1 of 29 lcws’06, march 2006t. markiewicz for m. woods, slac lcws’06 bangalore march 12, 2006

1 of 29T. Markiewicz for M. Woods, SLAC LCWS’06, March 2006

http://www-project.slac.stanford.edu/ilc/testfac/ESA/esa.html

LCWS’06 BangaloreMarch 12, 2006

CCLRC LLNL QMUL U. of Bristol UMass Amherst

CERN Lancaster U. SLAC UC Berkeley U. of Oregon

DESY Manchester U. TEMF TU Darmstadt U. of Cambridge

KEK Notre Dame U. U. of Birmingham UCL

Collimator design, wakefields (T-480)BPM energy spectrometer (T-474)Synch Stripe energy spectrometer (T-475)IP BPMs/kickers—background studiesEMI (electro-magnetic interference)

PAC05 paper/poster: SLAC-PUB-11180, e-Print Archive: physics/0505171

ILC Beam Tests in End Station AILC Beam Tests in End Station A


Beam Parameters at SLAC ESA and ILCBeam Parameters at SLAC ESA and ILC

Parameter SLAC ESA ILC-500

Repetition Rate 10 Hz 5 Hz

Energy 28.5 GeV 250 GeV

Bunch Charge 2.0 x 1010 2.0 x 1010

Bunch Length 300 m 300 m

Energy Spread 0.2% 0.1%

Bunches per train 1 (2*) 2820

Microbunch spacing - (20-400ns*) 337 ns

*possible, using undamped beam


SummarySummary

Funding from:i) SLAC ILC group, ii) UK, iii) DOE LCRD

3 test beam experiments have been approved: T-474, T-475, T-480

Commissioning Run January 4-9~20 people taking shifts (including 4 grad students) from SLAC, UC Berkeley, Notre Dame, U. of Oregon, UC London, Daresbury Lab

2006 Running schedule:ii) April 24 – May 8, 2006iii) July 3-17, 2006

T-474, T-475, T-480 and Bunch Length measurements in both periodsFONT-ESA & EMI testing in July

Plan for two 2-week runs in FY07


ESA Equipment Layout: ESA Equipment Layout: Now & FutureNow & Future

18 feet

BPMs used to commission BPM electronics Ceramic gap bunch length monitors w/ 3 rf readoutsOregon quartz fiber detector

Dipoles + Wiggler

Wakefield box Wire Scanners FONT-ESA BPM-Triplets

Collimator

Support Girders

black=nowblue=March’06green=July’06red=later

Upstream:


Alcove rf BPMs(3 sets of bpm processors

to analyze data) 100GHz Bunch Length Detector

Hardware installed during January Hardware installed during January 2006 Commissioning Run2006 Commissioning Run


Collimator wakefield box

Wire Scanner

Hardware installed during January Hardware installed during January 2006 Commissioning Run2006 Commissioning Run


Precision energy measurements to 50-200 parts per million are needed for Higgs boson and top quark mass measurements. BPM (T-474) and synchrotron stripe (T-475) spectrometers will both be evaluated in a common 4-magnet chicane. These studies address achieving the ILC precision measurement goals: resolution, stabilty & systematics

T-474, 475: T-474, 475: Energy SpectrometersEnergy Spectrometers


T-474 and T-475T-474 and T-475

T-474 BPM Energy Spectrometer:PIs: Mike Hildreth (U. of Notre Dame) & Stewart Boogert (RHUL,UK)Collaborating Institutions: U. of Cambridge, Royal Holloway, SLAC, UC Berkeley, UC London, U. of Notre Dame

T-475 Synchrotron Stripe Energy Spectrometer:PI: Eric Torrence (U. of Oregon)Collaborating Institutions: SLAC, U. of Oregon

Prototype quartz fiber detector:8 100-micron fibers + 8 600-micron fibers w/ multi-anode PMT readout


Collimators remove beam halo, but excite wakefields.Goal is to determine optimal collimator material and geometry. These studies address achieving theILC design luminosity.

T-480: Collimator WakefieldsT-480: Collimator WakefieldsApril, July 2006 runsApril, July 2006 runs

PIs: Steve Molloy (SLAC), (Steve replaces PT), Nigel Watson (U. of Birmingham, UK)Collaborating Institutions: U. of Birmingham, CCLRC-ASTeC + engineering, CERN, DESY, Manchester U., Lancaster U., SLAC, TEMF TU

=298mrad

=168mrad

r1 =3.8mm

r2 =1.4mm

4

1=/2 rad

2=168mrad

r1=3.8mm

r2=1.4mm

3

168mrad

r=1.4mm2

=/2rad

r=1.4mm1

Beam viewSide viewSlot

h=38 mm

38 m

m

7 mm

208mm

28mm

159mm

Collimator wakefield box installed in ESA.2 sandwiches, each holding 4 collimators, available.Collimators being provided by UK groups.Wakefield kick angle measurements provided by T-474 BPMs.


January 2006 Commissioning RunJanuary 2006 Commissioning Run

1. Infrastructure: • DAQ (both SCP and experimental—evolution from E-166)• Wire scanner for spotsize, emittance measurements• simple bunch length diagnostics w/ 3 rf detectors (10, 20 and 100 GHz)• Energy spread measurements with A-line synch lite monitor (SLM)• A-line commissioning for single bunch, low emittance beams→ full characterization of beam’s 6-dim phase space

2. T-474: BPM Energy spectrometer commissioning - new BPM electronics developed at UC Berkeley using existing rf bpms;

SIS waveform digitizers provided by UK

3. T-475: Synch. Stripe energy spectrometer- testing Oregon quartz fiber detector at A-Line SLM location

4. T-480: Collimator Wakefield Measurements, • commissioning ASSET collimator wakefield box; get beam cleanly

thru 4mm gap and take beam-based alignment data


Oregon quartz fiber detector at A-line SLM locationfor T-475

DAQ Control at Counting House

January 2006 Commissioning RunJanuary 2006 Commissioning Run

e- beam

SR photons


DAQ Screens


LiTrack simulation for LiTrack simulation for achieving ILC parameters in ESAachieving ILC parameters in ESA

Bunch charge (1E10) 2.0DR bunch length (mm) 6.0DR energy spread (%) 0.074RTL Voltage (MV) 38RF phase 2-6 (deg) -10RF phase 10-20 (deg) -17.5Aline R56 (m) 00.465Aline T566 (m) 2.744

E/E=0.2%

z=300um


Bunch Length Measurements in Bunch Length Measurements in January 2006 Commissioning RunJanuary 2006 Commissioning Run

2-d scan versus Linac injection phase and compressor voltage

Peak in 100 GHz signal

as Linac Injector Phase &

Compressor voltage

scanned, at lower

frequencies signal

correlates with intensity

only

100GHz 20GHz

10GHz Intensity


Energy profile with SLM digitized(saturates at peak)

1.2% E/E

117-micron vertical spot

Beat Size and Energy Spread in Beat Size and Energy Spread in January 2006 Commissioning RunJanuary 2006 Commissioning Run

Energy profile with SLM digitized(saturates at peak)

1.2% E/E

Nominal setup had low energy tail. Optimizing Linac injection phase and compressor voltage for short buncheseliminates low energy tail and gives high energy tail.

Wire scanner measurement of vertical spotsize.


Beam Emittance in A Line in Beam Emittance in A Line in January Commissioning RunJanuary Commissioning Run

Linac emittance with S28 wires

Q28 and wire scans for measuringhorizontal, vertical emittance in ESA

y ~ 4.0 e-05 ??x ~ 31. e-05 OK

• expect ~4x emittance growth in A-line due to synch. radiationand chromatic aberrations

• data was taken with wrong magnet config for A-line orbitand dispersion matching (→increased y-emittance?)

• vacuum problem at start of A-line may also increase y-emittance


BPM Electronics Commissioning BPM Electronics Commissioning during January 2006 Runduring January 2006 Run

T-474 commissioning results using new bpm processors to downmix signals to 70MHz and digitize with SIS waveform digitizers at 100MHz.

~5-micron bpm resolution achieved so far. Expect <1-micron resolution, so studying contributions from phase noise, angle jitter, fitting procedure …


T-474 plans for T-474 plans for April, July runsApril, July runs

For April install two spear girders with 2nd wire scanner and 2 new BPM triplets:– ILC Linac prototype BPMs being developed by C. Adolphsen, G.

Bowden, Z. Li (Location=3BPM3-5)– E158 ASSET BPMs (Location=3BPM9-11)– Future: new BPMs will be designed at UC London in collab. with SLAC

For July install interferometer for ILC Linac bpms


Continued Plans for Continued Plans for April, July RunsApril, July Runs

• T-475T-475– continue studies with prototype detector at A-

line SLM location• need access to snip 1 or 2 fibers to provide for

background measurements and to increase gain on differential line driver

• T-480T-480– Wakefield study using T-474 BPMs


New Studies for New Studies for April, July RunsApril, July Runs

• Bunch Length StudiesBunch Length Studies– add 2nd 100GHz diode w/ WR10 waveguide (noise,

resolution, stability…)– partner with LCLS for bunch length studies in 100-500

micron range w/higher frequency detectors• (M. Ross, P. Emma, D. McCormick, S. Walston, …)

• EMI StudiesEMI Studies– Characterize EMI along ESA beamline using antennas

& fast 2.5GHz scope– Measure dependence on bunch charge, bunch length

• US-Japan funds for FY06 available– KEK—Y. Sugimoto, SLAC--G. Bower


• Feedback BPM survivability tests (Oxford U.):• Approximate rule of thumb:

– 1 pm error in BPM processor per charge absorbed or knocked out of strip

• Irradiate BPM in realistic environment, study:– noise on direct beam signals– long-term BPM stability and performance

• Also, plan to do detailed EM modelling of BPM to simulate the effect of backgrounds on performance

FONT@ESA: FONT@ESA: July RunJuly Run


Feedback BPM Hit Dependence on Machine Parameter Set

High LumiScheme14

Low PScheme13

Large YScheme12

Low QScheme11

NominalScheme10

USSCScheme9

1 TeV TESLA

Scheme 8

High LumiScheme7

Low PScheme6

Large YScheme5

Low QScheme4

NominalScheme3

USSCScheme2

500 GeV TESLA

Scheme 1# pairs hitting FB BPM

0

10000

20000

30000

40000

50000

S1 S2 S3 S4 S5 S6 S7 S8 S9 S10 S11 S12 S13 S14 S14n

scheme

hits

2mrad 20mrad93443


Pairs Simulated at ESA w/ Spray Beam

• Reproduce the pair backgrounds predicted in the IR at ESA by firing 30 GeV beam into a fixed-target ‘radiator’ – 2 radiator options:

• Thick target in Beam Switch Yard (BSY)• Thin target in ESA

Output of simulation shows range of energies between 0 and 30GeV


Mechanical mock-up of forward material in the ILC IR

BeamCal plus BPM and QD0 Mechanical Substitute

–Quartz Cerenkov on mover to monitor pair flux–removable Pb glass block for normalization–Beamcal/BPM Mockup


Other Tests Under DiscussionOther Tests Under Discussion

1. Other BPM test stations

2. More Bunch length and longitudinal profile measurements (for LCLS)• electro-optic, Smith-Purcell, coherent transition radiation, other?

• Initial measurements are using rf detectors at a ceramic gap in a few frequency bands from 10GHz-100GHz

• 300-micron ILC bunch length is same as LCLS after 1st bunch compressor• ESA is a good place to commission diagnostics for this

3. Spray beam or fixed target to mimic pairs, beamsstrahlung, disrupted beam for testing synchrotron stripe energy spectrometer or BEAMCAL

4. IR Mockup?• Mimick beamline geometry at IP within ±5 meters in z and ±20 cm radially

5. Single Particles (electrons, photons, pions) 1-25 GeV particles with 1 or less particles/bunch at 10Hz for ILC Detector tests


ESA has now been revalidated for using primary beams. A major consideration was reviewing radiation physics requirements and the ESA PPS (personnel protection system).

The ESA PPS does not meet modern standards for redundancy of sub-system components. Additionally, system components are old and some are past their rated service life.

The cost estimate for replacing the ESA PPSIs $500K

Will be requesting to run with the existing PPS thru the end of FY08 (end of PEP-II era). ESA

running beyond that would require a new PPS.

Safety Reviews & PPSSafety Reviews & PPSRelevant for post 2007 runsRelevant for post 2007 runs


ESA Beam Tests in LCLS Era?ESA Beam Tests in LCLS Era?

The ESA program is NOT compatible with LCLS without effort– Some initial discussions with SLAC management have begun

LCLS will use last 1/3 of SLAC Linac: 14 GeV beam, 1 nC, 120 Hz

•controls issues•low bunch charge w/ LCLS gun specs•pulsed magnets to share LCLS beam•Would need PPS upgrade


ILC at SABER?South Arc Beam Exp. Region

•Need to run front 2/3 of linac ($)•Separate bypass line•Separate pulse compressor


SummarySummary

We have a strong collaboration for important ILC beam tests, addressing ILC luminosity and ILC precision

Strong support from SLAC’s ILC group, UK collaborators and others

3 test beam experiments have been approved and are in progress; additional ones are in preparation or under study

Successful 5-day commissioning run earlier this month; 2 additional runs scheduled before end of July. Plans to continue into FY07 andFY08, parasitic with PEP-II operation.

1 of 29 lcws’06, march 2006t. markiewicz for m. woods, slac lcws’06 bangalore march 12, 2006

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