Accelerator Physics and Engineering Update Jan 6, 2010 Josef Frisch Tonee Smith Clive Field Alan Fisher Henrik Loos Christopher Behrens (NEW!) Nate Lipkowitz (NEW!) Jeff Rzepiela Mark Petree Steve Smith Jim Welch Glen White Walter Wittmer Mark Woodley Gerald Yocky

APE: What we do Physics Engineering Operations Whatever it takes to make accelerators work Some long term planned projects Some kludges to get systems working E-beam optics Light optics X-rays Detectors Applications Modeling RF Electronics Acoustics Vacuum Mechanical PowerPoint

Beam Arrival Time Monitor Problem Phase cavity difference noise has been increasing since October Increase from 12 to ~50 femtoseconds RMS Difficult to debug: still smaller than raw beam jitter, no signal when beam is off. Not yet the dominant noise source, but will be soon! In addition to short term fix, need an independent check: 3rd phase cavity?

Future Timing Previous meeting mentioned using an optical / X-ray cross-correlator. X-rays Reflected optical beam measured on array sensor Laser GaAs or similar Tests at SXR (W. Schlotter et al) have demonstrated 60fs RMS single shot X-ray to laser optical timing measurement. Note that electronic timing will still be needed for “crude” 100fs timing

Cross Correlator (very preliminary) (SXR) M. Beye B. Schlotter W. Schlotter et al. (LCLS)

Materials Damage and Wavefront Distortion Tests Fused Silica damages Damage Speckle from Be attenuators led to search for alternate materials Damage and wave front distortion tests indicate that Al2O3, Diamond and SiC all are OK. 3D map of damage to SiO2 Sample

Be Lens to be Installed in LCLS X-ray diagnostics chamber Reduce divergence to (incorrect) design B. Lenegeler, J. Krzywinski, E. Kraft, et al. (Engineering, LCLS, APE, etc)

Broadband IR Spectrometer for Bunch Length Measurement Measure spectrum of OTR light from short bunches to estimate bunch length Need single shot, very broadband ~50:1 low resolution (25%) spectrometer Operating range ~0.8 –40 microns Optics design done, prototype parts on order Parabolic mirror Prism, KRS-5 Tilted image plane corrects aberrations OTR foil Christoph Behrens Henrik Loos Jennifer Loos Sasha Gilevich Pyroelectric Array detector Parabolic mirror

THz Emitted THz power GaAs z-scan THz system for LCLS now being commissioned. Working with Pulse, and Stanford have first demonstration experiments with THz Alan Fisher will discuss in detail in next talk. Emitted THz power GaAs z-scan D. Daranciang et. Al.

LHC Synchrotron Light Monitor Lead Ions at 2.3 TeV A. Fisher will discuss in next talk

ATF2 Recent Results 4 OTR screens now provide reproducible emittance measurements in less than a minute, rather than hours for the wire scanners (1.5 Hz beam). 25 Cavity BPMs now working at <50nm resolution Spot size monitor not working in high resolution mode (ATF2 group) Automated Dispersion Correction G. White, M. Woodley, S. Boogert, T. Smith

Other Projects 120Hz upgrades FACET bunch length monitors Time-slot aware feedbacks: Big project from Controls and APE. Accelerator now at 120Hz with good time-slot. FACET bunch length monitors (similar to LCLS) Diagnostics and control applications Ongoing efforts to automate machine operations Thermal-acoustic X-ray calorimeter Passed Vacuum check Install in late January.