Optimizations of transverse projected emittance at the photo-injector test facility at DESY, location Zeuthen

Autor: Grygorii Vashchenko, G. Klemz, Juliane Rönsch-Schulenburg, Sascha Schnepp, Mikhail Krasilnikov, Ingo Will, M. Hänel, Brendan O'Shea, Daniele Sertore, H.-J. Grabosch, L. Staykov, Erion Gjonaj, M. Nozdrin, J. Bähr, M. Otevrel, Frank Stephan, Laura Monaco, Sven Lederer, L. Hakobyan, M. Mahgoub, Siegfried Schreiber, Paolo Michelato, Martin Khojoyan, A. Shapovalov, G. Asova, Y. Ivanisenko, Bagrat Petrosyan, Thomas Weiland, Wolfgang Ackermann, Sakhorn Rimjaem, Roman Spesyvtsev, D. Richter
Jazyk: angličtina
Rok vydání: 2012
Předmět:
Zdroj: Nuclear instruments & methods in physics research / A 671, 62-75 (2012). doi:10.1016/j.nima.2011.12.101
Popis: High brightness electron sources for linac based short-wavelength free-electron lasers are developed and optimized for small transverse projected emittance at the photo-injector test facility at DESY, location Zeuthen (PITZ). A major part of the measurement program at PITZ is dedicated to transverse phase space optimization in order to fulfill the requirements of the European X-ray free-electron laser (European XFEL). A laser-driven RF-gun, treated with a dry-ice sublimation-impulse cleaning technique, a new photocathode laser system allowing short rise and fall times of the flat-top temporal distribution as well as several new diagnostic components have been installed at PITZ in 2008. The electrons generated via the photo-effect at a cesium telluride (Cs2Te) cathode are accelerated by a 1.6 cell L-band RF-gun cavity with a maximum accelerating gradient at the cathode of about 60 MV/m. The transverse projected emittance is measured using a single slit scan technique. In the 2008–2009 run period, a detailed characterization of the projected transverse emittance was performed at different operating conditions. Optimizations and measurement results as well as simulation predictions of the transverse projected emittance for bunch charges of 1, 0.5, 0.25 and 0.1 nC are presented and discussed in this paper. The geometric mean of the normalized projected rms emittance in both transverse directions for an electron bunch charge of 1 nC was measured to be
Databáze: OpenAIRE