MICE tracker meeting 2005.3

Prototype TOF test for tracker test @ KEK

Osaka universityAtsushi Horikoshi

contents magnetic field of Super Jacee shape of TOF timing resolution test @KEK-PS pi2 Analysis calibration for PhaseⅡ

PhaseⅡsetup (KEK-PS pi2)

perpose measurement of momentum emittance reconstruction

super conducting magnetSuper JACEE , 1T

2.1m

φ８５０mm

vessel for ballonexperiment

front veiw

side view

requirement of TOF π/μ PID

3σresolution momentum scan

measurement of absolute value resolution of momentum

keep high timing resolution in magnetic field

π/μPID momentum of Phase Ⅱ

300 ～ 600Mev/c timing resolution f

or 3σPID upstream 50ps down strean 50ps

3σPID

momentum timing resolution

upstream 50ps downstream 50ps

momentum resolution p<600MeV Δp/p<5.6%

7

00.25 0.6

shape of TOF to avoid reduction of timing resolution

fine mesh PMT (used BESS experiment) R6504S (hamamatsu, 19DY)

PMT is parallel to magnetic field long light guide

magnetic field 1500Gauss ,almost parallel satisfies the condition

コイル

effect of the ground of iron@PMT

1T

thanks for Arimoto san

TOSCA

magnetic field of PMT the effect of iron

is small

iron

y

0

geometry

magnetic filed first second third

prototype test（ KEK-PS pi2,2005 Feb）

guide7 simulation timing resolution47ps

setup of beamline

analysis

ref2)}(ref1σ

ref2)(tofσ

ref1)(tof{σ

(tof)σ

2

2

2

2

1

2

σ(tof-ref1) =64ps

⇒σ （ tof ） =49ps

position scan,timing resolution

timing resolution[ ｐｓ ]

●： PMTR〇： PMTL

under　●weightedmean

distance from center[ ｃｍ ]

90

timing resolution is 50ps @ all position

50

0

0 2020

satisfied condition of PID

position scan 2 , npe npe

600~800 very high npe

attenuation length 118cm

effective velocity

Veff=15.3cm/ns not good linearity

calibration for PhaseⅡ we can’t determine hit position from ext

ernal tracker in PhaseⅡ calculation from tdc mean Veff=15.3cm/ns

t(hitR)=tr-(20-z)/Veff t(hitL)=tl-(20-z)/Veff z=(tr-tl)xVeff/2

timing resolution using tdc mean

position is calculated from tdc , tofrt-toflt

timing resoluiton 50~57ps 48~52ps (using ref1 positio

n) position spread

-0.5~0.4cm

summary timing resolution

50ps @ all position npe=600~800 Veff=15.3cm/ns

calibration using tdc mean 53ps @ all position , stability is not good