Polarization Measurement of 100GeV Proton Beams at RHIC with CNI pC Polarimeter
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Polarization Measureme nt of 100GeV Proton Be ams at RHIC with CNI p C Polarimeter Itaru Nakagawa (RIKEN/RBRC) Itaru Nakagawa (RIKEN/RBRC) On behalf of CNI Polarimeter Group On behalf of CNI Polarimeter Group I.G.Alekseev I.G.Alekseev A A A.Bravar A.Bravar B B G.Bunce G.Bunce B B S.Dhawan S.Dhawan D R.Gill R.Gill B H.Huang H.Huang B B W.Haeberli W.Haeberli E E G.Igo G.Igo F O.Jinnouchi V.P.Kanavets O.Jinnouchi V.P.Kanavets A K.Kurita K.Kurita H A.Khodinov A.Khodinov J J Z.Li Z.Li B B Y.Makdisi Y.Makdisi B A.Nass A.Nass B W.Lozowski W.Lozowski I W.W.MacK W.W.MacK ay ay B H.Okada H.Okada G S.Rescia S.Rescia B T.Roser T.Roser B N. Saito N. Saito G G H.Spinka H.Spinka L L D.N.Sv D.N.Sv irida irida A D.Underwood D.Underwood L L C.Witten C.Witten F T.Wise T.Wise I J.Wood J.Wood F F A.Zelenski A.Zelenski B RBRC ITEP RBRC ITEP A BNL BNL B ANL ANL C Yale U Yale U D Wisconsin U Wisconsin U E UCLA UCLA F Kyoto U Kyoto U G G Rikkyo U Rikkyo U H H Indiana U Indiana U I StonyBrook U StonyBrook U J IUCF IUCF K K Arg Arg onne U onne U L
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Polarization Measurement of 100GeV Proton Beams at RHIC with CNI pC Polarimeter. Itaru Nakagawa (RIKEN/RBRC) On behalf of CNI Polarimeter Group - PowerPoint PPT Presentation
Transcript of Polarization Measurement of 100GeV Proton Beams at RHIC with CNI pC Polarimeter
Polarization Measurement of 100GeV Proton Beams at RHIC
with CNI pC Polarimeter
Polarization Measurement of 100GeV Proton Beams at RHIC
with CNI pC Polarimeter
Itaru Nakagawa (RIKEN/RBRC)Itaru Nakagawa (RIKEN/RBRC)On behalf of CNI Polarimeter GroupOn behalf of CNI Polarimeter GroupI.G.AlekseevI.G.AlekseevA A A.BravarA.BravarB B G.BunceG.BunceB B S.DhawanS.DhawanDD R.Gill R.GillBB H.Huang H.HuangB B W.HaeberliW.HaeberliE E G.Igo G.IgoFF O.Jinnouchi V.P.Kanavets O.Jinnouchi V.P.KanavetsAA K.Kurita K.KuritaHH A.Khodinov A.KhodinovJ J Z.Li Z.LiB B Y.Makdi Y.MakdisisiBB A.Nass A.NassBB W.Lozowski W.LozowskiII W.W.MacKay W.W.MacKayBB H.Okada H.OkadaGG S.Rescia S.ResciaBB T.Roser T.RoserBB N. N. SaitoSaitoG G H.Spinka H.SpinkaL L D.N.SviridaD.N.SviridaAA D.Underwood D.UnderwoodL L C.Witten C.WittenFF T.Wise T.WiseII J.Wood J.WoodF F A.A.ZelenskiZelenskiBB
RBRC ITEPRBRC ITEPAA BNL BNLBB ANL ANLCC Yale U Yale UDD Wisconsin U Wisconsin UEE UCLA UCLAFF Kyoto UKyoto UG G Rikkyo URikkyo UH H Indiana UIndiana UII StonyBrook U StonyBrook UJJ IUCF IUCFK K Argonne UArgonne ULL
Itaru Nakagawa (RIKEN/RBRC)Itaru Nakagawa (RIKEN/RBRC)On behalf of CNI Polarimeter GroupOn behalf of CNI Polarimeter GroupI.G.AlekseevI.G.AlekseevA A A.BravarA.BravarB B G.BunceG.BunceB B S.DhawanS.DhawanDD R.Gill R.GillBB H.Huang H.HuangB B W.HaeberliW.HaeberliE E G.Igo G.IgoFF O.Jinnouchi V.P.Kanavets O.Jinnouchi V.P.KanavetsAA K.Kurita K.KuritaHH A.Khodinov A.KhodinovJ J Z.Li Z.LiB B Y.Makdi Y.MakdisisiBB A.Nass A.NassBB W.Lozowski W.LozowskiII W.W.MacKay W.W.MacKayBB H.Okada H.OkadaGG S.Rescia S.ResciaBB T.Roser T.RoserBB N. N. SaitoSaitoG G H.Spinka H.SpinkaL L D.N.SviridaD.N.SviridaAA D.Underwood D.UnderwoodL L C.Witten C.WittenFF T.Wise T.WiseII J.Wood J.WoodF F A.A.ZelenskiZelenskiBB
RBRC ITEPRBRC ITEPAA BNL BNLBB ANL ANLCC Yale U Yale UDD Wisconsin U Wisconsin UEE UCLA UCLAFF Kyoto UKyoto UG G Rikkyo URikkyo UH H Indiana UIndiana UII StonyBrook U StonyBrook UJJ IUCF IUCFK K Argonne UArgonne ULL
Polarimetry: Impact on RHIC-SPINPolarimetry: Impact on RHIC-SPIN
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ALL =1
Pbeam2
N↑↑ − N↑↓
N↑↑ + N↑↓
⎛
⎝ ⎜ ⎜
⎞
⎠ ⎟ ⎟ ⇒ ΔG
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AN =1
Pbeam
N↑ − N↓
N↑ + N↓
⎛
⎝ ⎜ ⎜
⎞
⎠ ⎟ ⎟
Physics AsymmetriesSingle Spin Asymmetries
Double Spin Asymmetries
Polarization measurement by Elastic pp/pC
Polarized proton Recoil carbon
90º in Lab frame
Carbon target
↓↑LL NN or
↓↑RR NN or
↓↑or
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Pbeam = −εN
ANpC
εN =NL − NR
NL + NR
Pbeam Required Accuracy ~5%
Pbeam Required Accuracy ~5%
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rp p( p
r p ) /
r p C
AN at Coulomb Nuclear Interference (CNI) RegionAN at Coulomb Nuclear Interference (CNI) Region
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AN ≈ C1φ flipem *
φnon− fliphad + C2φnon− flip
em *φ flip
had
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∝ σ pChad
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∝ (μ p −1)
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∝αst ? Pomeron exchange
zero hadronic spin-flip
With hadronic spin-flip (E950)
Phys.Rev.Lett.,89,052302(2002)
pC Analyzing Power
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ANpC =
1
Pbeam
εN Requires absolute calibration
p = 21.7GeV Need to measure ANpC @ 100GeV
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ANbeam (t) = −AN
target (t)
Pbeam = −Ptarget
εbeam
ε target
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rp beam
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rp target
Elastic pp
(High energy & small t limit)
Characteristics of pC polarimeterCharacteristics of pC polarimeter
• Large Cross Section
• Solid target
• 20 sec./measurement with (sta) ~ 2%
• Immediate feedback to accelerator operation
• “Fill by Fill” & “Bunch by Bunch” measurement
• Polarization profile measurement
• ANpC ~ a few %
High Event Rate
RHIC PolarimetryRHIC Polarimetry
BRAHMS & PP2PP (p)
STAR (p)PHENIX (p)
AGS
LINAC BOOSTER
Pol. Proton Source500 A, 300 s
Spin RotatorsSolenoid Snake
Siberian Snakes
200 MeV Polarimeter
AGS pC CNI PolarimeterAC Dipole
RHIC pC Polarimeters
Absolute Polarimeter (H jet)
RHIC
Siberian Snakes
Cold Snake
Warm Snake
pC Detector SetuppC Detector SetupUltra thin Carbon ribbon Target(3.5 g/cm2)
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3344
55
66
22
Si strip detectorsSi strip detectors(TOF, E(TOF, ECC))
15cm15cm
10mm10mm
2mm pitch 12 strips2mm pitch 12 strips
pp++ implants implants~150 nm depth~150 nm depth
72 strips in total72 strips in total
Thin dead layer for low energy Thin dead layer for low energy carbon spectroscopy carbon spectroscopy
~100mV
BunchBunch
Ne
xt
Bu
nc
hN
ex
t B
un
ch
(60
bu
nc
h m
od
e)
(60
bu
nc
h m
od
e)
Shaped Si Signal
Ne
xt
Bu
nc
hN
ex
t B
un
ch
(12
0 b
un
ch
mo
de
)(1
20
bu
nc
h m
od
e)
Wave Form Digitizer (WFD)Wave Form Digitizer (WFD)420 Msamples/sec
- Pulse Height - Bunch ID- TOF - Integral (Q)- TMAX - revolution #
Select carbons at on-board LUTSelect carbons at on-board LUT Scaler dataScaler data Asymmetry calculationAsymmetry calculation Online results (to experiments)Online results (to experiments)
Event by event dataEvent by event data Stored in on-board memoryStored in on-board memory Used for offline detailed studyUsed for offline detailed study
offline
online
Redundancy
Systematic/Consistency Check
Event SelectionEvent Selection
+3σ
-3σ
12C
α
Run4
Run5
Run05 Online ResultsRun05 Online Results
PHENIXPhysics Store
Fill Number Fill Number
Pol
ariz
atio
n [%
]
Pol
ariz
atio
n [%
]P
olar
izat
ion
[%]
Run5 Polarization Profile Run5 Polarization Profile
2mm
2mm
Pol
ariz
atio
nC
ount
Rat
e[H
z]
Cou
nt R
ate[
Hz]
pC extended t-range AN @ 100GeVpC extended t-range AN @ 100GeV
No Hadronic Spin flip
Best Fit with Hadronic Spin-fliphep-ph/0305085
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ANpC =
1
Pbeam
εN
From Run4 pp
ANpC@100GeV will soon be finalized
> 0.1(GeV/c)2
Run5
Data from Run4
Preliminary
SummarySummary
• RHIC Beam Polarization was measured by taking
asymmetry of pC elastic scattering.
• Absolute calibration was done using Pbeam determin
ed by elastic pp scattering data(Run4).
• ANpC was measured for extended t range (Up to t>
0.1 (GeV/c)2 )to explore t-evolution of hadronic spi
n-flip amplitude.
• RHIC Beam Polarization was measured by taking
asymmetry of pC elastic scattering.
• Absolute calibration was done using Pbeam determin
ed by elastic pp scattering data(Run4).
• ANpC was measured for extended t range (Up to t>
0.1 (GeV/c)2 )to explore t-evolution of hadronic spi
n-flip amplitude.
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rp
r p
