Indian Particle Accelerator Conference, Nov 19-22, 2013, VECC, Kolkata InPAC-2013-IT-14 BEAM BASED CHARACTERIZATION OF PHASE SPACE AND TRANSPORT AT TRIUMF VECC TEST FACILITY* Y. Chao † , J. Abernathy, S. Dechoudhury, D. Dutta, C. Gong, A. Laxdal, R. Laxdal, S. Saminathan, A. Vrielink, TRIUMF and VECC Abstract The VECC Test Facility at TRIUMF is a joint project with VECC of Kolkata, India as a demonstration for the front end (300 keV gun and 10 MeV SRF injection complex) of the Electron Linac project. Commissioning has started since 2011 in stages. A program to completely characterize the 6D beam phase space and machine transport of the entire VECC was conceived, developed and is currently being carried out, with the aim of establishing a working machine model on which to base all diagnostic and control procedures, and debugging and refining the process itself. The electron beam itself is used as the main probe in all measurements. Methods and results will be presented. Also presented will be a technique recently developed at the VECC test facility to obtain immediate and detailed information on beam distribution in the longitudinal phase space, and to provide a direct means for diagnosing machine transport. The technique depends on the ability to form direct images of the thermionic gun grid on various view screens through adjusting intervening optics. In the VECC spectrometer equipped with a RF deflecting cavity, this made possible the characterization of the longitudinal phase space of the beam with minimal contamination from transverse planes. Measurement outcome and potential for further experiments will be presented. COMMISSIONING OF TRIUMF VECC TEST FACILITY The VECC Test Facility is currently being commissioned at TRIUMF. This is a culmination of collaborative efforts between members of TRIUMF and VECC over the past 5 years, from inception to producing beam based measurements. Following phase one implementation of the 100 keV thermionic gun and the first half of the low energy transport section (VLBT), commissioning of the gun, beam transport system, RF system, diagnostics and control system started in November 2011, and has gone through subsequent phases in step with extension to beam transport and additional hardware. The latter included the second half of VLBT and its spectrometer arm (VLBT1). Currently the 300 keV gun is in its final stage of implementation and testing, to be followed by 300 keV beam commissioning in VLBT/VLBT1, and injection cryo-module (ICM) installation and commissioning is scheduled for early 2014. Table 1 summarizes progress and milestones from 2011 to now. BEAM BASED CHARACTERIZATION Besides commissioning of beam transport, RF, diagnostics and control systems, a program of beam based Table 1: VECC Test Facility Schedule/Milestone Phase / Dates Agenda Accomplished 0 2011/11 100 keV Gun RF modulation Gun Operation 1 2011/12 - 2012/03 Electron beam in (Short) VLBT Procedure/Protocol • User’s guide • Problem reporting and tracking • Test planning and scheduling VLBT transport Diagnostic tested Allison scanner Control system Procedure/Protocol developed High-level diagnostic/control Install 2012/04 - 06 VLBT (Long) extension VLBT1 hardware/software upgrades 2A+2B 2012/06 - 2013/03 VLBT1 Dipole VLBT1 VLBT (Long) Buncher Special diagnostics • RF deflector • Fast Faraday cup • Dedicated BLM • View screen • RF shield pickup Procedure/Protocol Beam phase space measurement Transfer function measurement VLBT operation VLBT1 operation Special controls EPICS integrated • View screen • LLRF (partial) Diagnostic systems Buncher calibrated RF deflector tested Dipole PS upgrade Control system Procedure/Protocol developed High level diagnostic/control 2013/03 – present 300 keV Gun High voltage Gun RF modulation characterization has been vigorously pursued for the following purposes • Obtain empirical machine and beam operation parameters, and cross calibrate with design and simulation • Establish functional machine and beam model, and validate with beam based data • Commission diagnostic and control procedures, and eventually realize as high level applications Figure 1 illustrates the agenda of this program, which aims to measure the transport properties between all key