1. 1 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste The XbFEL Project (X-band technology for FELs) G. D’Auria (Elettra – Sincrotrone Trieste) On behalf of the XbFEL collaboration

2. 2 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste Outline  Short overview of the XbFEL Project The XbFEL Collaboration Motivations for using X-band technology Objectives Concept and approach RF module  Present activities  Future plans  Concluding remarks

3. 3 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste The X-band technology for FELs (XbFEL) is a project submitted for EU funding in September 2014 to HORIZON2020 - Work Programme 2014 – 2015 Research & Innovation Action (RIA) INFRADEV-1-2014 Design Studies The specific challenge and the aim of this activity is: “to support the conceptual and technical design and preparatory actions for New Research Infrastructures, or Major upgrades of Existing Infrastructures” The XbFEL Project ~ 5-6 proposals funded Call numbers:

4. 4 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste The evaluation process has been based on the three main sections of the proposal: Excellence, Impact and Implementation, with the score in the range 0-5. We got: Excellence → 4 (very good) Impact → 4 (very good) Implementation → 5 (excellent) Given the budgetary resources available under the call Not enough to be funded ! Evaluation process 13 in total

5. 5 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste STElettra - Sincrotrone Trieste, Italy. CERNCERN Geneva, Switzerland. JUJagiellonian University, Krakow, Poland. STFCDaresbury Laboratory Cockcroft Institute, Daresbury, UK SINAPShangai Institute of Applied Physics, Shanghai, China. VDL VDL ETG T&D B.V., Eindhoven, Netherlands. OSLOUniversity of Oslo, Norway. IASANational Technical University of Athens, Greece. UUUppsala University, Uppsala, Sweden. ASLSAustralian Synchrotron, Clayton, Australia. UA-IATInstitute of Accelerator Technologies, Ankara, Turkey. ULANC Lancaster University, Lancaster, UK. XbFEL is a collaboration among several laboratories aimed at promoting the development of X-band technology for FEL based photon sources. XbFEL Collaboration

6. 6 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste  The X-band technology has demonstrated the possibility to operate at gradients higher than 100 MV/m with an Ea > 100 MV/m and a BDR/m < 3 x 10-7.  This has multiple advantages for the FEL users community: very compact Normal Conducting Linacs, significantly cheaper than superconducting machines higher efficiency costs reduction possibility to go to a high repetition rate (up to kHz regime). Why X-band technology

7. 7 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste  FERMI FEL Elettra – Sincrotrone Trieste Linac energy increase → FEL shorter wavelenghts (≤ 1 nm) Possibility to operate with two linacs at the same time (two e-beam pulses at different energies)  Ankara University (Turkish X-ray FEL) 6 GeV linac → FEL wavelengths 0.1-10 nm Possibility to operate at high rep rate (up to 500 Hz)  Australian Synchrotron (AXXS–Australian X-band X-ray Source) Plans for a 6 GeV linac  SINAP Shangai Proposal for hard X-FEL (6.5 GeV) submitted to Chinese government.  STFC CLARA FEL Test Facility (Ultra short pulse generation). An S-band linac module (Linac 4) will be replaced with an X-band module as test bed for this technology on FELs.  CERN CERN has no direct interest in Synchrotron Light Sources and FELs, but the activities on XbFEL will have strong return value for the CERN CLIC project: i.e. accelerator and RF components optimization, further technical developments with industry, costs reduction, etc. Interests for X-band FELs_I

8. 8 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste A long-term interest also exists for:  Jagiellonian University_Polish Synchrotron Light Source SOLARIS Solaris linac energy increase 600 MeV → 1.5 GeV, allowing full energy injection without any additional costly civil engineering. Long-term development of a compact VUV - Soft X-ray HGHG.  Oslo University The possibility for a compact FEL based on X-band technology has been presented to the Norwegian light source user community. Several scientists have shown interest for a National Facility.  Uppsala University  National Technical University of Athens  Lancaster University Interest for X-band FELs_II

9. 9 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste  The demand for new FEL facilities is worldwide continuously increasing, spurring plans for new dedicated machines. This led to a general reconsideration of costs and spatial issues, particularly for the hard X-ray sources, driven by long and expensive multi-GeV NC linacs.  For these machines the use of X-band technology can greatly reduce cost and capital investment, reducing the linac length and the size of buildings, opening the way to the construction of a multitude of affordable “Regional Facilities”. Interest for X-band FELs_III

10. 10 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste FERMI Upgrading scheme 12 1.5 GeV 4-80 nm 3.5 GeV < 1 nm S-band linac two e-bunches/RF pulse HF bunch separator Two separate linacs at 50 Hz S-band → 1.5 GeV X-band → 3.5 GeV

11. 11 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste The XbFEL project intend to validate the use of the X- band technology for the construction of the future FEL based photon sources. This will be pursued designing, assembling and testing an X-band accelerating module that can be used as a baseline element for new FEL facilities or the upgrading of existing ones. XbFEL objectives N.B. For the technology development and dissemination of the results, the project will be carried out in close collaboration with industry (VDL), member of the consortium.

12. 12 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste XbFEL_Concept and approach To reach the XbFEL objective, three different FEL schemes will be considered: 1.a green field hard X-ray FEL 2.a green field soft X-ray FEL 3.an upgrade of an existing FEL facility With the specific goals to: a.Develop CDRs for the three different scenarios mentioned above b.Identify and develop a common RF unit for the linacs (RF accel. struct., components, etc.) c.Build and test prototypes of the key components. d.Promote the capability of industry to provide such components.

13. 13 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste RF phase advance 2π/33π/4 a/lambda0.145 d/h0.13130.1 Pt401 MW Ls1 m # klystrons10 # structures10 x 4 = 40 a3.62 mm d1.09 mm0.937 mm vg/c3.75 %3.29% tp90 ns102 ns Qe1800019000 Constant Impedance Accelerating Structure with input power coupler only A. Grudiev, HG2013 workshop X-band module layout P C RF load Klystron Pulse compressor Hybrid HV Modulator

14. 14 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste Present activities At present the Collaboration activity is focused on a bi-weekly Web meeting, “the X-band FEL parameters meeting”, organized by D. Schulte, A. Latina and myself, where relevant topics on X- band FEL developments are presented and discussed. Recent issues (Dec. 18, 2014): Bunch Compression Schemes for X-band FELs, T. Charles, Australian Synchrotron- Monash University Sensitivity studies for X-band FEL design, Tasos Charitonidis (NTUA) Planned Oslo work in the XbFEL collaboration, Erik Adli, Oslo University Recently we have also discussed about the possibility to use the CALIFES linac for X-band FEL beam studies and developments.

15. 15 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste 430 kV modulator 50 MW Klystron RF Pulse compressor LLRF Vacuum controller s Future plans I The road map is already defined and, after the signature of the EU Grant Agreement (May – June 2015), the project will start with the activities already planned in the XbFEL workplan (July 2015 - June 2018). Two possible scenarios for the near future: a) The project is funded X N o t f u n d e d

16. 16 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste 430 kV modulator RF Pulse compressor LLRF Vacuum controller s Future plans II b) The project is not funded It would be extremely important to keep the XbFEL collaboration “alive” and the working group on the X-band technology development for FEL active. Continue the periodic Web meetings, to strengthen the collaboration, fostering further developments of X-band technology. Define a reduced work program (i.e. extracted from the workplan already submitted to EU). Organize dedicated meetings/workshops, (may be twice per year, one during the annual CLIC workshop, the other one in June/July), to define and check the strategic guidelines. Continue to work on the X-band module development identifying a baseline solution for FEL applications (accel. struct., RF components, etc). Evaluate new funding possibilities and opportunities.

17. 17 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste  Linac design based on FEL users requirements (i.e. wavelength range, energy per pulse, pulse duration, pulse structure, etc.).  Beam dynamics studies, bunch compressors, deflecting cavities, bunch spreaders.  Timing and synchronization schemes.  Identify and develop a common hardware solutions for the accelerating unit.  Component fabrication  RF module assembly and high power tests Main topics for future activities If possible

18. 18 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste  The XbFEL project strongly promote the use of the X-band technology for the future FEL based photon sources.  This would allow the construction of these facilities with a technological solution that is more efficient in terms of costs, space and power than the conventional ones.  The activities on the XbFEL will also have a strong return value for the CERN CLIC project. Concluding remarks It is extremely important to maintain the XbFEL Collaboration active regardless of the EU funding!

19. 19 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste Acknowledgements My special thanks to the whole XbFEL Collaboration. In particular: L. Giannessi, M. Kiskinova, C. Masciovecchio, A. Santelli, Elettra-Sincrotrone Trieste A. Latina, D. Schulte, S. Stapnes, W. Wuensch, CERN, Geneva C. Bocchetta, Jagiellonian University, Krakow J. Clarke, Daresbury Laboratory Cockcroft Institute, Daresbury W. Fang, Shangai Institute of Applied Physics, Shanghai X.J.A. Janssen VDL ETG T&D B.V., Eindhoven E. Adli, University of Oslo E. N. Gazis, National Technical University of Athens M. Jacewicz, R. Ruber, Uppsala University, Uppsala M. J. Boland, Australian Synchrotron, Clayton A. Aksoy, Ö. Yavaş, Institute of Accelerator Technologies, Ankara, Turkey. G. Burt, Lancaster University, Lancaster

20. 20 CLIC Workshop 2015, 26 – 30 January 2015 Gerardo D’Auria_Elettra-Sincrotrone Trieste HG2015 The 8 th International Workshop on High-Gradient Acceleration HG2015 this year will be hosted by Tsinghua University June 16-19, 2015