether there are knot to knot variations in the strength of magnetic field, luminosity in relativistic electrons and protons. Please refer to https://arxiv.org/pdf/1811.06422.pdf for a revised two-population modelling of the sources presented here. I am sharing the one population modelling approach here as it is still interesing to study the parameters required to explain the observed data from the knots without using multiple zones. But of course the published version is a more detailed study.