MICE Beamline Status

transcript

117 December 2009 MICE VC 127 1

MICE Beamline Statusm. apollonio

Goals of the BeamLine (and possible actions for improvement)

- Generate PIONS (TGT)- increase dip depth - maximise production / capture in 1st triplet

-Transport PI to DK solenoid- effects of varying DKSol current

- Capture Decay MUs (NB: backward == high purity)

- Transport MU to diffuser

- Match beam with (future) MICE lattice

Q5 Q6 Q7 Q8 Q9317 December 2009 MICE VC 127 3

Q1 Q3-Q2

F x (Q1-Q2-Q3)

Q1-2-3 scan (past run)

17 December 2009 4MICE VC 127

Upstream Beam-line

Target

ISIS synchrotron

• Q1-2-3 varied from nominal value

• Charged particles counted downstream of DKsolenoid

• Compared to MC – Charged – -, -, e-

• predict effect for single current changes

• verify in the next run

• DATA (Friday 13th 2009!)

nominal config.

charged-

Q1-Q2-Q3 scan – US beamline optimisation

nominal config.

f1-only (MC) DATA• Q1 scan

nominal config.

f2-only (MC) DATA

• Q2 scan

• Q3 scan

nominal config.

f3-only (MC) DATA

Muon BeamLine: G4BL simulation – Q1.DS + ------------ CALC_EMI ------------- + T= 0.196 mm rad x = 4.77 cm Y = 4.55 cm T = 38397 mm T = -7.105 RADIUS = 86.73 mm x= 0.2448 mm rad x = 32146 mm x= 9.68 x= 0.074 mm rad y= 0.1568 mm rad y = 45755 mm y= -32.9 y= 0.047 mm rad

P=444.71 MeV/c Z=Q1DS

X’ vs X Y’ vs Y

Y vs X

Muon BeamLine: G4BL simulation – TOF0

Y vs X P/P<10%

P/P|>10%

+ ------------ CALC_EMI ------------- + N= 2.91 mm rad X = 4.51 cm Y = 7.02 cm = 2874.8618 mm = 0.129 RADIUS = 91.4828342 mm x= 3.49 mm rad x= 1400.4 mm x= 0.489 eX=1.47 mm rad y= 2.43 mm rad y= 4867.7 mm y= -0.392 eY=1.02 mm rad

X’ vs X

Y’ vs Y

P=250 MeV/c Z=TOF0

Muon BeamLine: G4BL simulation – TOF1

+ ------------ CALC_EMI ------------- + N= 2.47 (mm rad) X = 5.9 (cm) Y = 4.37 (cm) T = 2334 (mm) T = 0.86 RADIUS = 75.9 (mm) x= 2.60 x= 2872 mm x= 1.598 y= 2.35 y= 1727 mm y= 0.039

P=223 MeV/c Z=TOF1

Y vs X P/P<10%

P/P|>10%

X’ vs X

Y’ vs Y

DKSol SCAN

- Rationale- Change DK current change optics downstream DKSol- handle for tuning- check data vs MC (our understanding of BL)- ongoing task (unfinished …)

DATA Run 1125 (PI+) Ptgt = 336.85 - PD2 = 330.9 MeV/c DKSol = 679A = 3.9T (+0.74T)

RUN 1125 DATA (DKSOl SCAN)

slab hits …

~8300 entries ~12000 entries

protons?

beam line- Rationale

- select u.s. of DKSol with D1- select d.s. of DKSol with D2

- back scattered muons == purity

DK solenoidQ2 Q3

Q5 Q6 Q7 Q8 Q9

d.s. BL tuning: match to diffuser

P=444 MeV/c

fix D1 fix D2

Optimising the BL – match to diffuserThis is the (e,P) matrix

http://mice.iit.edu/bl/MATRIX/index_mat.html 1717 December 2009 MICE VC 127

17 December 2009 MICE VC 127 18 190 350

Pdiff = 148 215 256

Ppi (tgt) = 350

Will it work?

RUN 1174-1177 – PI- (444MeV/c) MU- (256 MeV/c) at D2

NB: DTmu(256)= DTmu(300) * beta300/beta256 = 28.55 * .943/.923 = 29.13

0.943269

PI- should be here: 30.44

?RUN 1201 – PI- (336.8MeV/c) MU- (256 MeV/c) at D2

PI- should be here: 30.44

MU- should be the same asbefore … what is that?17 December 2009 21MICE VC 127

Not happy with this “optimized” lineFeel ONE Ppi for all cases not goodNeed a thought (== analysis of data)

I rescale the central (444 256) case for400.0 230336.8 200

Select backward going muons

Muon BeamLine: G4BL simulation – Diffuser

+ ------------ CALC_EMI ------------- + = 3.41 mm rad X = 4.35 cm Y = 4.88 cm T = 1250 mm T = -0.0017 RADIUS = 65.3 mm x= 3.76 mm rad x= 1004 mm x= 0.367 y= 3.10 mm rad y= 1534 mm y= -0.450

P=214 MeV/c Z=Diffuser

Measuring (e,P) from DATA

- Rationale- checking if an optics produces the foreseen () at diffuser- measure (and P) of the muon beam

- How?- use TOF0 / 1 as (x,y) stations- define muon sample- track mu’s in the Q7-8-9 triplet- infer x’, y’ (x,x’) (y,y’)

Mark Rayner’stools

a) Monitoring the Run

e.g. ... (7, 9, 10, … December)PI (444 MeV/c) MU (258 MeV/c)

beforenew calib

b) Select muons

c) Compute phase space

RUN 1408 – P0=400 /PD2=230 selecting the muons

-----------------------------------------------------------------------If muons...x RMS norm emittance = 4.5 mmy RMS norm emittance = 1.8 mmTransverse 4d RMS norm emittance = 2.8 mm

RUN 1386-1387 – P0=444 /PD2=256 selecting the muons

G4BL prediction

X’ vs X Y’ vs YG4BL

RUN 1409–1411 P0=336.8 /PD2=200 selecting the muons

(very broad peak, I kept conservative)

-------------------------------------------------------------------If muons...x RMS norm emittance = 4.27 mmy RMS norm emittance = 1.77 mmTransverse 4d RMS norm emittance = 2.75 mm

Conclusions- After 1 year we are back on DATA taking

- target is working- DKSol is ON

- We have been collecting data Since September 2009 - Calibrations - Rate vs Target Dip Depth (AD) - Q123 scan

- need to understand discrepancies

- DKSol scan- analysis in progress

- (e,P) matrix measurements- analysis just started, - Mark’s algorithm needs to be tuned

-(e,P) optimsed optics do not look handsome need to be understood and reviewed to some extent 17 December 2009 40MICE VC 127

Plans- Short term

- keep taking pi mu cases to increase statistics)- stick to (-) polarity to avoid rushing

- Medium Term (Shutdown)- campaign of measurements of mag fields ? - hysteresis checks (doc is not clear + measurements done at I<Imax)- any other suggestion?

- Longer term (>next User’s Run)- review optimisation of the (e,P) matrix- back to (+) polarity and repeat (e,P) data taking

MICE Beamline Status

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