beam line characterization with the tofs1 demonstrating the emittance-momentum matrix mark rayner,...

Beam line characterization with the TOFs 1

Demonstrating the emittance-momentum matrixMark Rayner, CM26 California, 24 March 2010

3 6 10

140

200

240

Initial 4D N (mm)

Abs

orbe

r pz (

MeV

/c)

Cooling

channel

Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9DK sol D2D1

TOF1TOF0Target

Diffuser

GVA1 BPM1

,

1 2

Diffuser

t


Introduction Purpose of the beam line:

Generate the emittance-momentum matrix elements in pion muon decay beam lines

(3, 6, 10) mm (140, 200, 240) MeV/c

Data taking in December 6 mm – 200 MeV/c element

Runs 1380 – 1393, Kevin Tilley’s optics, 6k target pulses 6 mm – 140 MeV/c element

Runs 1409 – 1411, KT’s optics re-scaled to the new momentum, 2k target pulses

Phase space reconstruction by TOF0 and TOF1 Longitudinal momentum resolution O(5 MeV/c) Transverse position resolution O(2 cm) Transverse momentum resolution O(px

max/70)

Dependent on pxmax, the maximum un-scraped momentum of the optics in

question

Comparison with Monte Carlo simulations The 6-200 element has been simulated using G4BeamLine and G4MICE

This talk Reconstruction algorithm Distributions, means, covariance matrices, and emittances for 6-140 and 6-200 data

Analysis talk on Friday What this means for future stages in MICE


Selection of the muon peak

6-200

6-140

Intermediate

momentum


Reconstruction procedure

Estimate the momentum

p/E = S/t

Calculate the transfer matrix

Deduce (x’, y’) at TOF1 from (x, y) at TOF0

Deduce (x’, y’) at TOF0 from (x, y) at TOF1

Assume the path length S zTOF1 – zTOF0

s leff + F + D

Track through through each quad,

and calculate

Add up the total pathS = s7 + s8 + s9 + drifts

Q5 Q6 Q7 Q8 Q9

TOF1TOF0

zTOF1 – zTOF0 = 8 m


Momentum reconstruction: 6-200 simulation

Path length

!

Measuring path length removes the bias on the momentum measurement


Simulation/data comparison at TOF1 (6-200 matrix element)

This simulation uses the geometry from before TOF1

was moved z = – 16.7 cm = – 0.56 ns / c

Muon time of flight Muon momentum


6-140 (x, px, y, py, pz) in mm and MeV/c

4296-509.0 132.3-20.37 5.77 4451-5.34 1.32 168.8 15.13-438.7 55.8 -7.03 13.65 1286

30.08 -8.49 14.085 0.136 212.8

x RMS normalized phase emittance = 5.30 mmy RMS normalized phase emittance = 1.78 mmTransverse 4d RMS normalized phase emittance = 3.07 mm

Covariance matrix

Means


6-200 (x, px, y, py, pz) in mm and MeV/c

3359-610.0 205.818.99 -17.68 36001.17 -1.61 82.3 17.43-107.6 -5.0 -5.84 11.81 602

16.64 -12.09 15.311 -0.407 258.1

x RMS normalized phase emittance = 5.37 mmy RMS normalized phase emittance = 2.25 mmTransverse 4d RMS normalized phase emittance = 3.48 mm

Covariance matrix

Means


Momentum


Horizontal phase space

3 fit


Vertical phase space


Horizontal spatial dispersion


Horizontal momentum dispersion


Vertical spatial dispersion


Vertical momentum dispersion


Conclusion 6-200 element

Trace space beam properties required at TOF1 (6-200) <pz> = 261.8 MeV/c, x = 2.55 mm, y = 1.12 mm, and 4D N = 1.69 mm Takes into account binning effects

Trace space beam properties measured at TOF1 (6-200) <pz> = 258.1 MeV/c, x = 2.31 mm, y = 0.93 mm, and 4D N = 1.47 mm

Phase space beam properties measured at TOF1 (6-200) <pz> = 258.6 MeV/c, x = 5.37 mm, y = 2.25 mm, and 4D N = 3.48 mm

Phase space beam properties measured at TOF1 (6-140) <pz> = 212.8 MeV/c, x = 5.30 mm, y = 1.78 mm, and 4D N = 3.07 mm

Analysis talk on Friday Simulation: how would these beams behave in Stage 6? What about time?

Suggestion for the future data shifts Observe >40k muons (~6k target pulses?) for each of the nine

elements Kevin Tilley’s re-scaled 6-200 optics Optics derived from Marco’s genetic algorithm

beam line characterization with the tofs1 demonstrating the emittance-momentum matrix mark rayner,...

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