1 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC BPM energy spectrometer (T-474/491) Synch Stripe energy spectrometer (T-475) Collimator design, wakefields (T-480) Bunch length diagnostics (LOLA, 90GHz diode, T-487) IP BPMs/kickers—background studies (T-488) LCLS beam to ESA (T490) Linac BPM prototypes EMI (electro-magnetic interference) ILC Beam Tests in End Station A SLAC ILC R&D Meeting, April 16, 2007

2 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC 6 test beam experiments approved: T-474/491, T-475, T-480, T-487, T-488, T Runs: i.January 5-9 commissioning run ii.April 24 – May 8, Run 1 iii.July 7-19, Run Runs i.March 7-26, Run 3 completed ii.July 5-8, T490 w/ LCLS beam (dates tentative) iii.July 9-22, Run 4 (dates tentative) + requesting two 2-week runs in FY08 ILC Beam Tests in End Station A

3 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC ESA Equipment Layout 18 feet 4 rf BPMs for incoming trajectory Ceramic gap w/ rf diode detectors (16GHz, 23GHz, and 100GHz) and 2 EMI antennas Wakefield boxWire Scannersrf BPMs blue=FY06 red=new in FY07 Upstream (not shown) Dipoles + Wiggler T-487: long. bunch profile FONT-T488 Ceramic gap BLMs Ceramic gap for EMI studies T475 Detector for Wiggler SR stripe Downstream (not shown)

4 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC March 2007 Run Run Co-ordinator: Steve Molloy ~40 Run Participants, www-project.slac.stanford.edu/ilc/testfac/ESA/TestbeamRuns/March2007/March2007_Run-Participants.xls Safety: ESA facility: Carsten Hast Counting house facility: Zen Szalata User JHAMs, safety courses, controlled access training: Steve Molloy and Mike Woods Co-ordinated and received operations approval from SOC, Radiation Physics, Electrical Safety, Earthquaking: Ray Arnold, Carsten and Zen Safety instructions for users at www-project.slac.stanford.edu/ilc/testfac/ESA/safetytraining.html;www-project.slac.stanford.edu/ilc/testfac/ESA/safetytraining.html Documentation kept for user safety training: 3 safety courses, JHAMs, Controlled Access training ESA Beamline and User installations: ready for beam by March 8 Beam Delivery: first beam ~1 day late, March 9 Beam setup took longer than expected; problems with broken S28 wire, large Linac emittances, unable to use Q30 at end of A-line due to water leak; collimator only partially open in A-line Beam setup help from Rick Iverson, Janice Nelson, Frank Jackson assisting operators Run completed successfully March 26

5 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC March 2007 Run Summary T-474/491: 4 chicane dipoles were installed and successfully operated; we have 1NMR probe/magnet and 1 Hall probe in first magnet; have 2 fluxgate probes (0-5gauss) to monitor stray fields new BPM electronics and calibration system from UK collaborators; 1 of the (SC) Linac quad bpms on remote mover moved to mid-chicane location; interferometer reconfigured to monitor horizontal motion of mid-chicane bpm; T-475 prototype detector installed for background measurements (no Wiggler until july run); T new sets of collimators for wakefield measurements; 6 of 7 successfully measured T-487 Smith-Purcell bunch length diagnostics: first measurements made for this new experiment T Al radiator foils, 1-5% rad. Lengths, upstream of bpm module can be inserted in beam—to provide backgrounds and primary beam simulataneously; also repeated measurements done in previous run steering low intensity beam onto “Beamcal”; EMI ceramic gap relocated to “cleaner” location between 3B1 and 3B2 dipoles studied failure modes for SLD vertex electronics with different shielding setups for gap

6 SLAC ILC R&D Meeting, 16-Apr-2007 LCABD WP 4.2 Review, 12 th April Mark Slater T474 upgrades for March Run Zygo Interferometer Relocated BPM4 10D37 Magnets  There were a large number of hardware updates for the April Run:  Installed and tested the full spectrometer chicane  Commissioned an additional energy BPM at high dispersion  Relocated interferometer  Commissioned new UK electronics, and calibration tone system  Developed a new calibration scheme using Helmholtz coils rather than correctors

7 SLAC ILC R&D Meeting, 16-Apr-2007 T474 Data from March Run Helmholtz coil dithering for fast BPM calibrations Adc channel monitoring BDES to ycoil Y position (mm) at BPM3 in ESA 0.5-micron resolution Energy Scan measured with ESA Chicane BPMs

8 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC T-480: Collimator Wakefields 7 New Collimators for Run 3 were fabricated; 6 of 7 measured (+1 with same geometry as Run 2 for cross check)  Compare importance of tapers in region away from gap centre –  acceptable to have shallow tapers necessary for transverse wakefield performance only in the immediate vicinity of beam axis?? (Can we make much shorter collimators?)  Flat section introduced equivalent in length to 0.6 r.l. of Ti6Al4V  Explicit tests of surface roughness  Allow one slot for non-linear taper, exponential form

9 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC Collim.# Side viewBeam view Revised 27-Nov  166mrad r=1.4mm (1/2 gap) 10  =166mrad r =1.4mm 11  =166mrad r =1.4mm 12  166mrad r=1.4mm h=38 mm 38 mm Roughened surface, compare with 12 As 10, in Ti-6Al-4V, polished, cf. 12 As 10, in OFE Cu, polished, cf. collim. 6, 13 Runs 3, 2007 Exists, from 2006 runs. For reproducibility ~211mm 1.4mm  =21mm   

10 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC Collim.# Side viewBeam view Revised 27-Nov  1 =  /2 rad  2 =166mrad r 1 =4.0mm r 2 =1.4mm 14  1 =  /2 rad  2 =166mrad r 1 =4.0mm r 2 =1.4mm 15  1 =  /2 rad  2 =50mrad r 1 =4.0mm r 2 =1.4mm 16? non-linear taper r=1.4mm h=38 mm 38 mm cf. ? Polished, cf. collim. 13 Polished, cf. collims. 7, 11, 13 Polished, cf. collim. 7, 12, 13 Ti6Al4V OFE Cu =21 mm Form t.b.d. = 0.6   Ti6Al4V Runs 3, 2007 ~52 mm =21 mm  ~52 mm =21 mm   ~125 mm =21 mm

11 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC Collects and concentrates the light seen. Winston Cone Waveguide Array Plate Filter Far infrared filter, designed to reject non- SP wavelengths. 11 Pyroelectric Detectors Inexpensive, room temperature detectors. Carousel of 3 gratings and ‘blank’ Quartz Window Expands observable wavelength range. Quick measurement turnaround. Allows ‘true’ SP signal to be found (i.e. ‘grating – blank grating’ signal = true SP signal). T487: Longitudinal Bunch Diagnostics for the ILC PI: G. Doucas (Oxford U.), Collaborating Institutions: U. of Oxford, Rutherford Appleton Lab, U. of Essex, Dartmouth College, SLAC G. Doucas

12 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC T487 – Prelim. Analysis for March Run First ever ( to our knowledge) SP experiment in the GeV region. Analysis of the SLAC data is in the very early stage. Need cross-referencing of detector responsivities. Also, absolute detector calibration (not easy). However, initial impressions from the data are very encouraging: New electronics performed well. Good signal-to-noise ratio. a change in the SLAC bunch length was clearly observable. overall signal levels and onset of signal saturation suggest a bunch length with a sigma of about ps (90% of the particles inside 5-6ps). Current analysis method is a Least Squares fit to a number of ‘template’ distributions; in progress, with specially developed code. It provides an approximation to a simple profile, but not a unique answer. Alternative analysis may be possible. G. Doucas

13 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC Two sets of data from the 1.5mm grating (Charge=1e10) Template curves are asymmetric gaussian bunch profiles. Assumed bunch length=5ps (90% of particles) Measured levels are lower than expected for this bunch length (  requires accurate detector calibration) Overall signal level and rise towards ‘saturation’ suggest a bunch length of about 5-6ps (90% of particles) T487 – Preliminary Analysis from March Run G. Doucas

14 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC Top trace: VXD board phase-lock loop signal Other traces: the two EMI antennas. Time offsets are due to cable length differences. EMI Studies w/ SLD vertex electronics SLD VXD electronics YAGI Antenna Biconical Antenna (N. Sinev, Fermilab SiD Workshop April 7, 2007)

15 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC A single layer of common 5mil aluminum foil was placed over the ceramic gap and clamped at both ends to provide an image current path. The antenna signal amplitude was reduced by >x10. EMI from upstream sources limited the resolution. The aluminum foil gap cover stopped VXD failures. A 1 cm x 1 cm hole in the gap foil cover emitted enough EMI to cause about 50% VXD failure rate at ~1m distance. (With no foil rate would be 100% at this distance.) There was no failure with a 0.6 cm x 0.6 cm hole. EMI Tests, 2006 The VXD module phase lock loop lost lock on about 85% of beam crossing when the module was exposed to ~20 V/m of EMI. The VXD module lost lock about 5% when exposed to ~1 V/m of EMI. EMI Shielding Tests, March 2007 (N. Sinev, Fermilab SiD Workshop April 7, 2007)

16 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC July Run: T-474 +T-475  additional BPM7 on mover system at mid-chicane  install wiggler and T-475 detector  compare results from BPM, synch stripe msmts and upstream beam diagnostics BPM 3,5 BPM 4,7 BPM 9-11 D1 D2D3 Vertical Wiggler D4 3D2 R. Arnold + T-475 quartz fiber detector downstream: 100-micron quartz fibers on 200-micron pitch (expect <1 micron accuracy) 32 fibers sampling sychrotron stripe on each side of beam pipe for 2 polarities ~50mm displacement between wiggler synchrotron stripes for 2 polarities readout with 64-channel multi-anode PMT and CAEN VME adcs

17 SLAC ILC R&D Meeting, 16-Apr-2007 M. Woods, SLAC July 2007 Run: dates are still tentative; need to co-ordinate with LCLS schedule major installation items are the wiggler and detector for T-475 energy spect. will also install new UK BPM w/ mover at mid-chicane location plan to take data for T474, T475, T480, T487 and EMI studies also plan to characterize emittance in ESA with LCLS beam, T-490 FY08 Runs: uncertain primarily due to lab funding problems for ESA infrastructure, but ILC budget projections for FY08 are good and discussing how to accommodate a focused ILC program in ESA in FY08. Meeting with myself, Persis, Tor and David MacFarlane on We have a very strong and successful program with lots of user interest, in particular for the collimator wakefield and energy spectrometer programs. ESA has unique capabilities for this. Also investigating how our setup can be used to test micron-level stability relevant for ILC Linac quad/bpm modules.