Status of CTF3 G.Geschonke 1CTF3/CLIC Collaboration Board

Update on consequences of Fire 2CTF3/CLIC Collaboration Board fire in PFN on 4 th March Cleaning was finished on 23 rd April Cable repairs finished on 21 st May Restore power and switch on equipment testing of MKS03 in diode mode to define start up procedure for rest of modulators together with safety experts Patrols of machine, klystrons connected to machine, safety chain tests and beam permit for machine was granted on 23 rd June Procedure is now finished Total cost: about 2.1 MCHF insurance pays everything above 500 kCHF - who pays the rest?

Recommendations from enquiry into cause of fire The discharge resistors should have temperature interlock Low temperature melting wires Microswitches attached to wires.. Action turn modulator off

Recommendations from enquiry into cause of fire Redesign the energy discharge assembly paying particular attention to electrical clearances and cable routing. The control cable must not be routed anywhere near high voltage lines. This has been done in all modulators -Use of non-flammable materials for mounting surfaces is strongly recommended. -A ceramic mounting plate for the resistors has been designed and ordered (long term delivery item) and will be implemented in each modulator when the pieces arrive

Recommendations from enquiry into cause of fire Conduct infrared temperature mapping during commissioning. –This has been implemented into the start up procedure to be performed in each modulator - Improve event recording to system. –The interlock control units that register modulator trips are now on uninterruptable power supplies to ensure record of faulty (if any) –Working with control group to do remote task to register these events in the control database –Pulse to pulse interlocking (pulse shape etc. were working fine no need to modify Other actions: A study is ongoing to implement a smoke detection system at the output ventilation of each faraday cage that in case of alarm will automatically cut the modulator off while generating a level 3 alarm

The next disaster ? 6CTF3/CLIC Collaboration Board MTP: I was told, that the plan is to also include CTF3. ????? No running in 2012 ?????

Update on operation 7CTF3/CLIC Collaboration Board the burnt modulator will not be replaced before the winter shutdown. two accelerating structures removed from linac energy nearly same as before: MeV, (up to 112 MeV before) lower beam current – 3.5A (before 4A) push klystron power higher

Improvements 8CTF3/CLIC Collaboration Board CTF3 is mainly relying on stability of systems, originally no feedbacks. Stability improvements: phase feedback around klystrons implemented New electron gun heater power supply => better stability control on gun current during the pulse with external signal coming shortly

Frank Tecker CTF3 Committee RF compressor temp. feedback RF pulse compression cavities very sensitive to T variations now all klystrons with RF compressor have feedback ON recovers quickly after klystron trip => compressed RF flat top much more stable => current in TBTS more stable Alexey Dubrovskiy

Operation - Beam 10CTF3/CLIC Collaboration Board Beam established everywhere New BPM read-out system TL2, TBL, works fine Optics studies started give first beam to TBL/TBTS finally up to 7 Amps through TBTS PETS

Operation - Beam 11CTF3/CLIC Collaboration Board Delay Loop: Full transmission achieved (not combined) Combiner Ring: Recombination factor 4 with 3 GHz beam established Full factor 8 combination: several more weeks

Update on TBL activities  We had only a few occasions to run beam through TBL until now  Checked out hardware Testing of the new BPM acquisition system which seems to work fine now Testing of the quadrupole movers with remote control End of line spectrometer hardware and software New emittance screen at the end of the line Commissioning of new operation software  Measured beam parameters at the entrance of TBL and performed successfully matching for a 3 A beam which was transported to the end of the line  2.5 A==> 1.MW  Power measurement in the PETS confirmed that repair of water leak in the PETS tank worked out well  Waiting for more beam and higher current Steffen Döbert 12 CTF3/CLIC collaboration Board

TBL plans 13CTF3/CLIC Collaboration Board PETS are being manufactured. all pieces ready except PETS bars Install 2 more PETS tanks during autumn 2010 As soon as some experience with present design, order the remaining 8. Strategy to be defined. Complete beam line with all quads, quad movers, BPS, vacuum system installed

Two Beam Test Stand and Califes 14CTF3/CLIC Collaboration Board PETS in Drive Beam and accelerating structure in Probe Beam (Califes) now coupled. first test with two beams: 4 MW (60 MW nominal) ==>  E = 3.7 MeV Califes has new Phase shifter installed and successfully tested Now running regularly Bunch charge is about 10% nominal only so far TBTS

Schedule (updated) Optics improvements (DL dispersion) Full transport to CLEX Bunch length control (first tests) TBTS initial PETS tests CALIFES setup new setup when MKS13 available? PETS conditioned to nominal power/pulse length TBL PETS tests Accelerating structure conditioned to nominal power/pulse length PETS breakdown rate measurements??? Test of new PETS on-off scheme Two-Beam test power & energy gain, 100MV/m Beam Loading compensation experiment Measurement of breakdown kicks Measurement of effect of beam loading on breakdown rate 1 st TBL PETS installation PHIN possible 2 nd TBL PETS installation 6 weeks PHIN phase-coding Laser preparation TBL studies (limited) Stability studies & improvements PETS no recirculation Phase stability Operation at 5 Hz (or more) Control of beam losses Coherent Diffraction Radiation … TBL studies 30% deceleration ? Beam

PHIN run 16CTF3/CLIC Collaboration Board  Successful run for PHIN  We understand quite well the beam dynamics of the photo injector with CTF3 parameters  Full set of time resolved data was measured, beam seems stable along the pulse, we see the imperfections of subsystems  Studied charge limitation, need to find an answer for CLIC parameters Next run we might increase the laser spot further  Cathode life time seems to suffer with the long pulse Try a ‘very long ‘ pulse (5  s) next time to see effect towards CLIC  Shot to shot stability studied and seems reasonable  Phase coding and power feedback are the next big steps  PHIN-study almost finished  Study CLIC parameters in the future S.Doebert

Conclusion 17CTF3/CLIC Collaboration Board Operation well on track again. Lost about 18 weeks Short winter shutdown, start – up again as early as possible (end January?)