Improving inverse Compton by removing non-linearities

Abstract

We present a new, more nuanced understanding of non-linear effects in inverse Compton sources. Contrary to what has been heretofore understood, deleterious non-linear effects can arise even at low laser intensities, a regime previously viewed as linear. After laying out a comprehensive survey of all non-linear phenomena which degrade the effectiveness of inverse Compton sources, we discuss two powerful techniques designed to remove these non-linearities. Starting with the known technique of longitudinal chirping of the laser pulse, which we developed earlier to mitigate adverse non-linear effects in the high laser field regime, we have discovered that the simple stretching of the laser pulse, while keeping the energy constant, can significantly increase the spectral density of the scattered radiation in many operating regimes. Our numerical simulations show that combining these two techniques removes detrimental non-linearities and improves the performance of inverse Compton sources over an order of magnitude.