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Welcome!. Mauro Pivi SLAC, ESTB Workshop March 2011, SLAC. Workshop Logistics. If you didn’t already, please: Pick-up badges Sign-up for End Station A tour with Naomi. Sign up and give Naomi $45 for the d inner restaurant. Need a count. do these during the coffee break!.
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Welcome! Mauro Pivi SLAC, ESTB Workshop March 2011, SLAC
Workshop Logistics • If you didn’t already, please: • Pick-up badges • Sign-up for End Station A tour with Naomi. • Sign up and give Naomi $45 for the dinner restaurant. Need a count. • do these during the coffee break! Mauro Pivi SLAC, ESTB Workshop March 2011, SLAC
Workshop Logistics • ESA tour: • Let’s gather here outside • We will use vans • Afternoon session starts at 1:30pm! • Dinner: 7pm Hunan Garden Restaurant, Palo Alto. Mauro Pivi SLAC, ESTB Workshop March 2011, SLAC
ESTB End Station Test Beam Design, Performance, Infrastructure, Status Mauro Pivi SLAC National Accelerator Laboratory on behalf of ESTB/ESA team ESTB 2011 Workshop, SLAC March 17, 2011
SLAC End Station A Test Beam (ESTB) • Test beam activities have been interrupted by ending PEP II operation and start of LCLS • • ESTB will be a unique HEP resource • - World’s only high-energy primary electron beam for large scale Linear Collider MDI and beam instrumentation studies • - Exceptionally clean and well-defined secondary electron beams for detector development • - Huge experimental area, good existing conventional facilities, and historically broad user base • - Secondary hadron beams available as an upgrade Carsten Hast, SLAC, Test Beams in the US, October 2010, FNAL
ESTB proposal R. Erickson, T. Fieguth, C. Hast, J. Jaros, D. MacFarlane, T. Maruyama, Y. Nosochkov, T. Raubenheimer, J. Sheppard, D.Walz, and M. Woods, “ESTB proposal” July 2009 L. Keller, myself joined 2010
LCLS uses 1/3 of SLAC LINAC End Station A Presentation Title Page 7
LCLS and ESA Use pulsed magnets in the beam switchyard to send beam in ESA. Mauro Pivi SLAC, ESTB 2011 Workshop, Page 8
ESA LCLS A-Line BSY Presentation Title Page 9
Beam ESA Experimental Area Carsten Hast, SLAC, Test Beams in the US, October 2010, FNAL
LCLS beam parameters and range • LCLS beam • Energy: 3.5 –13.6 GeV • Repetition rate: 120Hz • Beam current: 20 to 250 pC • 150 pC preferred by LCLS Users • 350 pC @ 120Hz has been provided • This is the current upper limit for the present cathode • Beam availability ~95%! See also next presentation by Rick Iverson Mauro Pivi SLAC, ESTB 2011 Workshop
ESTB parameters • ESTB beam • Kick the LCLS beam into ESA @ 5 Hz • Primary beam 4 -13.6 GeV • Determined by LCLS • <1.5 x 109 e-/pulse • Clean secondary electrons • Up to 13.6 GeV, 0.1/pulse to 109 e-/pulse Mauro Pivi SLAC, ESTB 2011 Workshop
ESTB parameters 0.25 nC 0.25 nC Mauro Pivi SLAC, ESTB 2011 Workshop
Kicker Magnets • 4 new kicker magnets including power supplies and modulators and vacuum chambers are designed and components are being ordered and manufactured • Build new PPS system and install new beam dump Carsten Hast, SLAC, Test Beams in the US, October 2010, FNAL
ESTB Stage I: Primary e- Beam operations • ESTB can operated in several modes. • In Stage I: • A full intensity, high energy e- beam can be delivered to ESA • The beam is brought to a focus in the middle of ESA sx~sy~7um. sz=280um factor 28 larger than LCLS due to large R56 in A-line.
ESTB Stage I: Secondary e- beam • Primary beam can be directed onto a target: • Secondary e- are momentum-selected • Transported to ESA and focused to small spots • Adjusting 2 existing collimators, it is possible to provide secondary beams up to incident energy and down to 1 single particle/pulse. Mauro Pivi SLAC, ESTB 2011 Workshop
ESTB Stage I: Secondary e- beam • (Left) Spectrum of secondary e- beam from 13.6 GeV primary beam and (Right) transmission rate over each collimator. Adjusting 2 collimators, down to 1 e- /pulse. Mauro Pivi SLAC, ESTB 2011 Workshop
ESTB Stage II: Hadron beam line • For ESTB Stage II, • a secondary target upstream of ESA and • a beamline diverging at 1.35 degrees wrt straight ahead beamline (see more: Carsten Hast talk) • will provide a secondary hadronbeamline in ESA, with: • p produced at rate 1/pulse for 0.25nC beam. Rate can be farther reduced. • Protons and Kaons at ~ 0.02/pulse. • Cherenkov and time-of-flight detectors, which can tag the produced hadron cleanly. Mauro Pivi SLAC, ESTB 2011 Workshop
ESTB Stage II: Hadron beam line Scale to beam current 0.25nC Presentation Title Page 20
Tagged photon beam in ESA GLAST tests • A secondary e- beam is momentum-selected in the A-line and incident on a thin radiator in ESA. The scattered electron energy is measured in a calorimeter (Pb glass), tagging the photon energy: • capability exists but needs infrastructure • we should determine user need first • Does anybody (really) want this? Let us know! Mauro Pivi SLAC, ESTB 2011 Workshop
Short-termplan: “Pre-Stage I” • The complete 4 kickers system will not be ready until the end-of-summer. We adopt a short-term solution and plan to install during this down time: • 1 Kicker magnet with stainless steel chamber • Beryllium target • System designed for 60 Hz, might work at 120 Hz Mauro Pivi SLAC, ESTB 2011 Workshop
Short-term plan: “Pre-Stage I” • In this configuration, we either steer the: • 4 GeV full intensity LCLS beam into ESA. • 4 - 13.6 GeV primary beam into target and generate secondary e- beam to ESA, 0.1/pulse to 109/pulse. Mauro Pivi SLAC, ESTB 2011 Workshop
Short- and Long-Term Plans November 2011 by 2012 Mauro Pivi SLAC, ESTB 2011 Workshop
ESA Infrastructure Available InstrumentationTrigger counters Halo veto counters High resolution beam hodoscope Particle ID (Cerenkov, TOF, shower counter) Small, high field solenoid sturdy support table with remote movers Cranes 15 and 50-ton cranes available Carsten Hast, SLAC, Test Beams in the US, October 2010, FNAL
Wakefield box Wire Scanners “IP BPMs” T-488 rf BPMs Ceramic gap for EMI studies 18 feet T-487: long. bunch profile Dipoles + Wiggler BPM energy spectrometer (T-474/491) Synch Stripe energy spectrometer (T-475) Collimator design, wakefields (T-480) Bunch length diagnostics (T-487) Smith-Purcell Radiation IP BPMs—background studies (T-488) LCLS beam to ESA (T490) Linac BPM prototypes EMI (electro-magnetic interference) Irradiation Experiments ESA Past Experiments Carsten Hast, SLAC, Test Beams in the US, October 2010, FNAL
Energy Spectrometer chicane and wiggler • At ILC, precision of 100-200 ppm are needed for determination of particle masses, t and Higghs. • Chicane for BPM and SR stripe energy spectrometer T-474 & T-475 measurements in ESA • See M. Hildreth presentation and poster @ tour of ESA Mauro Pivi ESTB 2011 Workshop, Page 27
Collimator Wakefields • Collimators remove halo particles • Concern: short range wakefields • Tests: optimal materials and geometry to minimize wakefields • T-480, see tour @ ESA • “Wakefield box” allows swapping of collimators and adjusting jaw aperture • measured wakefield kick to the beam by downstream BPMs
Jerry Va’vra’s focusing DIRC Tests Beam spot: s < 1mm Lead glass: • SLAC 10 GeV/c 2nd electrons • Beam enters bar at 90º angle • Prototype is movable to 7 beam positions along bar. • Time start from the LINAC RF signal, but correctable with a local START counter Local START time: s ~36ps Carsten Hast, SLAC, Test Beams in the US, October 2010, FNAL
Summary • We are excited to re-start ESA test beams! • - Unique High energy test beam line in the US, with plenty of infrastructures and SLAC support for Users • We install a short-term system for e-beams in ESTB with commissioning by the Summer • - 4 GeV full intensity or 13.6 GeV secondary e- beams down to 1 single particle/pulse • Installation of the full 4 kickers system by November • - First ESTB run in November / December • Beam parameters determined by LCLS. Availability 5Hz. Some opportunities to increase rate when not needed for LCLS. • Hadron beam line needs funding p p K e+ Mauro Pivi SLAC, ESTB 2011 Workshop
Additional availability: BYKIK “On” If LCLS experiments don’t need full 120 Hz rate, the remaining beam is parked out by BYKIK. Upstream of the LCLS undulator, BYKIK kicker is used to park the beam out of the beam line. A-line ESTB When BYKIK turns “ON”, the A-line kickers will also fire “ON” to re-direct the LCLS beam in ESTB
Number of pulses per hour parked on BYKIK dump in December, 2010. About ~5% additional availability to ESTB/ESA. Additional availability: BYKIK “On”
Short bunch length: development • Interest to short bunches (CLIC, accelerator R&D,etc) • LCLS ultra-short bunch length: 10 mm and smaller • In ESA, bunch length increases to 280 mm due to strong bends and large (optics) R56 • Possible to preserve ultra-short bunches in ESA with adequate $ support by interested parties … • With existing optics: 20-30 mm bunch length are possible if one manages to reduce R56 by a factor 3-4 and keep sE=0.02%. Presentation Title Page 36
Presentation Title Page 37