FACET Update ARD Status Meeting Christine Clarke April 14 th 2011

FACET Update Page 2 The FACET Project Facilities for Accelerator science and Experimental Test beams. FACET ESA ESB

Beam at FACET FACET Update Page 3 At IP FACET uses the first two-thirds of the linac Energy = 23 GeV 3.2 nC Sigma x = 14 um Sigma y = 6 um Sigma z = 14 um minimum (20 um typical) Bunch length can be increased up to a factor of 3 Electron beam (2011)

The Facility FACET Update Page 4 Stairway in Sector 19 User Trailer ExperimentsDump Towards end of linac Beam Direction

Plan – THz and IP Tables FACET Update Page 5 Optical Tables for experimenters to mount hardware Optics set up for each experiment Small beam spots in IP region THz Table (Experimental Area 1) IP Table (Experimental Area 2) Beam Direction

THz and IP Optical Tables FACET Update Page 6 THz Table (looking east towards dump) IP Table (looking east towards dump) Photos taken Feb 11 (Mark Hogan) Magnets installed since then.

March… Some magnets installed in sector 20 – photo taken March 16 th : FACET Update Page 7 THz Table (looking east towards dump) IP Table

April… All magnets in sector 20 – photo taken last Tuesday : FACET Update Page 8 THz Table (looking east towards dump) IP Table

Close-up of THz Beamline almost complete FACET Update Page 9 Initial THz diagnostics with OTR foils (1um titanium) Cubes Beam here large in x (>1mm) Future location of Smith-Purcell experiment.

Close-up of IP Table Could be complete end of next week FACET Update Page 10 IP experiments located here (second table to come). For tuning, vacuum drifts, wire scanner and OTR screens.

SAREC Final Report SLAC Accelerator Research Experimental program Committee Convened in January to review 8 proposals 6 proposals accepted as Experimental Programs 1 proposal incorporated into FACET diagnostics (ODR) 1 letter of intent – requested to present two proposals in the next round. 1 expression of interest – asked to make preliminary measurements this summer (THz). Second call for proposals this fall for the spring 2012 and 2013 runs SAREC review in the early winter of FACET Update Page 11

Plasma Wakefield Acceleration FACET Update Page 12 Continuation of very successful FFTB experiments Heat-pipe oven to be installed this July Lithium metal vaporized at 800ºC Length of plasma controllable by controlling heaters and pressure of helium buffer gas Phase One: Begin with single electron bunch in field ionized lithium plasma. Phase Two: Single bunch in field ionized cesium plasma. Phase Three: Use Notch Collimator. Phase Four: Two electron bunches (drive and witness) in field ionized cesium plasma. After first year, pre-ionized plasma, positrons, positrons and electrons.

Smith Purcell FACET Update Page 13 Bunch Time Profile measurements with Coherent Smith-Purcell Radiation Moderate band-width terahertz Beam passes by grating which has a dispersive effect Continuation of experiment at ESA Not sensitive to beam spot size (will be situated upstream of IP). Non-destructive (parasitic running).

Wakefield Acceleration in Dielectric Structures FACET Update Page 14 GV/m class DWA for use in linear colliders and future light sources. Previous work at FFTB/SLAC, UCLA, BNL. High gradient regime at FACET. FACET beam sent through prototype dielectric wakefield acceleration structures. Parametric breakdown studies and lifetime effects. Vary structures (dimensions, materials etc). Use drive and witness bunches to observe acceleration. Use coherent Cerenkov radiation Next year, use protons.

Ultrafast Magnetic Switching Continuation of FFTB work. Change in magnetization of a sample on ultrafast timescales Change pulse-lengths with constant Q - do longer pulse-lengths have more energy deposition? Expose sample to electron bunch Then image with spin-sensitive scanning electron microscope. Different patterns on same film indicate different physical processes. Chaos cannot be explained Need to rule out experimental artefacts. FACET Update Page ps 70fs

Additional Experiments Metallic Periodic Structures (Accepted Proposal) –Short-pulse, high fields to study breakdown physics. High gradient dielectric wakefield measurements (Accepted Proposal) –dielectric based collimating systems CLIC Studies (letter of intent) –Dispersion-free steering –Accelerating structure Wakefield Studies –Collimator Wakefield Studies THz extraction (expression of interest) –Extract radiation to an experimental area FACET Update Page 16 30cm High Power test structure (CLIC Studies) Suggested extraction of THz Short Metallic Accelerating Structure

Schedule 2011 Construction Phase 1 will be complete in May. Beam Commissioning starts June 13 th Experiments are installed July 5 th - July 14 th Experimental program in August Users meeting August 29 th /30 th Next round of proposals coming up (fall) Construction Phase 2… positron arm of the bunch compressor in S10 Experimental PPS zone FACET Update Page 17

Schedule 2012 and Beyond FACET will run for 4 months each year for the next five years. In 2012 the 4 months are likely to be February - June. Electron beams and positron beams will be available to the experimenters. 2013? Phase Three: positron arm of the bunch compressor in S20 (aka the sailboat chicane) for simultaneous electron and positron beams FACET Update Page 18

Summary FACET is currently near the end of its primary construction phase. First Beam June 13 th Approximately 3 weeks of beam commissioning, some User assistance. User aided commissioning / experiment commissioning program, August. New round of proposals for 2012 due (provisionally) October. 4 months of FACET running in 2012 and every year until FACET Update Page 19