ABSTRACT
This chapter describes one of the most important phenomena that governs the behavior of accelerators, namely synchrotron radiation (SR). SR can be both helpful, as it yields the creation of high brightness radiation sources, and harmful, as it can deteriorate the beam by creating additional energy spread and beam emittance growth. The chapter presents simplified back-of-the-envelope style derivations, which nevertheless obtain all of the important characteristics of SR with high accuracy. The SR-induced cooling of the beam emittance and SR-induced emittance growth would naturally balance, so that the beam emittance would eventually reach equilibrium value. Performance of SR-based light sources depends on spatial and spectral characteristics of SR. Though the quantum SR is unlikely to occur in radiation from bends, it can happen in SR during beam collisions, as beams focused to tiny spots can produce enormous fields that cause the oncoming particles to radiate in a quantum regime.
