Single shot transverse emittance measurement from OTR screens in a drift transport section

Abstract

Single shot transverse emittance measurement is essential to assess the beam quality and performance of new generation light sources such as linac based X-ray Free Electron Lasers (FELs) or laser plasma wakefield accelerators (LPWA). To this end, we have developed a single shot transverse emittance measurement using at least 3 screens inserted in the beam at the same time, measuring the beam size at different positions in a drift space in one single shot. In this paper, we firstly present the theoretical aspects to perform the measurement.We secondly show experimental results obtained at Diamond for a 3 GeV electron beam in the transfer line from the Booster to the Storage Ring, using this thin OTR screens method.Finally, we discuss the results showing the strength of the measurement in comparison with more standard and established emittance measurement, like the quadrupole scan method.