1. Undulator Cavity BPM Status

2. Design Review Outline • BPM System Design Overview • Cavity Design • Electronics and ADC • Current status for phase I prototype testing • Planning phase II prototype test • First article and production

3. LTU and Undulator BPM System Specification

4. BPM System Overview Block Diagram

5. X-Band Cavity BPM Design • Each BPM has position cavity and reference cavity • SLAC selective coupling design utilized to reduce monopole mode • Iris couplers are precisely EDM into Solid Copper Body • Waveguide transition brazed to body

6. Cold Test Prototype • Non-vacuum cold test prototype • Accelerated design verification and cold test development • Removable end caps • Presently used to verify tuning effects and test fixture development

7. Before and After Brazing (ITS Prototype)

8. Prototype Cold Test (Dipole cavity 500 micron offset)

9. Baseline Design for Phase I PrototypeMiteq X-Band Low Noise Receiver • Existing product line • WR 75 Waveguide Interface • Low Noise Figure (2.7 dB) • Budgetary price for (3 channels) $6500.00

10. Prototype Receiver Specification

11. In-Tunnel Receiver Block Diagram

12. Prototype X-Band Low Noise Receivers • Conversion gain 28 dB • Over 60 dB dynamic range • Noise Figure 2.5 dB • IF bandwidth 40-80 MHz • Receiver noise floor -88 dBm assuming 20 MHz IF bandwidth • Cavity BPM Sensitivity: -54 dBm/0.2nC/1m

13. Phase I Injector Test Stand ITS Install single X-Band Cavity and modified off-the-shelf down converter receiver Mount BPM on two-axis translation stage Phase II LEUTL test with PC gun Install three X-Band Cavities BPMs Mount all 3 BPMs together on a two-axis translation stage BPM System Test Approach

14. Injector Test Stand (ITS) Beam Parameters • Charge- 1 nC single-bunch • Bunch length- ~ 3 - 4 ps FWHM for ps laser • Spot size on final screen at 5.5 MeV ~ 0.75 mm rms, ps laser

15. (Phase I) ITS BPM Test Results • BPM setup on X/Y translation stage • Aligned BPM Pitch and Yaw to < 25 m • Initial beam spot size 2-3 mm rms at low charge (0.05 nC) at faraday cup before adding new focusing magnetsto reduce to 200 um rms • Beam stability limited to 50 m rms. Laser improvements ongoing

16. ITS Data Processing Development • Cavity BPM and electronics tested using ITS beam line • First raw cavity voltage outputs captured on scope 6/9/06 • Mover system calibration • Testing is on-going following Aug/Sep shut-down Hor. Ref. Vert.

17. ITS Data Processing Development

18. Waveforms acquired with sampling scope and processed via Epics

19. Normalized waveforms 0.05 nC charge

20. Dipole Cavity Preliminary Test Data

21. (Phase II) 3 BPM Test Schedule Milestones • Refine design and develop First Article Cavity BPM and support hardware • August 06 • Start 3 BPMs • October 06 • First unit with accelerated delivery • October 06 • Install 3 cavity BPMs into APS LEUTL and Test • December 06

22. Prototype Phase II Cavity BPM Specification

23. Dipole Cavity Design • Beam pipe radius = 5 mm • Cavity radius = 14.937 mm (14.888 mm) • Cavity gap = 3 mm • Distance beam axis to bottom of wg = 9.5 mm (10.5 mm) • Waveguide= 19.05 x 3 mm

24. Monopole Cavity Design • Beam pipe radius = 5 mm • Cavity radius = 11.738 mm (11.477 mm) • Cavity gap = 2 mm (3 mm) • Coupling Slot = 2 x 4 mm (2.5 x 4 mm) • Tangent to surface of cavity opening to bottom of waveguide=1.734 mm (3.75 mm) • Waveguide= 19.05 x 3 mm

25. Tuning Pins Tuning Pins Feature Added • Tuning pins prototyped and tested in lab • Tuning pin simulations verify lab measurements • Tuning pins will improve performance and production yield

26. Design Development First Article Design ITS Test Unit Cold Test Unit

27. Receiver Design Changes • Packaged 3 channel receiver • High/Low gain feature (28/0dB) to extend dynamic range. • Add a simple CW tone self-test feature

28. Receiver Packaging Design • Receiver enclosure 12.5 wide by 11 deep by 2.5 thick (inches) with radiation shield cover • Houses input filters local oscillator and down-converter • 3-WR75 Inputs, 3-type “N” outputs, LO ref. input Type “N”, power and control cable

29. SLAC ADC Development • The PAD (Phase and Amplitude Detector) being considered for Cavity BPM ADC • Linear Technologies LTC2208 16 bit digitizer chip specified to run up to 130MHz

30. Phase II Data Acquisition Design Approach • Instrument three BPMs with SLAC Built 16-bit, 130 MSPS digitizers (PAD) • Epics driver available • Synchronize ADC clock with 119 MHz • Digitize horizontal, vertical position and Intensity 0 to 1 volt range • Digital down convert 40 MHz IF decaying exponentials

31. Phase II Testing Objectives 3 BPM Test • Test three BPM separated by fixed distance to determine single-shot • Evaluate First Article Prototypes • Complete test matrix to prove compliance to specification

32. System Layout and Planning Beam X-band receiver LRU

33. Production Phase • Production of 2 BPMs for LTU 04/07 • Production of 6 BPMs for undulator 04/07 • Production of 9 BPMs for undulator 06/07 • Production of 9 BPMs for undulator 08/07 • Production of 10 BPMs for undulator 10/07 • Spares 12/07

34. Summary • X-Band Cavity BPM development ongoing • Bolt-together prototype (non-vacuum) complete • ITS prototype testing ongoing • 3 BPM test prototype design enhancements ongoing • Receiver Prototype Development • First Prototype installed in ITS with good results • 3 BPM test prototype design incorporates high/low gain, self-test and final packaging • Data Acquisition and Test • Collaborating with SLAC to use the same ADC as SLAC LINAC BPM upgrade