1. Linear Collider For Japan-US HEP Program Committee April 2004 Nobu Toge (Accelerator Lab., KEK)

2. Japan-US HEP Program Committee Mtg2 April 13, 2004 LC R&D under Japan-US Participants  Accelerator Lab and IPNS, KEK  Nagoya, Tohoku-Gakuin, Yokohama National, Tokyo Metropolitan, Kyoto, Tokyo, Saitama, NIRS  SLAC, LBNL, LLNL, FNAL, BNL Research subjects  Development of microwave technologies for the main liancs.  Technologies for production and control of ultra-low emittance  Variety of collaborative / cooperative activities around the two topics above (e.g. IR issues, cost evaluation studies) LC ISG (International Study Group)  General meeting: one in June at SLAC, another in December at KEK Visits ：  Japan  US: approx. 40 man.weeks + 1 accounting officer  US  Japan: approx. 30 man.weeks

3. Japan-US HEP Program Committee Mtg3 April 13, 2004 Layout of GLC

4. Japan-US HEP Program Committee Mtg4 April 13, 2004 Development in JFY2003 Collaboration on critical R&D items concerning the X-band main linac technology.  Topics as laid out in “R1, R2” items summarized in the TRC-II report.  Some efforts conducted in parellel, some jointly at NLCTA.  Many of the R1, R2 goals have been achieved. Efforts to clear some remaining ones will continue in JFY 2004. Strong participation by the SLAC/LBNL teams at ATF of KEK.  Development of beam control techniques.  Started formal efforts on “nano-BPM” project. ISG (International Study Group) Meetings.  Latest information from ISG-11 at ： http://lcdev.kek.jp/ISG/ISG11 http://lcdev.kek.jp/ISG/ISG11  Continue in JFY2004

5. Japan-US HEP Program Committee Mtg5 April 13, 2004 Basic RF unit for GLC-X/NLC Main Linacs 56MW

6. Japan-US HEP Program Committee Mtg6 April 13, 2004 Accelerator Struc (TRC R1#1) Issue: Validate the gradient and trip rate performance of structures with an acceptable iris radius, dipole mode detuning and manifolds for damping. Goal: < 0.1 BD/hr in operation at 65MV/m, 400ns, rep rate normalized at 60Hz. Results in 2003 ：  Most structures tested in 2003 have a/l ~ 0.17 and with HOM manifolds and detuning.  Some gave < 0.1 BD/hr at 60MV/m.  ~ 0.2 – 0.3 BD/hr at 65MV/m  However, with the “trapezoidal pulse shaping” required in actual LC operation for beam loading compensation, with 65MV/m flattop, 0.1BD/hr is nearly achieved. Time Field

7. Japan-US HEP Program Committee Mtg7 April 13, 2004 Test Accelerator Structures  Cells (fabricated by KEK) Structure (Assembled by SLAC ） 

8. Japan-US HEP Program Committee Mtg8 April 13, 2004 Summary of Tests （ 2002-2003 ） All H60 struct’s built in 2002- 2003. BD rate ~ Exp(Gradient) OK with 60MV/m 65MV/m sees BD rate too high by factor 2 or above. “Design pulse shape” gives substantially reduced BD rate. Observed factor ~5 variation of BD rate with various structures. Some are due to known variations of build and heat processing conditions. Need to establish statistically more credible data from testing of structs with identical designs and builds.

9. Japan-US HEP Program Committee Mtg9 April 13, 2004 Structure R&D in JFY 2004 KEK builds cells for at least two more H60VG4S17-type structs (with HOM manifolds), which will be assembled at SLAC, and be tested in Spring, 2004.  In addition, two more 60cm structures with complete HOM extraction in Spring- Summer. SLAC will expand the test station capability for operating up to 8 test struc’s concurrently in Spring, 2004. Based on their results, we will determine the studies items of focus in the 2 nd half of 2004. For instance,  More optimization of designs (improved shunt impedance, etc)  Global parameter reoptimization of LC.  Shift to industrialization issues In parallel, KEK will accelerator efforts on ：  Japanese capability of building 60cm strucs  GLCTA at KEK (Japanese LC linac test facility) Most of their funding come from separate Japanese budget, however.

10. Japan-US HEP Program Committee Mtg10 April 13, 2004 SLED-II (TRC R1#2) Issue: Critical element of the RF system is the dual- moded SLED-II pulse compression system. Tests of its RF power and energy handling capability at GLC- X/NLC design levels are planned in 2003. Goal ： Production of 475MW, 400ns. Resutls in 2003:  475MW, 400ns was achieved on12/4/2003, operation at 30Hz for 100hrs.  Maximum record: 580MW, 400ns.  Used 4 solenoid-focusing type klystrons as power sources rather than a pair of PPM klystrons.

11. Japan-US HEP Program Committee Mtg11 April 13, 2004 56MW R1#2 Solenoid tubes x 4 were used in 2003.

12. Japan-US HEP Program Committee Mtg12 April 13, 2004 Schematic view of the SLED-II Test Site at SLAC (Fall-Winter, 2003)

13. Japan-US HEP Program Committee Mtg13 April 13, 2004 Input/Output pulses of SLED-II

14. Japan-US HEP Program Committee Mtg14 April 13, 2004 SLED-II R&D in JFY 2004. Done with R1#2. Shift to R2#2. i.e.,  Distribution of RF power from SLED-II output to accelerator structures.  Long-term operation at 60Hz.  Eventually drive SLED-II with PPM klystrons rather than solenoid-focusing type tubes.

15. Japan-US HEP Program Committee Mtg15 April 13, 2004 Klystron R&D (TRC R2#1) Issues: There must be a full test of the PPM klystron at the specified repetition rate of 120 or 150 Hz. Goal ： Simultaneous achievement of 75MW,1.6  s, rep rate120Hz or higher. Results in JFY 2003:  SLAC XP3-3 cleared the goal above in Fall, 2003 for a short period.  XP3-3 operated for one week with 65MW,1.6  s, 30Hz.

16. Japan-US HEP Program Committee Mtg16 April 13, 2004 56MW R ２ # １の範囲

17. Japan-US HEP Program Committee Mtg17 April 13, 2004 SLAC XP3-3

18. Japan-US HEP Program Committee Mtg18 April 13, 2004 More on PPM Klystrons in JFY2003 GLC-X PPM#2 (tested at SLAC in Spring, 2003 ） :  75MW, 1.7  s, 50Hz -- established  68MW, 1.7  s, 120Hz -- cleared However, frequent gun BD began. Tube was brought back to Japan and the repair strategies are under examination. GLC-X PPM#4 (tested at KEK in Summer-Winter, 2003 ）：  75MW, 1.7  s, 50Hz -- established After repairing RF windows, operation was confirmed and the tube is currently in a storage GLC-X PPM#5 (testing under way at KEK in Spring, 2004)  ~ 70MW, 1.6  s, 25Hz -- after 4 wks of operation NLC XP3-4 (testing under way at SLAC ）：  ~ 75MW, 1.6  s, 25Hz -- after 3+ wks of operation  XP3-5 is also under baking.

19. Japan-US HEP Program Committee Mtg19 April 13, 2004 Klystron R&D in JFY2004 (R2#1  R2#2) Existing PPM klystrons from KEK  PPM#4 ： reserved for demonstration at ITRP visit to KEK  PPM#5 ： reserved for demonstration at ITRP visit to KEK  PPM#2 ： re-testing planned at KEK after repair. PPM at SLED-II  Two out of PPM#4, #5, (#2), XP3-4 or XP3-5: Long-term testing at 120Hz. Also to eventually drive 2-moded SLED-II. Further design improvement  Improved reliability of cooling systems and electron gun, etc.

20. Japan-US HEP Program Committee Mtg20 April 13, 2004 Systematic Long-Term Operation of a RF unit (TRC R2#2) in JFY2004 Issues ： These klystrons should be tested with the NLC modulator and form part of a linac subunit test. The latter should also comprise the 2-moded SLED-II complete system, several damped and detuned structures, installed in the accelerator environment and LLRF and control systems. The test should be made with beam. Goal ： 475MW, 400ns output from SLED-II to be fed to max 8x60cm accelerator structures running at 65MV/m at initially 30Hz, eventually at 60Hz or higher. Status as of now:  Preparation under way

21. Japan-US HEP Program Committee Mtg21 April 13, 2004 56MW R２#２R２#２ Phase 1Phase 2 addition Switch to 2x PPM tubes later

22. Japan-US HEP Program Committee Mtg22 April 13, 2004 Plans for JFY2004 Phase-1 （ Spring, 2004@SLAC ） :  Keep 4 x solenoid klystrons.  KEK hybrid elements to use in power distribution  Half SLED-II output to be distributed to 4 x 60 structures.  Use previously-processed structures, initially.  Aim at operating at 60Hz  In this period, test structures will be separately processed with old (long-established) NLCTA RF sources. Phase-2 (Summer/Fall 2004@SLAC ）  Full SLED-II output to be distributed to 8 x 60cm strucs.  Long-term operation at 60Hz Klystrons （ Late Spring/Summer 2004@SLAC ）  Long-term 120Hz test stand offered by a new “2-pack” modulator.  Wish to use 2 x PPM tubes to drive the 2-moded SLED-II eventually.

23. Japan-US HEP Program Committee Mtg23 April 13, 2004 Nano BPM at ATF/KEK LLNL Design: R&D of mover technology with ultra- high precision with applications at IP and elsewhere.

24. Japan-US HEP Program Committee Mtg24 April 13, 2004 Proposed Budget Composition JFY 2004 (Subject to adjustment with final allocation to the program) Modulator25,000KY Klystron114,000KY SLED-II91,000KY Acc.Struc90,000KY Office / GA22,400KY Sum342,400KY