Integrated system modeling analysis of a cryogenic multi-cell deflecting-mode cavity resonator

A deflecting mode cavity is the integral element for six-dimensional phase-space beam control in bunch compressors and emittance transformers at high energy beam test facilities. RF performance of a high-Q device is, however, highly sensitive to operational conditions, in particular in a cryo-cooling environment. Using analytic calculations and RF simulations, we examined cavity parameters and deflecting characteristics of TM110,π mode of a 5 cell resonator in a liquid nitrogen cryostat, which has long been used at the Fermilab A0 Photoinjector (A0PI). The sensitivity analysis indicated that the cavity could lose 30%–40% of deflecting force due to defective input power coupling accompanying non-uniform field distribution across the cells with 40 ∼ 50 MeV electron beam and 70–80 kW klystron power. Vacuum-cryomodules of the 5 cell cavity are planned to be installed at the Fermilab Advanced Superconducting Test Accelerator facility. Comprehensive modeling analysis integrated with multi-physics simulation too...

[1]  H. Edwards,et al.  First observation of the exchange of transverse and longitudinal emittances. , 2011, Physical review letters.

[2]  J. Ruan,et al.  Tunable subpicosecond electron-bunch-train generation using a transverse-to-longitudinal phase-space exchange technique. , 2010, Physical review letters.

[3]  J. B. Rosenzweig,et al.  Longitudinal phase space characterization of the blow-out regime of rf photoinjector operation , 2009 .

[4]  T. Koeth.  An Observation of a Transverse to Longitudinal Emittance Exchange at the Fermilab A0 Photoinjector , 2009 .

[5]  D. Alesini.  RF DEFLECTOR BASED SUB-PS BEAM DIAGNOSTICS: APPLICATION TO FEL AND ADVANCED ACCELERATORS , 2007 .

[6]  D. Edwards,et al.  A copper 3.9 GHz TM110 cavity for emittance exchange , 2007, 2007 IEEE Particle Accelerator Conference (PAC).

[7]  Zhirong Huang,et al.  Transverse-to-longitudinal emittance exchange to improve performance of high-gain free-electron lasers. , 2006 .

[8]  K. Kim,et al.  Photoinjector generation of a flat electron beam with transverse emittance ratio of 100 , 2005, physics/0511011.

[9]  S. Lidia,et al.  Generation of angular-momentum-dominated electron beams from a photoinjector , 2004, physics/0411063.

[10]  G. Krafft,et al.  Longitudinal Phase Space Manipulation in Energy Recovering Linac-Driven Free-Electron Lasers , 2002, physics/0211048.

[11]  Max Cornacchia,et al.  Transverse to longitudinal emittance exchange , 2002 .

[12]  P. Krejcik,et al.  A transverse rf deflecting structure for bunch length and phase space diagnostics , 2001, PACS2001. Proceedings of the 2001 Particle Accelerator Conference (Cat. No.01CH37268).

[13]  D. Edwards.  An rf separated kaon beam from the Main Injector: Superconducting aspects , 1998 .

[14]  J. Welch,et al.  B-factory optics and beam-beam interaction for millimeter beta and locally shortened bunches , 1991, Conference Record of the 1991 IEEE Particle Accelerator Conference.