WP12: Innovative RF Technologies

1. WP12: Innovative RF Technologies Co-ordinators: Peter McIntosh (STFC Daresbury Laboratory) Wolf Dietrich-Moller (DESY) Stephane Chel (CEA) Co-ordinators: Peter McIntosh (STFC Daresbury Laboratory) Wolf Dietrich-Moller (DESY) Juliette Plouin (CEA)

2. WP12 Task Activities Task 12.1 WP12 Management Peter McIntosh (STFC) Task 12.2 SRF Thin Films Claire Antoine (CEA) Task 12.3 High Gradient NC Walter Wuensch (CERN) Task 12.4 SRF HOM Beam Diagnostic Roject Jones (Man. Univ.) Task 12.5 RF Photocathodes Robert Nietubyc (NCBJ)

3. WP12 Milestones Task 12.2 Task 12.3 Task 12.4 Task 12.5

4. WP12 Deliverables Task 12.2 Task 12.3 Task 12.4 Task 12.5

5. Task 12.1 Management • Task Kick-off Meetings: • 12.2 Thin Films at CERN on 14th June. • 12.3 High Gradient NC by telecon on 30th May: • http://indico.cern.ch/conferenceDisplay.py?confId=251925 • 12.4 SRF HOM Diagnostics – same team transition from EUCARD. • 12.5 RF Photocathodes at HZB Berlin on 12th July: • https://espace.cern.ch/eucard2-intranet/WP12/12.5/default.aspx

6. Task 12.2 Thin Films CEA Saclay • The magnetometer + cryostat have been partially refurbished. It can now reach >150 mT, with much better thermal performances. It is now apt to study films deposited onto bulk Nb. Further improvements are foreseen. Latest measurements will be presented at SRF 2013. INP Grenoble • Chemical Vapor Deposition of NbN thin films (50  nm  to 500 nm) on sapphire substrates and on AlN/sapphire stacks has started • Optimization of the process conditions (deposition temperature, gaseous flow rates) to obtain the cubic superconductive phase is under way. At HZB Berlin • Postdoc hired for simulation of quadrupole resonator, manufacture and experiments with thin films • Postdoc will present simulation results at SRF13 • Started procurement process of resonator, Niowave is manufacturer, delivery will be October 2013 • Started procurement of vertical test stand (not covered by EuCARD2, but required for the experiments), delivery in 2013 CERN • Collaboration with Sheffield University (not funded through EUCARD-2) initiated for the analysis of first HIPIMS samples.

7. Task 12.3 High Gradient NC CERN Co-organized HG2013 http://indico.cern.ch/conferenceDisplay.py?confId=231116 at which many task members were able to meet. Organizing Task 12.3 meeting to be held during the next CLIC workshop 3-7 February 14. Lancaster University and STFC: Interviews for PDRA position made, offer made but turned down, considering how to proceed. Design of phase measurement experiment in CTF3 “dog-leg” under way by B. Woolley and I. Syratchev. PSI Hardware orders for a 'proof of principle' system are out, parts partially received and expecting to have everything by the end of the month. Part time position has been approved by PSI directorate, still needs to be published officially potential candidate identified. Currently preparing paper & presentation on raw measurements and signal characterization for IBIC 2012 (International Beam Instrumentation Conference). CEA/Saclay Software acquisition - 3D PIC code “CST particle studio” and tests of the evaluation version of the 2D/3D specific code MAGIC. Very preliminary calculations of the interaction structure of a 12 GHz klystron. Recruitment of a young scientist for a 2 year position: have the candidate and the contract has to be confirmed by CEA (we are very optimistic), expect to start in April 2014.

8. Task 12.3 High Gradient NC (Cont’d) Uppsala University Updating sub-task work plan. Manchester University Inna Nesmiyan, PDRA, appointed to work in EuCARD2 beam dynamics simulations -Impact of fabrication errors on beam emittance assessed. Initial results on structure alignment simulations complete. Alex D’Elia, PDRA (UMAN), appointed to work on EUCARD2 RF structure DDS development (liaising with CERN on production issues and simulating transverse wakefields in interleaved structures with GdfidL). CLIC_DDSA fabricated all 24 cells and diffusion bonded. It remains to attach couplers and tuning stubs.

9. Task 12.4 SRF HOM Diagnostics Collaboration with FNAL, ESS, KEK ongoing from EUCARD DESY Several new HOM electronics for 1.3 and 3.9 GHz cavities are being tested in the lab. First tests in the FLASH linac are planned before the end of the year. Also plan systematic studies of the HOM signals at the cavities in FLASH. PuneetJain, PDRA, appointed to work on XFEL cavities - modelling and shift exp. work, started in May. Manchester University A new PhD student, Liangliang Shi (registered at the Univ. of Manchester, based at DESY lab), started work in August. University Rostock In August, Thomas Flisgen, PDRA, appointed (25% of his working time) within EuCARD-2. Two papers in preparation one in IEEE Trans. Mag. article on modal absorbing boundary conditions, and one in PRTS-AB.

10. Task 12.5 RF Photocathodes • NCBJ and HZB Berlin • Surface preparation for lead coating underway. • HZDR and DESY • Preparation of PC plugs for measurements at ELBE in progress. • STFC • Construction and commissioning of a photocathode surface analysis and preparation installation (SAPI) is progressing: • New Kelvin probe for measuring work function successfully commissioned and the atomic force microscope (AFM) currently under test. • Studies of the plasma cleaning of copper photocathodes underway for use in VELA (formerly EBTF) NC RF gun: • Surface properties can be seen to be dramatically different for samples prepared using alternative plasma cleaning equipment. • On schedule for first Milestone (MS73) delivery in M8 (Jan 14).