rhic polarimetery

17
RHIC Polarimetery A.Bazilevsky for RHIC Polarimetry group RHIC Spin Collaboration Metting May 1 (Friday), 2009

Upload: bethan

Post on 27-Jan-2016

40 views

Category:

Documents


0 download

DESCRIPTION

RHIC Polarimetery. A.Bazilevsky for RHIC Polarimetry group RHIC Spin Collaboration Metting May 1 (Friday), 2009. pC: s=2 00 GeV run. The same setup as in the end of s=500 GeV run Energy Calibration Energy and ToF corrections Targets The same measurement strategy - PowerPoint PPT Presentation

TRANSCRIPT

Page 1: RHIC Polarimetery

RHIC Polarimetery

A.Bazilevsky for RHIC Polarimetry group

RHIC Spin Collaboration MettingMay 1 (Friday), 2009

Page 2: RHIC Polarimetery

pC: s=200 GeV run

The same setup as in the end of s=500 GeV runEnergy CalibrationEnergy and ToF correctionsTargets

The same measurement strategyRun all 4 polarimeters simultaneously (vertical and horizontal scans for each beam) Monitor the system (excluding detectors) during measurements with generator pulses

So far no major issues

Page 3: RHIC Polarimetery

pC Rate historys=200 GeV

Smooth, no change

Page 4: RHIC Polarimetery

pC measurements

Fills 10616 (Apr 18) – 10682 (Apr 30)

“Online” polarizations: 0.50-0.60

“Quite” consistent (relative) behavior of Pol-1 vs Pol-2

Pol-1 measure slightly lower than Pol-2: by ~5%

Online Polarization (%), not normalized (!) vs fill

Page 5: RHIC Polarimetery

pC-Blue vs HJet

Hjet/pC is stable over fills within (large) stat. errors (of HJet)

HJet: <P>=54%(fills 10616-10668)

HJet/Blue1 1.03

HJet/Blue2 0.97

Page 6: RHIC Polarimetery

pC-Yellow vs HJet

Hjet/pC is stable over fills within (large) stat. errors (of HJet)

HJet: <P>=56%(fills 10616-10646)

HJet/Yell1 1.05

HJet/Yell2 1.01

Page 7: RHIC Polarimetery

More precise Hjet-pC comparison

Hjet: fills combined in 3 periods

Drop in polarization confirmed by Hjet in both blue and yellow

pC-yellowHJet

pC-blueHJet

Page 8: RHIC Polarimetery

Pol. Profile 2

2

P

IR

Polarimeters 2Polarimeters 1

Usual…R0.15 in previous years (100 GeV beams)R0.1 Experiments see 5% more polarization than Hjet

Horizontal profile

Vertical profile

Vertical profile

Horizontal profile

Page 9: RHIC Polarimetery

Spin Horizontal Components=200 GeV

Horiz. Component:

0.065 (of ~0.55) ~7 degrees

0.035 (of ~0.55) ~3.5 degrees

Consistent between Pol-1 and Pol-2

Page 10: RHIC Polarimetery

Spin Horizontal Components=500 GeV

No spin horizontal component with 250 GeV beams

Page 11: RHIC Polarimetery

Backups

Page 12: RHIC Polarimetery

Rate historys=500 GeV

Page 13: RHIC Polarimetery

C Mass

Page 14: RHIC Polarimetery

pC: Polarization Profile

pC Scan C target over the beam cross:

Target Position

Inte

nsity

Pola

rizati

on

2

2

P

IR

I

P

2. Obtain R directly from the P(I) fit:

2

2

max 2exp)(

P

xPxP

2

2

max 2exp)(

I

xIxI

R

L

LPP

maxmax

P

I

Precise target positioning is NOT necessary

1. Directly measure I and P :

R=0.290.07

Page 15: RHIC Polarimetery

pC Monitoring

Generator pulses

Carbon

Ekin

ToF

Page 16: RHIC Polarimetery

pC monitoringLow rate example: 10429.013 High rate example: 10346.007

Pulse ToF vs time

Event rate vs time

Pulse rate vs time

Pulse amplitude vs time

Page 17: RHIC Polarimetery

AN vs energy

Ebeam = 100 GeVEbeam = 100 GeV

Any shift in energy measurements lead to a shift in AN (asymmetry)