Design, specifications, and first beam measurements of the compact linear accelerator for research and applications front end

Angal-Kalinin, D. and Bainbridge, A. and Brynes, A.D. and Buckley, R.K. and Buckley, S.R. and Burt, G.C. and Cash, R.J. and Castaneda Cortes, H.M. and Christie, D. and Clarke, J.A. and Clarke, R. and Cowie, L.S. and Corlett, P.A. and Cox, G. and Dumbell, K.D. and Dunning, D.J. and Fell, B.D. and Gleave, K. and Goudket, P. and Goulden, A.R. and Griffiths, S.A. and Hancock, M.D. and Hannah, A. and Hartnett, T. and Heath, P.W. and Henderson, J.R. and Hill, C. and Hindley, P. and Hodgkinson, C. and Hornickel, P. and Jackson, F. and Jones, J.K. and Jones, T.J. and Joshi, N. and King, M. and Kinder, S.H. and Knowles, N.J. and Kockelbergh, H. and Marinov, K. and Mathisen, S.L. and McKenzie, J.W. and Middleman, K.J. and Militsyn, B.L. and Moss, A. and Muratori, B.D. and Noakes, T.C.Q. and Okell, W. and Oates, A. and Pacey, T.H. and Paramanov, V.V. and Roper, M.D. and Saveliev, Y. and Scott, D.J. and Shepherd, B.J.A. and Smith, R.J. and Smith, W. and Snedden, E.W. and Thompson, N.R. and Tollervey, C. and Valizadeh, R. and Vick, A. and Walsh, D.A. and Weston, T. and Wheelhouse, A.E. and Williams, P.H. and Wilson, J.T.G. and Wolski, A. (2020) Design, specifications, and first beam measurements of the compact linear accelerator for research and applications front end. Physical Review Accelerators and Beams, 23 (4): 044801. ISSN 2469-9888

Abstract

The compact linear accelerator for research and applications (CLARA) is an ultrabright electron beam test facility being developed at STFC Daresbury Laboratory. The ultimate aim of CLARA is to test advanced free electron laser (FEL) schemes that can later be implemented on existing and future short-wavelength FELs. In addition, CLARA is a unique facility to provide a high-quality electron beam to test novel concepts and ideas in a wide range of disciplines and to function as a technology demonstrator for a future United Kingdom x-ray FEL facility. CLARA is being built in three phases; the first phase, or front end (FE), comprises an S-band rf photoinjector, a linac, and an S-bend merging with the existing versatile electron linear accelerator beam line; the second phase will complete the acceleration to full beam energy of 250 MeV and also incorporate a separate beam line for use of electrons at 250 MeV; and the third phase will include the FEL section. The CLARA FE was commissioned during 2018, and the facility was later made available for user experiments. Significant advancements have been made in developing high-level software and a simulation framework for start-to-end simulations. The high-level software has been successfully used for unmanned rf conditioning and for characterization of the electron beam. This paper describes the design of the CLARA FE, performance of technical systems, high-level software developments, preliminary results of measured beam parameters, and plans for improvements and upgrades. © 2020 authors. Published by the American Physical Society.