Presentation is loading. Please wait.

Presentation is loading. Please wait.

RHIC pC Polarimeters in Run9: Performance and Issues A.Bazilevsky for the RHIC CNI Group Polarimetry Worshop BNL, July 31, 2009.

Published byRoland Newton Modified over 8 years ago

Similar presentations

Presentation on theme: "RHIC pC Polarimeters in Run9: Performance and Issues A.Bazilevsky for the RHIC CNI Group Polarimetry Worshop BNL, July 31, 2009."— Presentation transcript:

1 RHIC pC Polarimeters in Run9: Performance and Issues A.Bazilevsky for the RHIC CNI Group Polarimetry Worshop BNL, July 31, 2009

2 pC: goals/strategy Polarization measurements for experiments Target Scan mode Provides polarization at beam center, polarization profile, average polarization over profile 10-30 sec per measurement For stat. precision 2-3% 4-5 measurements per fill, per ring Controls polarization decay vs time in a fill Polarization profile, both vertical and horizontal Normalized to HJet measurements over many fills Knowledge on polarization profile in one transverse direction is required Fill-by-fill polarization Knowledge on polarization profile in both transverse directions is required Feedback for accelerator experts Beam emittance measurements, bunch-by-bunch Polarization Polarization profile, both vertical and horizontal Polarization at injection (and polarization loss in transfer) Polarization on the ramp (and polarization loss during ramp) Ultra thin Carbon ribbon Target (5  g/cm 2 )1 3 4 5 6 2 Si strip detectors (TOF, E C ) 18cm

3 pC in Run9 Two independent polarimeters in each ring (but using the same DAQ) 12 carbon targets in each polarimeter (6 vertical and 6 horizontal) 6 detectors in each polarimeter 3 types of detectors: “BNL strip”: 12 strip in each detector Test Detector1: “Hamamatsu strip”: 12 strip in each of 2 90 0 detectors (blue2) Test Detector2:“Hamamatsu single”: 2 pads in each of 2 90 0 detector (yellow2) Ultra thin Carbon ribbon Target (5  g/cm 2 )1 3 4 5 6 2 Si strip detectors (TOF, E C ) 18cm

4 Overall Performance  Great efforts for polarimeter upgrade led by A.Zelenski finished on time by Run9: two independent polarimeters in each ring Very important precise cross check for pC measurements (comparison to HJet is much less precise) ~ Simultaneous measurements of polarization profile in both trans. directions Twice more targets – enough for the half a year long Spin Run New detectors tested (see talk by B.Morozov)  No major issues/complains from operation by MCR  Smooth performance … But encountered serious systematic effects

5 Hjet / pC-Blue vs fill (online values)  s=200 GeV HJet/pC ~ Const Within (large) fill- by-fill stat. errors (of HJet)

6 Hjet / pC-Yellow vs fill (online values)  s=200 GeV HJet/pC ~ Const Within (large) fill- by-fill stat. errors (of HJet)

7 Hjet / pC vs period (online values) Again no problems seen on the level of (still sizable) stat. errors HJet Periods defined by target change in any of polarimeters:

8 Response to Alphas 241Am: 5.486 MeV Example: Blue1 FebAprMayJunJul On the average, energy calibration (response to alphas) is stable within <2%

9 Response to Carbon M  E  tof 2 ToF vs E Up to 20% drop in Run9! ~10% drop in Run8

10 Energy and ToF correction (before Run9) Fit to kinematical curve for C (C-mass)  energy correction (in terms of “dead layer”) and t0 correction

11 “Dead Layer” Run5: 40-55  g/cm 2 Run6: 70-80  g/cm 2 Run8: 75-90  g/cm 2 Run9: 55-75  g/cm 2

12 T0 ToF offset drifts by ~3-6 ns! 1 ns change is equivalent to “DeadLayer”~5  g/cm 2 Is it just a fit problem (correlation between “DL” and T0)? If ~20% change in reconstructed C-mass corresponded to shift in energy scale it would mean ~20% change in asymmetry, which is not confirmed by the comparison with Hjet  T0 as measured by the system does drift! Need to monitor T0 Simple suggestion (by Gregor Atoyan and Boris Morozov): install photon detector – installed in Run9 but has not been well tested

13 Rate “problems”  s=200 GeV In “banana” cut: Run9-250 GeV: up to 150 kHz/strip Run9-100 GeV: up to 100 kHz/strip Run8-100 GeV: up to 50 kHz/strip Run6-100 GeV: up to 30 kHz/strip Effectively rates are twice higher (in the ToF-Energy window at the entrance of WFD)

14 pC Monitoring with pulser Generator pulses Carbon Ekin ToF Blue1

15 pC Monitoring with pulser Low rate example: 10429.013 20 kHz/strip High rate example: 10346.007 100 kHz/strip Pulse ToF vs time Event rate vs time Pulse rate vs time Pulse amplitude vs time

16 pC Monitoring with pulser Run 10450.116 110 kHz/strip High RateNo Rate Pulser Amplitude distribution

17 Rate effects: Mass vs Rate Rate Mass Different correlation patterns  not only rate problems (but also T0 drift etc.)

18 Rate effects: asymmetry vs bunch High rate case Low rate case Detector asymmetry is a function of bunch #: Detector (system) performance may vary vs bunch (after abort gap) and vs detector

19 Rate effects: Mass vs bunch 4% High rate case Low rate case Det 4 Det 3 Det 6 Det 1 Bunch dependence of mass  Bunch dependence of system performance (energy, tof etc.)

20 Pol1 vs Pol2  10% variation in the Pol1/Pol2 ratio vs fill (  20% variation at  s=500 GeV) No obvious correlation with “obvious” observables, such as rate, C-mass  s=200 GeV

21 Systematic effects in pC SourceEffectMonitoring Si radiation damageDead Layer increase?Change in Energy measurements  lower reconstructed C-mass “After rest” (~ a few days) Dead Layer decrease?Change in Energy measurements  higher reconstructed C-mass ??T0 driftFrom fit of E vsToF Rate effectDead Time Shift in energy measurements Event overlap Rate, dead time and shift in energy measurements (from gen. pulses), reconstructed C- mass TargetEnergy loss in targetComparison of 90 degree and 45 degree detectors? ??Pol1/Pol2 inconsistency???

22 Summary Upgraded pC polarimeter – many new opportunities New detectors tested (see talk by B.Morozov) Crucial cross check from the comparison of Pol1 vs Pol2 Smooth performance and operation by MCR Sizable systematic effects observed Rate effects “Still unknown” effects Data analysis ongoing Expect <10% (<20%) uncertainty in pol. measurements for 100 GeV (250 GeV) beams in Run9 Considering substantial system modification Better (thinner and uniform) target production (see talk by A.Zelenski) More robust detectors, smaller acceptance (see talk by B.Morozov) Faster preamps Replace WFD with simple ADC/TDC scheme?

23 Backups

24 Rate Run9-250GeV (per 48 strip) Run6 (per 72 strip) Run8 (per 72 strip) Run9-100GeV (per 48 strip)

25 C-mass Run9-250GeV Run9-100GeV Run8

26 Hjet vs pC-Blue, 250 GeV

27 Hjet vs pC-Yellow, 250 GeV

28 Hjet vs pC, 250 GeV

29 Pol1 vs Pol2: 250 GeV

Download ppt "RHIC pC Polarimeters in Run9: Performance and Issues A.Bazilevsky for the RHIC CNI Group Polarimetry Worshop BNL, July 31, 2009."

Similar presentations

E.C. Aschenauer 2013/03/132 polarisation for Blue and Yellow t o -calibration underway minimal impact on polarization, makes A N more stable  should.

E.C. Aschenauer 2013/03/132 polarisation for Blue and Yellow t o -calibration underway minimal impact on polarization, makes A N more stable  should.
PHENIX local RUN9 RHIC meeting Manabu Togawa for the PHENIX 1.

PHENIX local RUN9 RHIC meeting Manabu Togawa for the PHENIX 1.
1 Electron Beam Polarimetry for EIC/eRHIC W. Lorenzon (Michigan) Introduction Polarimetry at HERA Lessons learned from HERA Polarimetry at EIC.

1 Electron Beam Polarimetry for EIC/eRHIC W. Lorenzon (Michigan) Introduction Polarimetry at HERA Lessons learned from HERA Polarimetry at EIC.
E.C. Aschenauer Phil Pile Meeting 2012/03/202 polarisation at injection Blue and Yellow Caveat: only first round of cleaning up noise in polarimeters.

E.C. Aschenauer Phil Pile Meeting 2012/03/202 polarisation at injection Blue and Yellow Caveat: only first round of cleaning up noise in polarimeters.
AGS pp Status Feb. 6, 2015 RSC Meeting Haixin Huang.

AGS pp Status Feb. 6, 2015 RSC Meeting Haixin Huang.
RHIC/AGS Polarimeter Study May 1, 2009 H. Huang, A. Zelesnki, B. Morozov.

RHIC/AGS Polarimeter Study May 1, 2009 H. Huang, A. Zelesnki, B. Morozov.
Comments to the AGS pC polarimeter data processing t 0 based calibration Observations of Boris Morozov’s results Dead layer corrections. A novel method.

Comments to the AGS pC polarimeter data processing t 0 based calibration Observations of Boris Morozov’s results Dead layer corrections. A novel method.
PC polarimeter at RHIC. Status and performance. S. Bravar, G. Bunce +, R. Gill, H. Huang, Y. Makdisi, A. Nass, A. Zelensky: Brookhaven National Laboratory,

PC polarimeter at RHIC. Status and performance. S. Bravar, G. Bunce +, R. Gill, H. Huang, Y. Makdisi, A. Nass, A. Zelensky: Brookhaven National Laboratory,
Yousef Makdisi PSTP2011 September 12-18, 2011 Proton Polarimetry at the Relativistic Heavy Ion Collider and Future Upgrades Yousef I. Makdisi Brookhaven.

Yousef Makdisi PSTP2011 September 12-18, 2011 Proton Polarimetry at the Relativistic Heavy Ion Collider and Future Upgrades Yousef I. Makdisi Brookhaven.
The polarized hydrogen jet target measurements at RHIC Andrei Poblaguev Brookhaven National Laboratory The RHIC/AGS Polarimetry Group: I. Alekseev, E.

The polarized hydrogen jet target measurements at RHIC Andrei Poblaguev Brookhaven National Laboratory The RHIC/AGS Polarimetry Group: I. Alekseev, E.
11/18/2003Haixin Huang1 RHIC Polarimeter Status All targets and Si detectors have been installed at the end of October. The targets survived the vacuum.

11/18/2003Haixin Huang1 RHIC Polarimeter Status All targets and Si detectors have been installed at the end of October. The targets survived the vacuum.
AGS Polarized Proton Development toward Run-9 Oct. 3, 2008 Haixin Huang.

AGS Polarized Proton Development toward Run-9 Oct. 3, 2008 Haixin Huang.
Polarimetry of Proton Beams at RHIC A.Bazilevsky Summer Students Lectures June 17, 2010.

Polarimetry of Proton Beams at RHIC A.Bazilevsky Summer Students Lectures June 17, 2010.
DIS 2006 Tsukuba, April 21, 2006 Alessandro Bravar Proton Polarimetry at RHIC Alekseev, A. Bravar, G. Bunce, S. Dhawan, R. Gill, W. Haeberli, H. Huang,

DIS 2006 Tsukuba, April 21, 2006 Alessandro Bravar Proton Polarimetry at RHIC Alekseev, A. Bravar, G. Bunce, S. Dhawan, R. Gill, W. Haeberli, H. Huang,
COMPTON POLARIMETRY Collected data Cavity power Status on counting methods Systematic errors and hardware issues.

COMPTON POLARIMETRY Collected data Cavity power Status on counting methods Systematic errors and hardware issues.
7/30/99Douglas E. Fields for the E950 Collaboration 1 A CNI Polarimeter for RHIC Spin Results from IUCF CE75 & AGS E950 M. Bai, G. Bunce*, H. Huang, Y.

7/30/99Douglas E. Fields for the E950 Collaboration 1 A CNI Polarimeter for RHIC Spin Results from IUCF CE75 & AGS E950 M. Bai, G. Bunce*, H. Huang, Y.
E.C. Aschenauer RSC-Meeting, January 21st 2011 1 T h e b e s t k e p t s e c r e t n u m b e r a t R H I C / B N L / U S A f o r s u r e n o t t o b e.

E.C. Aschenauer RSC-Meeting, January 21st T h e b e s t k e p t s e c r e t n u m b e r a t R H I C / B N L / U S A f o r s u r e n o t t o b e.
Thomas Roser Snowmass 2001 June 30 - July 21, 2001 Polarized Proton Acceleration and Collisions Spin dynamics and Siberian Snakes Polarized proton acceleration.

Thomas Roser Snowmass 2001 June 30 - July 21, 2001 Polarized Proton Acceleration and Collisions Spin dynamics and Siberian Snakes Polarized proton acceleration.
PHENIX Local Polarimeter PSTP 2007 at BNL September 11, 2007 Yuji Goto (RIKEN/RBRC)

PHENIX Local Polarimeter PSTP 2007 at BNL September 11, 2007 Yuji Goto (RIKEN/RBRC)
Systematic Errors Studies in the RHIC/AGS Proton-Carbon CNI Polarimeters Andrei Poblaguev Brookhaven National Laboratory The RHIC/AGS Polarimetry Group:

Systematic Errors Studies in the RHIC/AGS Proton-Carbon CNI Polarimeters Andrei Poblaguev Brookhaven National Laboratory The RHIC/AGS Polarimetry Group:

Similar presentations

Ads by Google