Run5 Analysis of RHIC-pC Polarimeter

RIKEN/RBRC

Itaru Nakagawa

Sept. 30, 2006

Contents Kinematics Reconstruction

source energy calibration Deadlayer energy correction Systematic error estimation(1)

Polarization (1st Path Analysis Results) Online/Offline Event selection 2/3 Strip by strip consistency sin() fit Systematic error estimation (2)

400keV

5.5MeV

Am Source Energy Calibration

Eloss(entrance window) = Eloss(foil) = Eloss(10-6 Vacuum) = 0

Ealpha = 5.486MeV

5.486 MeV (85%)

5.443 MeV (12%)

Other (<2%)

100% linearity of Attenuator

100% linearity of ADC

Linear Si Response w.r.t Depth

Fitting Error < 0.01%

~50keV/tic

Systematic Error is Negligible

Energy Correction (Stability)

Stability Error9 ~ 11 g/cm2

Stability Error9 ~ 11 g/cm2

Energy Correction (Strip by Strip Consistency)

Strip Number （７２ Total ）

Ene

rgy

Cor

rect

ion(g

/cm

2 )

•All Detectors are made from same wafers Any inconsistency should be accounted as sys

Energy Correction (Strip by Strip Consistency)

Systematic Error Summary(1)

Blue Yellow

Energy Calibration --- ---

strip-by-strip consistency

3.5 (1) 4.5 (2)

Event Selection 3 3

Stability 9.0 11.1

Total 10.1 (9.1) 12.3 (11.3)Ene

rgy

Cor

rect

ion

[ug/cm2]

( ):Relative Error

Online/Offline Polarization

AN(24GeV) AN(100GeV)AN(24GeV) AN(100GeV)

Event Selection Dependence

2 vs 3 Cut Consistency Systematic Error

2

3

Event Selection Error

Event Selection Error ~ 1%( was 3% in Run3,4)

Event Selection Error ~ 1%( was 3% in Run3,4)

€

δ a /b( ) = (a /b) (δa /a)2 − (δb /b)2

Strip by Strip Consistency ~ sin() fit ~

Azimuthal Angle Distribution

Strip by Strip Consistency Error

2 Distribution of sin() fit Well Distributed around 1 Evidence of Consistent Polarization Measurements by individ

ual strips No systematic error allocated

Systematic Error Estimate

Blue Yellow

Energy Scale 3% 4%

Event Selection 1% 1%

Polarization Profile

Normalization from Run4

8.5% 8.5%

Total 9% 9.5%This systematic error estimation is estimated based on Run4 Normalization

Road Map to Finalize the Analysis

Remaining Major Items Continue QA

Suspicious bunch, strips Study Off-Centered Target Measurements

Fill by Fill Analysis Polarization Profile

Normalization with Jet