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Design of a 162.5 MHz continuous-wave normal-conducting radiofrequency electron gun

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Abstract

A high-gradient radiofrequency (RF) gun operated in continuous-wave (CW) mode is required in various accelerating applications. Due to the high RF power loss, a traditional normal-conducting (NC) RF electron gun has difficulty meeting the requirement of generating a high-repetition-rate electron beam. The development of a scheme for a CW NC-RF gun is urgently required. Demonstrated as a photoinjector of a high-repetition-rate free-electron laser (FEL), an electron gun operated in CW mode and the VHF band is designed. An analysis of the reentrant gun cavity is presented in this paper to increase the gradient and decrease the power density and power dissipation. Referring to the analysis results, the design of a 162.5 MHz gun cavity is optimized by a multi-objective evolutionary algorithm to achieve better performance in CW mode. Multipacting and thermal analyses are also deliberated in the design to coordinate with RF and mechanical design. The optimized 162.5 MHz gun cavity can be operated in CW mode to generate a high-repetition-rate beam with voltage up to 1 MV and gradient up to 32.75 MV/m at the cathode.

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References

  1. M.P. Minitti, J.M. Budarz, A. Kirrander et al., Imaging molecular motion: femtosecond x-ray scattering of an electrocyclic chemical reaction. Phys. Rev. Lett. 114, 255501 (2015). https://doi.org/10.1103/PhysRevLett.114.255501

    Article  MathSciNet  Google Scholar 

  2. C. Feng, H.X. Deng, Review of fully coherent free-electron lasers. Nucl. Sci. Tech. 29, 160 (2018). https://doi.org/10.1007/s41365-018-0490-1

    Article  Google Scholar 

  3. Z.T. Zhao, C. Feng, K.Q. Zhang, Two-stage EEHG for coherent hard X-ray generation based on a superconducting linac. Nucl. Sci. Tech. 28, 117 (2017). https://doi.org/10.1007/s41365-017-0258-z

    Article  Google Scholar 

  4. D.H. Dowell, E. Jongewaard, J. Lewandowski et al., The development of the linac coherent light source RF Gun. ICFA Beam Dyn. Newslett. 46, 162–192 (2008)

    Google Scholar 

  5. R. Rimmer, N. Hartman, S. Lidia et al. High-gradient high-duty-factor rf photo-cathode electron gun. NASA STI/Recon Technical Report N

  6. C.J. Tan, C.X. Tang, W.H. Huang et al., Beam and image experiment of beam deflection electron gun for distributed X-ray sources. Nucl. Sci. Tech. 30, 50 (2019). https://doi.org/10.1007/s41365-019-0561-y

    Article  Google Scholar 

  7. X. Li, J.Q. Zhang, G.Q. Lin et al., Performance of an electron linear accelerator for the first photoneutron source in China. Nucl. Sci. Tech. 30, 53 (2019). https://doi.org/10.1007/s41365-019-0576-4

    Article  Google Scholar 

  8. Z. Wang, C. Feng, Q. Gu et al., Generation of double pulses at the shanghai soft X-ray free electron laser facility. Nucl. Sci. Tech. 28, 28 (2017). https://doi.org/10.1007/s41365-017-0188-9

    Article  Google Scholar 

  9. H.P. Geng, J.H. Chen, Z.T. Zhao, Scheme for generating 1 nm X-ray beams carrying orbital angular momentum at the SXFEL. Nucl. Sci. Tech. 31, 88 (2020). https://doi.org/10.1007/s41365-020-00794-7

    Article  Google Scholar 

  10. Y.Y. Xia, Z.T. Zhao, Y.B. Zhao et al., Transfer function measurement for the SSRF SRF system. Nucl. Sci. Tech. 30, 101 (2019). https://doi.org/10.1007/s41365-019-0612-4

    Article  Google Scholar 

  11. C.H. Miao, M. Liu, C.X. Yin et al., Precise magnetic field control of the scanning magnets for the aptron beam delivery system. Nucl. Sci. Tech. 28, 172 (2017). https://doi.org/10.1007/s41365-017-0324-6

    Article  Google Scholar 

  12. B.C. Jiang, G.Q. Lin, B.L. Wang et al., Multi-bunch injection for SSRF storage ring. Nucl. Sci. Tech. 26, 050101 (2015). https://doi.org/10.13538/j.1001-8042/nst.26.050101

    Article  Google Scholar 

  13. T. Phimsen, B.C. Jiang, H.T. Hou et al., Improving Touschek lifetime and synchrotron frequency spread by passive harmonic cavity in the storage ring of SSRF. Nucl. Sci. Tech. 28, 108 (2017). https://doi.org/10.1007/s41365-017-0259-y

    Article  Google Scholar 

  14. B. Dunham, J. Barley, A. Bartnik et al., Record high-average current from a high-brightness photoinjector. Appl. Phys. Lett. 102, 034105 (2013). https://doi.org/10.1063/1.4789395

    Article  Google Scholar 

  15. I.V. Bazarov, B.M. Dunham, C.K. Sinclair, Maximum achievable beam brightness from photoinjectors. Phys. Rev. Lett. 102, 104801 (2009). https://doi.org/10.1103/PhysRevLett.102.104801

    Article  Google Scholar 

  16. D. Filippetto, P. Musumeci, M. Zolotorev et al., Maximum current density and beam brightness achievable by laser-driven electron sources. Phys. Rev. ST Accel. Beams 17, 024201 (2014). https://doi.org/10.1103/PhysRevSTAB.17.024201

    Article  Google Scholar 

  17. F. Sannibale, D. Filippetto, C. Papadopoulos et al., Advanced photoinjector experiment photogun commissioning results. Phys. Rev. Spec. Top. Accel. Beams 15, 103501 (2012). https://doi.org/10.1103/PhysRevSTAB.15.103501

    Article  Google Scholar 

  18. F. Zhou et al., in Proceedings, 10th International Particle Accelerator Conference (IPAC2019): Melbourne, Australia, 19–24 May, 2019, First Commissioning of LCLS-II CW Injector Source. 2019, p. TUPTS106. https://doi.org/10.18429/JACoW-IPAC2019-TUPTS106

  19. T. Luo, H. Feng, D. Filippetto et al., RF design of APEX2 two-cell continuous-wave normal conducting photoelectron gun cavity based on multi-objective genetic algorithm. Nucl. Instrum. Methods Phys. Res. Sect. A Accel. Spectrom. Detect. Assoc. Equip. 940, 12–18 (2019). https://doi.org/10.1016/j.nima.2019.05.079

    Article  Google Scholar 

  20. G. Shu, Y. Chen, S. Lal et al., in Proceedings, 10th International Particle Accelerator Conference (IPAC2019): Melbourne, Australia, 19–24 May, 2019, first design studies of a NC CW RF gun for European XFEL. 2019, p. TUPRB010. https://doi.org/10.18429/JACoW-IPAC2019-TUPRB010

  21. Z. Zhao, D. Wang, Z. Yang et al., in Proceedings of International Free Electron Laser Conference (FEL’17), Santa Fe, NM, USA, August 20-25, 2017, SCLF: An 8-GeV CW SCRF Linac-Based X-Ray FEL Facility in Shanghai. No. 38 in International Free Electron Laser Conference (JACoW, Geneva, Switzerland, 2018), pp. 182–184. https://doi.org/10.18429/JACoW-FEL2017-MOP055

  22. J. Yan, H. Deng, Multi-beam-energy operation for the continuous-wave X-ray free electron laser. Phys. Rev. Accel. Beams 22, 090701 (2019). https://doi.org/10.1103/PhysRevAccelBeams.22.090701

    Article  Google Scholar 

  23. Z. Wang, C. Feng, D.Z. Huang et al., Nonlinear energy chirp compensation with corrugated structures. Nucl. Sci. Tech. 29, 175 (2018). https://doi.org/10.1007/s41365-018-0512-z

    Article  Google Scholar 

  24. J. Schmerge, A. Brachmann, D. Dowell et al., in The LCLS-II Injector Design. Basel, Switzerland, 2014, pp. 815 – 819, accelerating gradient; Continuous waves; Design challenges; High repetition rate; Performance requirements; Repetition rate; Spectral range; Superconducting linear accelerators

  25. M. Kranjčević, A. Adelmann, P. Arbenz et al., Multi-objective shape optimization of radio frequency cavities using an evolutionary algorithm. Nucl. Instrum. Methods Phys. Res. Sect. A Accel. Spectrom. Detect. Assoc. Equip. 920, 106–114 (2019). https://doi.org/10.1016/j.nima.2018.12.066

    Article  Google Scholar 

  26. K. Halbach, R.F. Holsinger, SUPERFISH - a computer program for evaluation of RF cavities with cylindrical symmetry. Part. Accel. 7, 213–222 (1976)

    Google Scholar 

  27. I.V. Bazarov, C.K. Sinclair, Multivariate optimization of a high brightness DC gun photoinjector. Phys. Rev. Spec. Top. Accel. Beams 8, 034202 (2005). https://doi.org/10.1103/PhysRevSTAB.8.034202

    Article  Google Scholar 

  28. R. Bartolini, M. Apollonio, I. Martin, Multiobjective genetic algorithm optimization of the beam dynamics in linac drivers for free electron lasers. Phys. Rev. Spec. Top. Accel. Beams (2012). https://doi.org/10.1103/PhysRevSTAB.15.030701

    Article  Google Scholar 

  29. K. Deb, A. Pratap, S. Agarwal et al., A fast and elitist multiobjective genetic algorithm: NSGA-II. IEEE Trans. Evol. Comput. 6, 182–197 (2002). https://doi.org/10.1109/4235.996017

    Article  Google Scholar 

  30. W. Kilpatrick, Criterion for vacuum sparking designed to include both RF and DC. Rev. Sci. Instrum. 28, 824–826 (1957). https://doi.org/10.1063/1.1715731

    Article  Google Scholar 

  31. J. Yan, H. Deng, Generation of large-bandwidth X-ray free electron laser with evolutionary many-objective optimization algorithm. Phys. Rev. Accel. Beams 22, 020703 (2019). https://doi.org/10.1103/PhysRevAccelBeams.22.020703

    Article  Google Scholar 

  32. Coax components specifications. https://www.shively.com/wp-content/uploads/2018/04/tb-linespecs.pdf

  33. Cst studio suite, cst mircowave studio. https://www.3ds.com/products-services/simulia/products/cst-studio-suite/

  34. K. Liu, L. Li, C. Wang et al., Multi-port cavity model and low-level RF systems design for VHF gun. Nucl. Sci. Tech. 31, 8 (2020). https://doi.org/10.1007/s41365-019-0711-2

    Article  Google Scholar 

  35. S. Lal, Study of the effect of loop inductance on the RF transmission line to cavity coupling coefficient. Rev. Sci. Instrum. 87, 083308 (2016). https://doi.org/10.1063/1.4961578

    Article  Google Scholar 

  36. Z.B. Li, A. Grudiev, W.C. Fang et al., Radio-frequency design of a new c-band variable power splitter. Nucl. Sci. Tech. 30, 100 (2019). https://doi.org/10.1007/s41365-019-0611-5

    Article  Google Scholar 

  37. Y. Liao, S. Wang, H. Guo et al., Design and implementation of wide range and high precision electron gun control system. Nucl. Tech. 42, 020202 (2019). https://doi.org/10.11889/j.0253-3219.2019.hjs.42.020202 (in Chinese)

    Article  Google Scholar 

  38. E. Somersalo, P. Yla-Oijala, D. Proch, in Proceedings Particle Accelerator Conference, Analysis of Multipacting in Coaxial Lines, vol. 3, pp. 1500–1502. IEEE (1995). https://doi.org/10.1109/PAC.1995.505264

  39. Z. Yao, R. Laxdal, V. Zvyagintsev et al., in Multipacting Suppression in a Single Spoke Cavity. THP034, these proceedings

  40. Ansys multiphysics. https://www.ansys.com/products/platform/multiphysicssimulation

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Wang, C., Zhu, ZH., Jiang, ZG. et al. Design of a 162.5 MHz continuous-wave normal-conducting radiofrequency electron gun. NUCL SCI TECH 31, 110 (2020). https://doi.org/10.1007/s41365-020-00817-3

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  • DOI: https://doi.org/10.1007/s41365-020-00817-3

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