Beam direction and flux measured by MUMONK. Matsuoka (Kyoto)for the MUMON group

Contents:1.Horn focusing effect2.Beam stability (direction/flux)3.Beam scan on target4.Absolute beam flux and comparison w/ MC

Neutrino beam directionMeasure () beam direction by measuring muon profile center. (Another end is target)1-mrad shift of the beam direction corresponds to 11.8-cm shift of the MUMON profile center.Requirement for MUMON:

3-cm=0.3mrad precision2.5˚

Beam dump

MUMON295 kmTarget

Hornsp

118 m

OTR

Baffle

Basic Analysis methodanalysis has done by simple charge integration& 2D Gaussian fitting.for both online/offline analysis

PedestalGate

Silicon80 mV

for 3 x 1011 ppp

wave form x 49

in some analysis,we also use total charge of 49 ch

Confirmation of Horn focusing

3 horns, 320 kA (shot# 47577), 2.16 x 1012 ppb, 6 bunch1st horn, 275 kA (shot# 47987), 2.10 x 1012 ppb, 6 bunchno horn, 0 kA (shot# 48704), 2.13 x 1012 ppb, 6 bunch

peak sigma peak sigma1547 pC 83 cm 38.5 pC 90 cm467 pC 95 cm 13.2 pC 104 cm218 pC 110 cm 6.29 pC 126 cmx2.1

x7.1

Stability of the beam direction

Monitor the profile center obtained by the 2D Gaussian fit. During continuous 425 shots (Run:

280136) With 3 horns operation at 320 kA. Proton beam intensity (CT05):

2.15 x 1012 ppb x 6 bunches

* 30-dB attenuators was used for the silicons.

stability (center position)Si, X center IC, X center

RMS = 2.9 mm

RMS = 4.3 mm

Si, Y center IC, Y center

RMS = 1.8 mmRMS = 2.3 mm

Center values are different by ~1cm.Need check!

center position fluctuationSi X : 2.9 mm (1.2 mm from Si noise)

2.6 mm from beam ? Y : 1.8 mm (1.1 mm from Si noise) 1.4 mm from beam ?

IC X : 4.3 mm (3.1 mm from IC noise) 3.0 mm from beam ? Y : 2.3 mm (1.6 mm from IC noise) 1.7 mm from beam ?

Stability (beam direction) (MUMON center)/(Dist.from target)

• No time dependent drift• Beam direction was tuned well within 1

mrad.Monitor alignment should be checked.Further turning in Jan.

Beam axis√ (x

2 + y

2 )

Stability (flux)incl. stability of beam+horn field+MUMON

Silicon Chamber

RMS/Mean: 0.8% RMS/Mean: 0.8%

stability (flux) CT normalized

stability : 0.5% RMS CT stability : 0.5% (from Shibata-san’s talk) MUMON measurement error : 0.06 % (Si) & 0.14 % (IC)

(estimated from pedestal RMS of this RUN) consistent with CT stability

RMS : 0.5 % RMS : 0.5 %

Si / IC stability

RMS = 0.18 % consistent with estimated measurement error

( 0.06%(Si) + 0.14%(IC) = 0.15% )

RMS : 0.18 %

Stability (flux) incl. beam+horn field+MUMON

No time dependent drift

Beam scan on targetOnly horn-off data in Nov/Dec commissioning(1st horn 273kA data in April/May

commissioning)Scan w/ all horns will be in Jan/Feb. Opposite direction shift is expected.

x

target

Proton beam were intended to shift in parallel. But angle change also existed

Beam scan on target- Center position-

•MUMON alignment?• Beam angle effect? (0.3mrad)• Target alignment?• SSEM18-19 alignment?

Beam scan on target-Muon yield-

Total Charge Peak charge

Gap btw. Baffle and target?

P beam30mm

26mm

baffle

target

Target center may be at -0.5~-1mm??

Absolute muon flux estimation

Two methods in addition to the emulsion measurement A) Energy deposit calculation by MC.

Get the relation btw. muon flux and energy deposit in the detector

B) Calibration by electron beam testUnder study. Preliminary result is showing

consistent result w/ A)

Estimation from MC energy deposit

Energy deposit by all particles is summed up and divided by #muonsContrib. from -rays generated outside detector and

escape of -rays generated inside detector are (automatically) taken into account

Edep = 2420 MeV/(15266 muons) = 158.5 keV/muon

Ionization yield:Q = Edep / 3.6 eV x e0

= =7.045 x 10–3 pC/muon

2420 MeV

Energy deposition in the silicon (MC)

*Relying on estimation of -ray contribution by Geant3.Bare Si measurement confirmed that the -ray contribution is robust(~1% effect) against materials around.

Data x: 95.0 cmMC x: 107.7±1.3 cm

1st horn 273 kA

Data x: 120.4 cmMC x: 127.9±3.7 cm

Horn 0 kA

Data x: 69.7 cmMC x: 84.6±0.6 cm

3 horns 320 kA Spill 332358

Spill 621503Spill 622787

Comparison w/ MC (slice histogram)

0kA 1st Horn 273kA

3Horns 320kA

Data/MC

0.6 0.7 0.9Error is still under study.

Profile comparisonData / MC (09c with emulsion shots)

19

273kA

220kA

0kA

data

MC

SummaryHorn focusing effectBeam direction

Tuned within 1 mrad (and will be further tuned.) Less than 0.03mrad (rms) fluctuation

Beam flux <0.5% (RMS) fluctuation (maybe 0.06%)

Target scanHorn-off data for target center determination

Need more study to understand the obtained resultsHorn-on data will be taken in Jan./Feb.

Absolute muon flux estimations and comparison w/ MCAgree with the emulsion measurement.

Supplement

Stability of the proton beam

Run: 280136Cont. 6-bunch operationInc. monitor stability Stability of CT: 0.5%

(Shibata-san’s talk)RMS: 0.1 mm

RMS: 0.2 mm

RMS/Mean: 0.9%

total charge error estimation 1

integrate 37 bins from gate start (1-bunch length) & sum up 49 ch

off-center mean due to slow component of the signal

RMS 172.6 pC RMS 11.25 pC

total charge error estimation 2

Si 172.6 pC / 764.8 nC x √6 = 0.055 % RMSIC 11.25 pC / 19.8 nC x √6 = 0.139 % RMS

pedestal RMS (1bunch) / total charge x 6 bunch

Uji electron beam test6-coil CT Electronics calibration factor inc. AMP:

(4.053±0.004) x 10–3 pC/ADC Pedestal RMS: 17.9 (for 120 samples)

0.007 pC uncertaintyIC Electronics calibration factor:

(4.158±0.002) x 10–2 pC/ADC

Energy loss comparison (Uji/T2K)

Energy loss in the chamber (Ar + 2% N2, 131 kPa, 34˚C) by MC

Uji 100-MeV electron beam: 4.042 keV/electron (av. of all particles; , e)

T2K beam at the center: 4.755/4.824/4.443 keV/muon (1st horn 0/220/273 kA) 4.674 ± 0.231 keV/muon (av. of all particles; , e, )

Uji beam T2K beam

A-1. Chamber calibrationCT gain was calibrated by Suzuki-san 0.1555 ± 0.0001 (out/input charge)

IC/CT from the Uji electron beam testCorrection of energy loss diff. between the electron beam and the T2K muon beam (16%).

IC calibration factor:(4.80±0.25) x 103 muon/cm2/pC

IC/CT = 128.0±0.2

A-2. Silicon calibrationSi/IC ratio from high intensity beam data (horn off) --- 33.89±0.09Correction of the z-position difference (8%)

Beam density at each position is different due to beam divergence.

Silicon calibration factor: 154±9 muon/cm2/pC

Absolute muon flux (chamber)

CT efficiency by calibration: 0.1555 ± 0.0001 CT factor: (4.019±0.003) x 107 particle/pCIC/CT (Uji): 128.0±0.2 (Ar + 2% N2, 130 kPa, 29.7˚C) Uji IC factor: (3.140±0.006) x 105 electron/pC (3.120±0.006) x 105 electron/pC @ 131 kPa, 34˚CEnergy loss in MC (Ar + 2% N2, 131 kPa, 34˚C)

Uji 100-MeV electron beam: 4.042 keV/electron (av. of all particles; , e)

T2K beam at the center: 4.674±0.231 keV/muon (av. of all particles; , e, )

T2K IC factor (“collected charge” to “muon flux” conversion): (2.70±0.14) x 105 muon/pC = (4.80±0.25) x 103 muon/cm2/pC

Absolute muon flux (silicon - Si/IC)

T2K IC factor: (4.80±0.25) x 103 muon/cm2/pCCharge ratio at the center Si/IC in data (run 280086, horn 0 kA): 33.89±0.09 (–15 dB Att. is not calibrated, assuming 0.1777)

Beam size: x,ySi 128.8±0.1, 138.1±0.1, x,y

IC 133.6±0.6, 155.4±0.4 cm

Muon flux ratio at the center of Si/IC plane in MC 1st horn 0 kA: 1.066±0.017sta (x,y

Si 170±4, 166±4, x,yIC 174±5, 177±5 cm)

1st horn 220 kA: 1.072±0.015sta (x,ySi 157±3, 162±3,x,y

IC 161±3, 182±5 cm) 1st horn 273 kA: 1.084±0.013sta (x,y

Si 128±2, 125±2,x,yIC 133±2, 139±2 cm)

1.084±0.018±0.013sta

Si factor: 4.80 x 103 / (33.89 / 1.084) = 154±9 muon/cm2/pC

Absolute muon flux (silicon - dE/dx)

MC estimation of energy deposit in the silicon plane at the center with 1st horn 273 kA:Eloss = 2.420 GeV/(15266 muon) = 158.5

keV/muonIonization yield:Q = Eloss / 3.6 eV x e0 = 7.045 x 10–3 pC/muon Si factor: 141.9 muon/pC

Comparison between Si and emulsion

Muon flux ratio at the center of Si/emulsion plane in MC 1st horn 0 kA: 1.096±0.018sta (x,y

Si 170±4, 166±4, x,yIC 177±5, 183±5 cm)

1st horn 220 kA: 1.113±0.016sta (x,ySi 157±3, 162±3,x,y

IC 165±4, 188±5 cm) 1st horn 273 kA: 1.128±0.014sta (x,y

Si 128±2, 125±2,x,yIC 136±2, 145±2 cm)

1.128±0.032±0.014sta

Muon reduction rate at Si by the cut for the emulsion analysis (momentum > 0.05 GeV/c, angle < 0.3 rad) by MC

1st horn 0 kA: momentum cut 0.024%, angle cut 2.1% 1st horn 220 kA: momentum cut 0.026%, angle cut 3.4% 1st horn 273 kA: momentum cut 0.052%, angle cut 3.6±1.2sta % 3.65±1.5±1.2sta %

Absolute flux (summary table)

Silicon (Si/IC) Silicon (dE/dx) Emulsion jnubeam 10a1st horn 0 kA 1.04±0.07 0.96 1.00±0.02 1.74±0.021st horn 220 kA

1.70±0.12 1.56 1.61±0.02 2.37±0.02

1st horn 273 kA

2.30±0.16 2.12 2.16±0.03 3.07±0.02

Muon flux measured by each detector at the center emulsion (104/cm2)

Silicon (Si/IC) Silicon (dE/dx) Emulsion1st horn 0 kA 0.60 0.55 0.571st horn 220 kA

0.72 0.66 0.68

1st horn 273 kA

0.75 0.69 0.70

Muon flux ratio of each detector to MC

Absolute muon beam flux

Silicon (chamber) measurement is consistent w/ emulsion one.

Muon flux measured by each detector at the center emulsion (104/cm2) • Correction of the z-

position diff. is applied.• Cuts for emulsion

analysis is applied (p > 0.05 GeV/c, < 0.3 rad)

@ 3.7 x 1011 ppb

[ 3 horns 320 kA ]IC data/MC: 0.87