Summary Session 7: Acceleration, Storage, and Polarimetry of Polarized Protons 1.) Acceleration,...

Summary Session 7: Summary Session 7: Acceleration, Storage, and Polarimetry Acceleration, Storage, and Polarimetry

of Polarized Protonsof Polarized Protons

1.) Acceleration, Storage, and Spinflipping at existing Facilities:AGS, RHIC, COSY, JINR Nuclotron, Bates South Hall Ring

2.) Polarimetry: CNI Polarimeter, Deuteron Polarization at High Energy, Stern-Gerlach polarimeter, Compton Polarimeter,

Beam-Beam Counter Polarimeter

3.) Spin Motion in Circular Machines: EDM, g-2

4.) Plans for Polarized Beams at Future Machines:eRHIC, HESR, J-Park

18 Talks

A. Lehrach, FZ JülichA. Lehrach, FZ Jülich

16th International Spin Physics Symposium, October 10-16, 2004, Trieste (Italy)

Polarized Protons at the Polarized Protons at the AGS AGS

(Commissioning FY05)

Acceleration of Polarized Protons in the AGS with a

Helical Partial SnakeH. Huang et al.

ACCELERATION OF POLARIZED BEAMS USING MULTIPLE STRONG PARTIAL SIBERIAN SNAKES

T. Roser L.A. Ahrens, M. Bai, E. D. Courant, J.W. Glenn, R. C. Gupta, H. Huang, A.U. Luccio, W.W. MacKay, N. Tsoupas, E. Willen

AGS Helical Warm Snake

8% and 5.9% partial snake

1.) Less coupling Stronger snake less concern about the coupling resonances.

2.) Less effect from horizontal dimension

Less parameters to worry about (horizontal emittance, horizontal tunes).

20 22 24 26 28 30 32 34 36 38 40 42 44 46 48

Asy

mm

etry

0.000

0.005

0.010

0.015

G20 22 24 26 28 30 32 34 36 38 40 42 44 46 48

Rat

e

0.0e+0

5.0e+5

1.0e+6

1.5e+6

Ramp Measurement

36 +

48 -

24 +

36 -

Polarization loss:~10% at 0 + ~6% at 24 + ~12% at 48- ~10% at 36 + (~18% last year)

2003 ramp measurement: 28% pol.

2004 ramp measurement: 43% pol.

Break down the gain factor: ~1.25(40%->50%)1.09 at 0 + 1.09 at 36 + 1.08 higher source pol.

50% polarization at AGS extraction

with AC Dipole & warm helical partial snake

Strong Partial Siberian Snake for AGS

A strong partial Siberian snake generates large spin tune gap for G = n. With strong enough snake, gap is large enough to cover both imperfection and intrinsic spin resonances.

Note: With a strong snake, the stable spin detection will deviate from vertical direction (18 degree for 20% snake).

Gsp cos2/coscos1 1

Intrinsic resonance

Imperfection resonance

30 % AGS super-conducting helical snake

Completed helical dipole coil

Correction solenoid and dipoles

Measured twist angle2 deg/cm in the middle~ 4 deg/cm at ends

AGS strong snake – orbit and optics matching

Cold snake

4 quadrupoles for optics matching

Vertical component of stable spin

Fractional part ofspin tune

Injection First intrinsic resonance (0+)G

Two partial snakes in the AGSD

evia

tion

fro

m in

tege

r

If vertical tune and super-periodicity

have common factor that is odd

multiple partial snakes can be used

to give larger effective strength

Polarized Protons atPolarized Protons at RHICRHIC

RHIC Polarized Proton New Working Point Commissioning

M. BaiL. Ahrens, K. Brown, A. Drees, C. J. Gardner, J. W. Glenn, W. Fischer, H. Huang, Y. Luo, F. Pilat, W. W. MacKay, G. Marr, C. Montag, V. Pitisyn, T. Roser, T. Satogata, R. Tomas,

S. Tepikian, N. Tsoupas, J. Van Zeijts

Status of proton polarization in RHIC and AGS (Invited)

W.W. MacKay et al.

Snake depolaring resonance observed in RHICV.Ptitsyn

M. Bai, H. Huang, W. W. MacKay, T. Roser, S. Tepikian

RHIC Layout

BRAHMS & PP2PP (p)

STAR (p)

PHENIX (p)

AGS

LINACBOOSTER

Pol. H- Source

Spin Rotators(longitudinal polarization)

Solenoid Partial Siberian Snake

Siberian Snakes

200 MeV Polarimeter AGS Internal Polarimeter

Rf Dipole

RHIC pC PolarimetersAbsolute Polarimeter (H jet)

AGS pC PolarimetersStrong AGS Snake

Helical Partial Siberian Snake

PHOBOS

Spin Rotators(longitudinal polarization)

Spin flipper

Siberian Snakes

Installed and commissioned during FY04 runPlan to be commissioned during FY05 runPlan to be installed and commissioned during FY05 run

RHIC intrinsic spin depolarization resonance spectrum

Intr

insi

c sp

in r

eso

nance

Qx=

28.7

3,

Qy=

29.7

2,

em

it=

10

achieved

Experiment results

Snake resonance

Both working points around 0.735 and 0.685 demonstrated similar effect on the beam lifetime in the beam-beam presence

working point around 0.685 yielded better beam polarization transmissmion effciency. 0.685 ~ 88% 0.735 ~ 75%

Snake resonances

Two types: m odd. Caused by an intrinsic

resonance alone. m even Caused by an

interference between imperfection and intrinsic resonances.

First discovered and studied by S.Y.Lee and S.Tepikian

2 1 +

2sk

Qm m

leads to resonance splitting

Resonances of interest.

Before Run4: [0.2,0.25] bet.tune working area -> {Q} = 1/4 ; 3/14

Run 4: [0.68,0.75] bet.tune working area -> {Q} = 3/4 ; 7/10

Run 4. Betatron tune scan

0

10

20

30

40

50

60

0.66 0.68 0.7 0.72 0.74 0.76

Qy in yellow at injection

po

l in

ye

llow

at

inje

cti

on

0

4

8

12

16

20

24

28

32

36

0.724 0.728 0.732 0.736 0.74 0.744 0.748

measured yellow vertical tune

polar

izatio

n at in

jectio

n

Snake inner current at 326A Snake inner current at 321A

Yellow vertical tune scans were done at the injection energy at different snake current settings. They showed clear depolarization effect of ¾ resonance, which also depended on the snake current.

No clear effect from 7/10 resonance was seen (both at the injection and store energies).

Snake current scan

0

5

10

15

20

25

30

35

40

45

50

300 305 310 315 320 325 330 335

Yellow snake inner current, A

Po

lari

zati

on

, %

-0.02

-0.018

-0.016

-0.014

-0.012

-0.01

-0.008

-0.006

-0.004

-0.002

0

D/

Polarization Snake resonance shift

Done at the injection energy. Changing inner snake current effectively shifts the spin tune (and the position of the snake resonance).

{Qy}=0.74 323 A optimum 321 A optimum

0

5

10

15

20

25

30

35

40

45

50

300 305 310 315 320 325 330 335

Blue snake inner current, A

Po

lari

zati

on

, %

-0.02

-0.018

-0.016

-0.014

-0.012

-0.01

-0.008

-0.006

-0.004

-0.002

0

D/

Polarization Snake resonance shift

Conclusion

Two new working points were explored during the FY04 RHIC pp run. Both demonstrated better luminosity performance. Working point around 0.685 yielded higher polarization transmission efficiency as well as better polarization lifetime.

bunch intensity

[1011]

# of bunch

£peak

[1030]cm-2s-1

£store average

[1030]cm-2s-1

£per week

[pb-1]polarization

at store

FY04Polarized

proton0.70 56 5.4 4.0 1.0 40-45%

FY04Unpolarized

proton1.70 28 10.0 -- -- --

Spin Flipping Vector and Tensor Polarized Deuterons


Higher-Order Spin Resonances

Third order spin resonances are strong !

Spin Flipping Polarized Protons

Spin Flipping Polarized Protons

• Frequency sweep parameter:

Δf/2 = 6 KHz

Δt = 0.1sec

• Fit to Pf = Pi (-η)n gives η= 99.92±0.04%.

POLARIZED DEUTERONS AT THE JINRACCELERATOR NUCLOTRON

Yu.K.Pilipenko, S.V.Afanasiev, L.S.Azhgirey, A.Yu.Isupov, V.P.Ershov, V.V.Fimushkin, L.V.Kutizova,

V.F.Peresedov, V.P.Vadeev, V.N.Zhmyrov, L.S.Zolin

Joint Institute for Nuclear Research

POLARIZATION at the NUCLOTRON

20 years of intensive study of polarization phenomena in high energy spin physics with the Dubna 10 GeV synchrophasotron

In fall of 2002 last polarized beam run, the old historical machine was shutdown

Test run at the new SC accelerator nuclotron has been done

to get polarized beam and continue spin physics program

D- CHARGE EXCHANGE IONIZER• To reach the accelerated polarized beam intensities up to 0.7-1*1010 d/pulse

multi-turn charge exchange injection (20-30 turns) by stripping injection of D- ions• Polarized D- beam is required existing D+ plasma charge exchange ionizer has been

modified into D- ionizer using an external converter-emitter. • At output of the H+ plasma generator, a molybdenum converter is placed to produce H-

ions. Cesiated molybdenum surfaces of the converter are exposed to an intense flux of superheated hydrogen atoms, positive ions and effectively generate H- ions.

• H- ions, generated inside the converter, space charge compensated by residual H+ ions, are fill up a charge exchange space of the HV pipe.

• The reaction D0+H- = D- +H0 takes place.

TEST RUN at the NUCLOTRON

Simulation shows that depolarizating resonances are absent under polarized deuteron acceleration almost at all energy range of the machine. A special test run has been done at the nuclotron using the existing D+ source POLARIS with Penning ionizer to check the polarization of low and high energy beams during acceleration.

The results of measurements are: Pz(1-4) Pz(3-6)

1. Beam polarization measured -0.56+/-0.07 0.62+/-0.07

behind the linac

2. Internal target measurements

at 3.5 GeV/c -0.58+/-0.04 0.59+/-0.04

at 5.0 GeV/c -0.56+/-0.03 0.60+/-0.03

3. Polarization of the extracted beam

at 3.5 GeV/c -0.54+/-0.02 0.56+/-0.02

at 5.0 GeV/c -0.66+/-0.02 0.60+/-0.02

The vector polarization of the deuteron beam during acceleration is saved and confirmed by all polarimeters.

As expected due to one turn injection mode an intensity of the polarized deuteron beam is observed as 1.3108d/pulse. The charge exchenge miltyturn injection is required.

The Bates South Hall Ring:

A Unique Instrument for Studying Polarization

D. Cheever, K.Dow, M. Farkhondeh, W. Franklin, D. Hasell,E. Ihloff, S. Krause, L.Longcoy, C. Tschalaer, E. Tsentalovich,

J. van der Laan, F. Wang, A. Zolfaghari, T. Zwart

The MIT-Bates Compton Polarimeterfor the South Hall Ring

W.A. Franklin for the BLAST Collaboration

• Standard: Linac and recirculator provide intense polarized electron beams up to 1 GeV at 600 Hz, low duty cycle

• Pulse Stretcher (OOPS): Limited turns in South Hall Ring before gradual extraction to external target

• Storage (BLAST): Gradual stacking of electron pulses in South Hall Ring for long-lived CW beam

MIT-Bates Linear Accelerator Center

Three distinct modes of operation driven by needsof experiments

Polarization in the South Hall Ring

e

Full Siberian Snake (Budker) restores longitudinal beam polarization at target

Compton polarimeter

Spin Flipper

Monitoring beam polarization in the ring.

• Spin-flipping RF dipole allows dynamic spin reversal of stored beams (Michigan)

• Inject beam for peak longitudinal polarization at internal target (Wien filter in polarized source)

Siberian Snake Calibration

• Nominal current-based calibration corrected to Siberian Snake by 0.4%.

• Siberian Snake strength determined by electron energy, solenoidal field

• Spin flip resonant frequency provides sensitive measurement of spin tune as function of Siberian Snake current

Compton Polarimetry Below 1 GeV

• Bates seeks precise polarization measurement for each ring fill (15 minutes) for experiments with BLAST.

Bates

JLab

HERA532 nm laser light

• Compton polarimetry is well established at high energy accelerators (Apol~0.5)

• Different challenges exist in applying at energies below 1 GeV. > Analyzing power falling with energy (Apol < 0.05)> Interaction mechanism varies with gamma ray energy> Broader angular distribution for photons> Background from low energy photons> Beam lifetime less than 1 hour

Electron Energy (MeV)

Compton Analyzing Power

Ap

ol

Fill-by-Fill Polarization Results

• Polarization reversed in electron source on fill-by-fill basis• Polarization monitored continuously• Typical precision of 4-5% for ~15 minute fill• Gaussian profile to results

Time (hours)

Pola

riza

tion

South Hall Ring Polarization

• Compton polarimeter data from Dec. 2003 – Sept.2004• Mean polarization of 66.3% during BLAST experiments

Polarization and Tune Spreading

• Initially, large losses of P for high I, restored by changing ring lattice.• Effect linked to betatron tune shifts and spreading from trapped ions• Practical solution: operate away from expected spin-orbit resonances, empirical hunt for max polarization• Limited study of polarization as function of current, storage time, and tune• Relevant issue for high luminosity devices (Electron-Ion Collider)

y

PL

BLAST Experiment

• South Hall Ring: Intense (175 mA) stored CW polarized electron beams in at 850 MeV

• BLAST Atomic Beam Source: (E. Tsentalovich, 10/15 Session 8)

• BLAST: Symmetric detector with wide momentum transfer bite

• Beam-target polarization product from BLAST asymmetry.• Need rapid nondestructive measurement of beam polarization. • Laser backscattering can provide.

Measure asymmetries using polarized beams and targets




2.) Polarimetry: Compton Polarimeter, CNI Polarimeter, Deuteron Polarization at High Energy, Stern-Gerlach polarimeter, Beam-

Beam Counter Polarimeter





Spin Dependence in Elastic ScatteringSpin Dependence in Elastic Scattering

in the CNI Region:in the CNI Region: p ppp pppp & & ppC C ppCC

A. Bravar, I. Alekseev, G. Bunce, S. Dhawan, R. Gill, H. Huang, W. Haeberli, G. Igo,

O. Jinnouchi, A. Khodinov,K. Kurita, Z. Li, Y. Makdisi, A. Nass, H. Okada, S. Rescia, N. Saito, H. Spinka, E. Stephenson, D. Svirida, D. Underwood,C. Whitten, T. Wise, J.

Wood, A. Zelenski

p-Carbon CNI Polarimeters at BNL – the Fastest Physics Setup in the World.

D. Svirida I.Alekseev A.Bravar G.Bunce S.Dhawan R.Gill H.Huang W.Haeberli G.Igo

O.Jinnouchi V.Kanavets K.Kurita A.Khodinov Z.Li Y.Makdisi A.Nass W.Lozowski W.W.MacKay H.Okada S.Rescia T.Roser N.Saito H.Spinka E.Stephenson D.Underwood C.Witten T.Wise

J.Wood A.Zelenski

RHIC RHIC pppp accelerator complex accelerator complex

BRAHMS & PP2PP

STARPHENIX

AGS

LINACBOOSTER

Pol. Proton Source

Spin Rotators

20% Snake

Siberian Snakes

200 MeV polarimeter

AGS quasi-elastic polarimeter

Rf Dipoles

RHIC pC “CNI” polarimeters

PHOBOS

RHIC

absolute pHpolarimeter

SiberianSnakes

AGS pC “CNI” polarimeter

5% Snake

The Very Low The Very Low tt Region Regionaround t ~ 103 (GeV/c)2 Ahadronic ACoulomb

INTERFERENCE

CNI = Coulomb – Nuclear Interferencescattering amplitudes modified to include also electromagnetic contribution

hadronic interaction described in terms of Pomeron (Reggeon) exchange

electromagnetic single photon exchange

= |Ahadronic + ACoulomb|2

unpolarized clearly visible in the cross section d/dt charge

polarized “left – right” asymmetry AN magnetic moment

+P

iemi

hadi

hadi e

the left – right scattering asymmetry AN arises from the interference of

the spin non-flip amplitude with the spin flip amplitude (Schwinger)

in absence of hadronic spin – flip contributions

AN is exactly calculable (Kopeliovich & Lapidus):

hadronic spin- flip modifies the QED“predictions”

interpreted in terms of Pomeron spin – flip and parametrized as

AANN & Coulomb Nuclear Interference & Coulomb Nuclear Interference

hadflipnon

hadflip

hadflipnon

emflipN CCA *

2*

1

1)p pp

had

Zt

yy

y

m

ZA

pAtot

pAtotp

N 81

1

82

2/3

2

25 2

1

2

1

2

1II ppp

AN (t)

had

p

had

mt

s 15 )(

Some ASome AN N measurements in the CNI measurements in the CNI regionregion

pp Analyzing Power

no hadronicspin-flip

-t

AN

(%)

E704@FNALp = 200 GeV/cPRD48(93)3026

E950@BNLp = 21.7 GeV/cPRL89(02)052302

with hadonicspin-flip


pC Analyzing Power

r5pC Fs

had / Im F0had

Re r5 = 0.088 0.058

Im r5 = 0.161 0.226

highly anti-correlated

The Atomic H Beam The Atomic H Beam SourceSource

separationmagnets(sextupoles)

H2 dissociator

Breit-Rabipolarimeter

focusingmagnets(sextupoles)

RF transitions

holding field magnet

recoil detectorsrecord beam intensity100% eff. RF transitionsfocusing high intensityB-R polarimeter

OR

Pz+ OR Pz

-

H = p+ + e-

the JET ran with an average intensity of 11017 atoms / sec

the JET thickness of 1 1012 atoms/cm2 record intensity

target polarization cycle+/0/- ~ 500 / 50 / 500 sec

polarization to be scaled

down due to a ~3% H2

background:

Ptarget ~ 0.924 ± 0.018

(current understanding)

no depolarization from beamwake fields observed !

JET target polarization & performanceJET target polarization & performance

0.9

4

0.9

6

0.9

8

pol

.

minus polarization

plus polarization

2.5 h time

Recoil Si spectrometerRecoil Si spectrometer

6 Si detectors coveringthe blue beam =>MEASURE energy (res. < 50 keV) time of flight (res. < 2 ns) scattering angle (res. ~ 5 mrad)of recoil protons frompp pp elastic scattering

HAVE “design”azimuthal coverage

one Si layer only smaller energy range reduced bkg rejection power

B

ANbeam (t ) AN

target (t )

for elastic scattering only!

Pbeam = Ptarget . Nbeam / N

target

this expt.E704@FNAL

AANN for for ppp p pp pp @ 100 GeV @ 100 GeV

data in this t regionbeing analyzed

prel

imin

ary

data (from this expt. only) fitted with CNI prediction

[TOT = 38.5 mbarn,

= 0, = 0]

fitted with:

N f CNI

N – “normalization factor”N = 0.98 0.03

2 ~ 5 / 7 d.o.f.

the errors shown arestatistical only(see previous slide)

no need of a hadronic spin – flip contribution to describe these datahowever, sensitivity on 5

had in this t range low


Setup for Setup for ppC scattering – C scattering – the RHIC the RHIC polarimeterspolarimeters

recoil carbon ions detected with Silicon strip detectors

2 72 channels read out with WFD (increased acceptance by 2)

very large statistics per measurement (~ 20 106 events) allows detailed analysis– bunch by bunch analysis– channel by channel (each channel is an “independent polarimeter”)– 45o detectors: sensitive to vertical and radial components of Pbeam unphysical asymmetries

Ultra thin Carbon ribbon Target

(3.5g/cm2 ,10m)

beamdirection

1

34

5

6

RHIC 2 rings

2

Si strip detectors(ToF, EC)

30cm

inside RHIC ring @IP12

AANN for for ppCC p pC @ 100 GeVC @ 100 GeV


with hadronicspin-flip

“forbidden” asymmetries

systematicuncertainty

best fit withhadronic spin-flip

Kopeliovich –Truemann modelPRD64 (01) 034004hep-ph/0305085

prel

imin

arystatistical errors only

A RIKEN BNL Research Center Workshop A RIKEN BNL Research Center Workshop A RIKEN BNL Research Center Workshop

RHIC… Polarization History in pp Run’04

D.Svirida (ITEP/BNL)

Po

lari

zati

on

Po

lari

zati

on

Po

lari

zati

on

Po

lari

zati

on

Days from April 1Days from April 1stst

Days from April 1Days from April 1stst

Change in Si dead layer parametersChange in Si dead layer parameters

Data PointsData Points

Black : 24GeVBlack : 24GeVColor : 100GeVColor : 100GeV

little loss or none at the ramplittle loss or none at the ramp

Jet data takingJet data taking dedicated dedicated

Non-dedicatedNon-dedicated

switch to switch to horizontal targethorizontal target

ONLINE

Results

from O

. Jinnouch

i

A RIKEN BNL Research Center Workshop A RIKEN BNL Research Center Workshop A RIKEN BNL Research Center Workshop

AGS… Asymmetry during the Ramp

D.Svirida (ITEP/BNL)

Asymmetry flips sign at every G = n

~1 ms bin width

G

Raw

asy

mm

etry

= A

N

Pbe

am

25 30 35 40 45

0.015

0.01

-0.015

-0.005

-0.01

0.005

0

Ebeam12 14 16 18 20 22 24

Results from J. Wood

τ = 0

τ = 0.214-0.054i

Design and Test of a Prototype Cavity for a Stern-Gerlach Polarimeter

P. Cameron1, M. Conte4, N. D’Imperio1, W. Franklin6, D.A.Goldberg3, A. Luccio1, M. Palazzi4,

M. Pusterla5, R. Rossmanith2, W. MacKay1, T. Zwart6

1Brookhaven National Laboratory, Upton, NY 11973, USA2Forschungszentrum Karlsruhe GmbH, D-76021 Karlsruhe, Germany

3Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA4Universita and Sezione INFN di Genova, 16146 Genova, Italy5Universita and Sezione INFN di Padova, 35131 Padova, Italy

6MIT-Bates Laboratory, Boston MA 01949 USA

Conte et al - Transverse

• Reference – LANL preprint 0003069• Transverse magnetic moment is invariant• BUT - interaction of moment with appropriate TE cavity mode

goes as 2

• analogous to inverse Compton scattering, FELs,???…

• Second proposal for a longitudinal spin splitter – kick ~ 2

• Second proposal for polarimeter at MIT-Bates - signal ~ 4

• Cheap, fast, accurate, non-destructive polarimeter• Possibility of calibration from first principles (straightforward

EM calculations, comparison with signal from charge) • We learn a lesson - the Italians (Waldo MacKay is an honorary

Genoese) are both smart and tenacious

Prototype Cavity

• Refine frequency calculations to include beampipe perturbation• Determine probe length for optimal coupling• Determine optimal coupling for TM mode dampers• Investigate need for tuners TE011 on-axis Fields

Bates S/N

Bates

rad

bkg

signal -60dBm

dBm

dBm

• TE011 mode• Signal strength is good

• Schottky ~ -150dBm• Charge background requires alignment at the level of a few rad• First choice is motion control, cheapest is beam steering

Suppression of Coherent Betatron Oscillations in muon (g-2)

experiment

Yu.M.ShatunovI.A.Koop, A.V.Otboev, E.A.Perevedentsev,

P.Yu.Shatunov

Budker Institute of Nuclear Physics, Novosibirsk, Russia

Injection: p → π+ → μ+ + ν

E-quads

Scheme and parametersScheme and parameters

R = 7.112 mB = 1.45 TΔB/B ≤ 10-6

Nμ (t = 0) ~ 5000 τ = γτ0 ≈ 6.5·10-5 sec

Eμ = 3.096 GeV(“magic” energy )

electrostatic focusing!

Kicker100 kV

detectors

e+

μ+

ν

2 22 2 2 22 2 (1 ) 2(1 ) 2 y y y yx x x x

x y

y y y yx x x xA

g-2

gradient (Gauss/cm3)

0.000.150.400.85

CBO “damping” with nonlinear fieldsnonlinear fields

turns

g-2

0 10 200

0.5

11

0

I t( )

200 t

Octupole coiland parameters of generator

+

+

-

-

6 cm

Coil length 16×2 m Current 2.5 kA Capacitor 1 μFVoltage 1.3 kVEnergy 1.0 JHalf period 10 μsec

μsecinjection

2.5 kA

1.25

I(t)

PoPolarized Beams in the High-Energy larized Beams in the High-Energy Storage Ring of the Future GSI ProjectStorage Ring of the Future GSI Project

HESR Polarimeter

AP Polarimeter

Snake

LE Polarimeter

Snake

HESR: 1.5-15GeV/c

AP: 0.24 – 1.5GeV/c

30 MeV Linac

A. Lehrach, R. Maier, D.Prasuhn, Jülich; A.U. Luccio, BrookhavenA. Lehrach, R. Maier, D.Prasuhn, Jülich; A.U. Luccio, BrookhavenI. Koop,I. Koop, A. Otboyev, Yu.M. Shatunov, A. Otboyev, Yu.M. Shatunov, NovosibirskNovosibirsk

Siberian Snake for HESRSiberian Snake for HESR(Solution I)(Solution I)

Helical dipoles

Solenoid

Partial Snake for HESR Partial Snake for HESR (Solution II)(Solution II)

In addition to the 15 Tm Cooler solenoid add four more solenoids with the same total integral field in the same straight.

From injection up to about 7.5 GeV/c both solenoid will provide a full spin flip. At higher momenta they will work as partial snake with about 50% snake at top energy .75 < Qfrac < .25

To compensate coupling from solenoids eight quads are needed, rotated by:0.14956 rad, 0.11217 rad, 0.07478 rad, 0.07478 rad at max.

Quads have to be rotated depending on strength of solenoid fields and beam energy. No orbit excursion No coupling outside the insertion

Wy

SPIN2004@TRIESTE Oct. 10-16, 2004 Hikaru Sato, KEK-PS & J-PARC

Polarized Proton Acceleration

at the J-PARC Accelerator Complex

C. Ohmori, T. Toyama, Y. Mori, KEK-PS & J-PARCK. Hatanaka, RCNPM. Okamura, RIKEN

SPIN2004, Trieste Italy, October 10-16, 2004

Hikaru SATO, KEK-PS & J-PARC

mailto:SPIN2004@TRIESTE


Configuration of the accelerator complex



Summary of Calculation Result

by K. Hatanaka

● 3 GeV ring(a) intrinsic resonances

Emittance should be large.(200 mm ・ mrad at 0.4

GeV)

(b) imperfection resonancesClosed orbit distortion should be small.(0.1 mm)

(b) imperfection resonancesClosed orbit distortion shoul be

small.Partial snake.

● 50 GeV ring(a) intrinsic resonances

Tune jump is needed.Siberian Snake does not work.

Strong solenoid field (type 1 snake).Large orbit excursion

(Steffen Sake, Helical Snake).



Issues

Polarized ion sourceLow intensity beam operationPolarimeterInjector : RCS or LINAC or FFAG Cure of depolarizing resonance Fast tune jump Coherent betatron motion excitation COD harmonic correction or excitation Partial Siberian snake Full snake ?? Spin rotatorSpin flipperSpin tracking simulation


Summary Session 7: Acceleration, Storage, and Polarimetry of Polarized Protons 1.) Acceleration,...

Documents

Transcript of Summary Session 7: Acceleration, Storage, and Polarimetry of Polarized Protons 1.) Acceleration,...