JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
TY - CONF AU - Dooling, J.C. AU - Brill, A.R. AU - Kuklev, N. AU - Lobach, I. AU - Lumpkin, A.H. AU - Sereno, N. AU - Sun, Y. ED - Schaa, Volker R.W. ED - Batten, Tonia ED - Bree, Michael ED - Petit-Jean-Genaz, Christine ED - Hunter, Darren TI - Microbunching of Thermionic Cathode RF Gun Beams in the Advanced Photon Source S-Band Linac J2 - Proc. of IBIC2023, Saskatoon, Canada, 10-14 September 2023 CY - Saskatoon, Canada T2 - International Beam Instrumentation Conference T3 - 12 LA - english AB - We report on measurements of beams from thermionic cathode (TC) rf guns in the Advanced Photon Source S-Band Linac. These measurements include the macropulse out of both new and existing TC guns as well as the observation of microbunching within the micropulses of these beams. A gun chopper limits the macropulse FWHM duration to the 10-ns range. Our objectives were to analyse the new TC gun and investigate microbunching within a TC-rf-gun-generated beam. Our diagnostics elucidated longitudinal beam structures from the ns to the fs time scales. Coherent transition radiation (CTR) interferometers responding to far-infrared wavelengths were employed after each compression stage to provide the autocorrelations of the sub-ps micropulse durations. The first compression stage is an alpha magnet and the second a chicane. A CCD camera was used to image the beam via optical transition radiation from an Al screen at the end of the linac and also employed to measure coherent optical transition radiation (COTR) in the visible range. The COTR diagnostic observations, implying microbunching on a fs time scale, are presented and compared with a longitudinal space-charge impedance model. PB - JACoW Publishing CP - Geneva, Switzerland SP - 240 EP - 244 KW - gun KW - linac KW - bunching KW - electron KW - radiation DA - 2023/12 PY - 2023 SN - 2673-5350 SN - 978-3-95450-236-3 DO - doi:10.18429/JACoW-IBIC2023-TUP027 UR - https://jacow.org/ibic2023/papers/tup027.pdf ER -