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Why are We Discussing polarised H e -3 Beams Now?

Why are We Discussing polarised H e -3 Beams Now?. I s all in place to start work on polarized He 3 ??. Need some years to implement a polarized He 3 beam Decadal planning process in full swing. Pol. Source. Polarimetry. Pol. RHIC. Physics. eRHIC. Polarized Beams in RHIC.

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Why are We Discussing polarised H e -3 Beams Now?

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  1. Why are We Discussingpolarised He-3 Beams Now? E.C. Aschenauer He-3 Workshop, BNL, September 2011

  2. Is all in place to start work on polarized He3 ?? • Need some years to implement a polarized He3 beam • Decadal planning process in full swing Pol. Source Polarimetry Pol. RHIC Physics eRHIC E.C. Aschenauer He-3 Workshop, BNL, September 2011

  3. Polarized Beams in RHIC E.C. Aschenauer He-3 Workshop, BNL, September 2011

  4. The BNL Accelerator Complex Jet/C-Polarimeters 12:00 o’clock eLenses 10:00 o’clock ANDY 2:00 o’clock RHIC PHENIX 8:00 o’clock RF 4:00 o’clock STAR 6:00 o’clock LINAC NSRL EBIS Booster ERL Test Facility AGS 860 m transfer line Tandems E.C. Aschenauer He-3 Workshop, BNL, September 2011

  5. RHIC polarized protons – luminosity and polarization • <P> increased from 37% to • 46% at 250 GeV in Run-11still significant effort needed to • reach goal of 70% • also for 100GeV Beams • Building blocks for pp design • luminosity at 250 GeV • demonstrated in Run-9 and • Run-11need to be put togetherplans to go beyond • Expect no significant • increase in luminosityat • 100 GeVbefore electron • lenses E.C. Aschenauer He-3 Workshop, BNL, September 2011

  6. Luminosity and Polarization Goals E.C. Aschenauer He-3 Workshop, BNL, September 2011

  7. Run 11 Polarization Performance • AGS horizontal tune jump system operational: P +8% with high intensity • Acceleration near Qv = ⅔ in RHIC, measured orbit rms ~20 mm: P +25% • Polarization at end of 250 GeV ramp: 53% • With incremental improvements <P> = 55 – 60% possible for next run: • Changes in source/LEBT/MEBT: +6% in <P> • Smaller emittance growth (24 → 18 mm): +8% in <P> • Small change in store energy: no P decay during store: +5% in <P> • Remaining pol. Loss during AGS (~15%) and RHIC (~15%) accel., to be studied with tracking simulations 7/10 15/22 11/16 P lifetime in store 19/28 Snake resonances: With jump quads<P> = 67.6 ± 1.0 % RH = 0.02 ± 0.02 Jump quads off time<P> = 62.6 ± 1.5 %RH = 0.07 ± 0.03 Run 9 working point Run 11 working point E.C. Aschenauer He-3 Workshop, BNL, September 2011

  8. Projections for p↑-p↑ 56 MHz SRFincremental changes polarized source upgradeelectron lens commissioning incremental changes(ex,y, es, DEstore, db/b…) Note1: assume 12 weeks of physics, 8 weeks of ramp-up, start at ¼ of max Note 2: last projections from 11 May 2010 still valid – reached peak performance goals for both polarized protons and heavy ions, will update after Run-11 Note 3: AnDY operation with ~10 pb-1/week after ramp-up E.C. Aschenauer He-3 Workshop, BNL, September 2011

  9. Electron Beam Ion Source (EBIS) (J. Alessi et al.) Jet/C-Polarimeters 12:00 o’clock eLenses 10:00 o’clock ANDY 2:00 o’clock RHIC PHENIX 8:00 o’clock RF 4:00 o’clock STAR 6:00 o’clock LINAC NSRL EBIS Booster ERL Test Facility AGS 860 m transfer line Tandems ions currently from electrostatic Tandem accelerators (~40 years,several upgrades) E.C. Aschenauer He-3 Workshop, BNL, September 2011

  10. Electron Beam Ion Source (EBIS) • 10 A electron beam creates desired charge state(s) in trap within 5 T superconducting solenoid • Accelerated through RFQ and linac, injected into AGS Booster • All ion species incl. noble gas, uranium and polarized 3He • Operated for NSRL with • He+, He2+, Ne5+,Ne8+, Ar11+, Ti18+,Fe20+ • Commissioning for RHICunder way • Work on 4x Au32+ increaseto design intensity2x from electron current,2x from transmission • Received U cathode • Tandem still availableas backup in 2012 E.C. Aschenauer He-3 Workshop, BNL, September 2011

  11. Optically Pumped Polarized H–source (OPPIS) Current OPPIS A. Zelenski, PST2009 ECR Rb-cell SonaNa-jet (H+) (H0) (H−) RHIC OPPIS produces reliably 0.5-1.0 mA polarized H- ion current. Polarization at 200 MeV: P = 80-85%. Beam intensity (ion/pulse) routine operation: Source - 1012 H-/pulse Linac- 5x1011 AGS - 1.8-2.0x1011 RHIC - 1.8x1011/bunch sc solenoid • 29.2 GHz ECR source used for primary H+ generation • source was originally developed for dc operation E.C. Aschenauer He-3 Workshop, BNL, September 2011

  12. Optically Pumped Polarized H– source (OPPIS) Upgraded OPPIS (Run-13) A. Zelenski • Goals:1. H− beam current increase to 10mA (order of magnitude)2. Polarization to 85-90% (~5% increase) • Upgrade components: • 1. Atomic hydrogen injector (collaboration with BINP Novosibirsk) • 2. Superconducting solenoid (3 T) • 3. Beam diagnostics and polarimetry Source Neutralizer Ionizer Rb-cell Sona Na-jet (H+) (H0) (H+) (H0) (H−) sc solenoid 10x intensity increase was demonstrated in a pulsed operation by using a very high-brightness Fast Atomic Beam Source instead of the ECR source E.C. Aschenauer He-3 Workshop, BNL, September 2011

  13. Polarized Deuterium • Polarized neutrons for RHIC and eRHICcould be in deuterons (d = 2H1+) or 3He2+ • d very difficult at high energy (i.e. RHIC) • Currently no technical solution for maintaining and rotating polarizeddeuterons (G = −0.14) in RHIC • Siberian snake with Bout= 33.5 T, Bin= 101.6 T Orbit excursion in snake for deuterons  W. MacKay, CAD MAC-05, 09/15/2010 E.C. Aschenauer He-3 Workshop, BNL, September 2011

  14. Polarized 3He Summary W. MacKay, CAD MAC-05, 09/15/2010 E.C. Aschenauer He-3 Workshop, BNL, September 2011

  15. Polarized 3He source R&D • Started working on 3He source (MIT – R. Milner, Mainz) • 3 possibilities discussed to use EBIS (A. Zelenski, J. Alessi et al.) • 3He↑ production outside EBIS limits on field gradients • 3He↑ production inside EBIS space and maintenance issues, P source measurement • Injection of 3He+↑ into EBIS • In all cases EBIS ionizes to 3H2+↑ • Aim for 2.5x1011 ions from EBIS, 1x1011/bunch in RHIC • Could collide 3He-3He or p-3He at gmax = 178(3He with 166.2 GeV/nucleon, p with 167.5 GeV) E.C. Aschenauer He-3 Workshop, BNL, September 2011

  16. Absolute Polarimeter (H jet) RHIC pCPolarimeters Siberian Snakes RHIC PHENIX (p) STAR (p) Siberian Snakes Spin Rotators Solenoid Snake LINAC BOOSTER Pol. Proton Source 500 mA, 400 ms AGS Warm Snake 200 MeV Polarimeter AC Dipole AGS pC CNI Polarimeter Cold Snake RHIC and Polarimetry ANDY(p) E.C. Aschenauer He-3 Workshop, BNL, September 2011

  17. RHIC Polarimetry • Polarized hydrogen Jet Polarimeter (HJet) • Source of absolute polarization (normalization to other polarimeters) • Slow (low rates  needs lo-o-ong time to get precise measurements) • Proton-Carbon Polarimeter (pC) • Very fast  main polarization monitoring tool • Measures polarization profile (polarization is higher in beam center) • Needs to be normalized to HJet • Local Polarimeters (in PHENIX and STAR experiments) • Defines spin direction in experimental area • Needs to be normalized to HJet All of these systems are necessary for the proton beam polarization measurements and monitoring E.C. Aschenauer He-3 Workshop, BNL, September 2011

  18. RHIC Jet Results-2011 Beam Polarisation at 250 GeV Analyzing Power 250 GeV 100 GeV 24 GeV Beam Polarization decay through the fill Measured beam polarization at injection: Blue Beam: 0.61 +/- 0.043 Yellow Beam: 0.65 +/- 0.048 E.C. Aschenauer He-3 Workshop, BNL, September 2011

  19. RHIC pCResults-2011 24 GeV 250 GeV Analyzing power flat 100GeV  250 GeV 100 GeV E.C. Aschenauer He-3 Workshop, BNL, September 2011

  20. RHIC pC Results: Polarization Profile If polarization changes across the beam, the average polarization seen by Polarimeters and Experiments (in beam collision) is different H-Jet pC Collider Experiments ~1 mm 6-7 mm x=x0 P1,2(x,y) – polarization profile, I1,2(x,y) – intensity profile, for beam #1 and #2 E.C. Aschenauer He-3 Workshop, BNL, September 2011

  21. RHIC pC Results: Polarisation Profile Injection factor 2 increase 250 GeV polarisation profile for ramp up – down measurment For impact for machine tuning E.C. Aschenauer He-3 Workshop, BNL, September 2011 100

  22. Polarization evolution in AGS and RHIC • Polarization loss from intrinsic resonances: polarization lost at edge of beam → polarization profile • Impact of polarization profile on beam polarization at collisions: • For Rx ≈ Ry and small: P0 = <P> (1+<R>)2; Pcoll. = <P> (1+½<R>) • Note that P0, the polarization of the core particle, should be equal to the maximum achievable polarization. E.C. Aschenauer He-3 Workshop, BNL, September 2011

  23. Performance over the years • Systematic Uncertainties: Run9 500 GeVblue: 8.3% Run9 500 GeVyell: 12.1% Run9 200 GeVblue: 4.7% Run9 200 GeVyell: 4.7% Run8 200 GeVblue: 4.2% Run8 200 GeVyell: 7.2% Run6 200 GeVblue: 4.7% Run6 200 GeVyell: 4.8% Run6 62 GeVblue: 7.2% Run6 62 GeVyell: 9.3% Run5 200 GeVblue: 5.9% Run5 200 GeVyell: 6.2% Run4 200 GeVblue: 12.0% Run4 200 GeVyell: 16.6% Run3 200 GeVblue: 18.6% Run3 200 GeVyell: 16.8% Best value till today ~5% E.C. Aschenauer He-3 Workshop, BNL, September 2011

  24. The Physics Case E.C. Aschenauer He-3 Workshop, BNL, September 2011

  25. DG SqLq Lg SqDq SqDq Lg SqLq dq DG dq How do the partons form the spin of protons Is the proton looking like this? HP-8 2013 HP-13 2015 HP-12 2013 “Helicity sum rule” gluon spin Where do we stand solving the “spin puzzle” ? angular momentum total u+d+s quark spin E.C. Aschenauer He-3 Workshop, BNL, September 2011

  26. More insights to the proton Transversity distribution function dq(x) Single Spin Asymmetries Unpolarized distribution function q(x), G(x) beyond collinear picture Explore spin orbit correlations Sivers distribution function Boer-Mulders distribution function Correlation between and Helicity distribution function Dq(x),DG(x) Correlation between and Correlation between and E.C. Aschenauer He-3 Workshop, BNL, September 2011

  27. u d Dq: W Production Basics Since W is maximally parity violating W’s couple only to one partonhelicity large Δuand Δdresult inlarge asymmetries. No Fragmentation ! Similar expression for W- to get Δ and Δd… E.C. Aschenauer He-3 Workshop, BNL, September 2011

  28. expectations for ALe in pp collisions de Florian, Vogelsang t large u large t large u large strong sensitivity to limited sensitivity to E.C. Aschenauer He-3 Workshop, BNL, September 2011

  29. RHIC: AL for W bosons • RHIC: can detect only decay leptons; • lepton rapidity most suited observable • strong correlation with x1,2 de Florian, Vogelsang, arXiv:1003.4533 Δχ2 = 2% uncertainty bands of DSSV analysis • allows for flavor separation for 0.07 < x < 0.04 Δχ2 = 2% uncertainty bands with RHIC data E.C. Aschenauer He-3 Workshop, BNL, September 2011

  30. ALW: Future Possibilities ALW: He3-p @ 432 GeV ALW: pp @ 500 GeV phase 2 of pp2pp@STAR can separate scattering on n or p E.C. Aschenauer He-3 Workshop, BNL, September 2011 • Can we increase p-beam energy? • 325 GeV: factor 2 in sW • access to lower x for Dg(x) • Increased beam-energy and polarized He-3 beam  full flavor separation

  31. Critical √s of W cross section Lets see what is possible Main issues: • Quench performance of magnets (DX, arc dipoles and quads, IR quads) • Crossing angles at IPs and luminosity • Polarization • Current feed-throughs • Power supplies and transformers • Dump kicker (strength, pre-fires) • Reliability generally reduced at higher energies Report: W. MacKay BNL C-A/AP/422 E.C. Aschenauer He-3 Workshop, BNL, September 2011

  32. Energy upgrade – W. MacKay Conclusion: • 10% increase to 275 GeVfeasible with current magnets about 20 DX, 10 other training quenches, more cooling at some current leads • Requires some hardware upgrades (power supplies) • Effect on polarization still needs study • Energies >275 GeV require too many training quencheshundreds of arc dipole training quenches alone for 325 GeV estimated # of training quenches observed quenches in arc dipoles acceptance test, 62 DRG E.C. Aschenauer He-3 Workshop, BNL, September 2011

  33. Quantum phase-space tomography of the nucleon 3D picture in momentum space 3D picture in coordinate space transverse momentum generalized parton distributions dependent distributions  exclusive reaction like DVCS Wigner Distribution W(x,r,kt) Join the real 3D experience !! TMDs GPDs d3r d2ktdz u-quark Polarized p Polarized p d-quark E.C. Aschenauer He-3 Workshop, BNL, September 2011

  34. left right Transverse single-spin asymmetries FNAL s=19.4 GeV BRAHMS@RHIC s=62.4 GeV BNL AGS s=6.6 GeV ANL ZGS s=4.9 GeV Left -Right p0 Phys. Rev. Lett. 101 (2008) 222001 Big single spin asymmetries in pp !! Naive pQCD (in a collinear picture) predicts AN ~ asmq/sqrt(s) ~ 0 What is the underlying process? Sivers or Twist-3 or Collins or .. Do they survive at high √s? Is pt dependence as expected from p-QCD? • YES E.C. Aschenauer He-3 Workshop, BNL, September 2011

  35. What do we know: Twist-3 vs. TMD Intermediate QT Q>>QT/pT>>LQCD Transverse momentum dependent Q>>QT>=LQCD Q>>pT Collinear/ twist-3 Q,QT>>LQCD pT~Q Efremov, Teryaev; Qiu, Sterman Siversfct. critical test for our understanding of TMD’s and TMD factorization QCD: DIS: attractive FSI Drell-Yan: repulsive ISI QT/PT LQCD Q QT/PT << << E.C. Aschenauer He-3 Workshop, BNL, September 2011 SiversDIS = -SiversDY

  36. New Global Fit Parameterization: A. Prokudin, Z.-B. Kang shape ala DSSV node if ηq>0 Data-Input: HERMES and COMPASS SIDIS & STAR p0 Anselmino et al. 2009 Impact on DY AN need to measure DY xf < 0.3 E.C. Aschenauer He-3 Workshop, BNL, September 2011

  37. The long term future future of pp@RHIC AN in 3He-proton collisions Siversfcts. for u and d quarks opposite in sign and slightly larger for d quarks expectations for Drell Yan Z. Kang @ 2010 Iowa RSC meeting • u <-> disospin rotation leads to different signs for AN for protons and neutrons • asymmetries for neutrons are larger (due to electric charges) proton caveat: does not yet include possibility of nodes in Sivers function neutron expectations for AN (pions) • similar effect for π± (π0 unchanged) • this time computed within twist-3 formalism • here, effect due to favored/unfavored fragmentation 3He: helpful input for understanding of transverse spin phenomena E.C. Aschenauer He-3 Workshop, BNL, September 2011

  38. From RHIC to eRHIC Jet/C-Polarimeters 12:00 o’clock eLenses 10:00 o’clock eRHIC-Detector & Polarimeters 12:00 o’clock ANDY 2:00 o’clock RHIC eRHIC e PHENIX 8:00 o’clock RF 4:00 o’clock e STAR 6:00 o’clock LINAC NSRL EBIS Booster ERL Test Facility AGS Tandems E.C. Aschenauer He-3 Workshop, BNL, September 2011

  39. p What is eRHIC RHIC Existing = $2B Electron accelerator to be build protons Polarized protons 50-250GeV electrons e- Unpolarized and polarized leptons 5-20 (30)GeV Light ions (d,Si,Cu) Heavy ions (Au,U) 50-100GeV/u e- e+ Polarized light ionsHe3 166 GeV/u 70% e-beam polarization goal polarized positrons? Center mass energy range: √s=30-200GeV; L~100-1000xHera longitudinal and transverse polarization for p/He3 possible E.C. Aschenauer He-3 Workshop, BNL, September 2011

  40. Photon: DF Quark: FF Hadron: Deep Inelastic Scattering Important kinematic variables: Collider: q cross section: Spin 1 E.C. Aschenauer He-3 Workshop, BNL, September 2011

  41. PLB 647 (2007) 330 World data on inclusive DIS • New data from COMPASS, • HERMES & JLab very precise • high x-behaviour consistent with • A1 with x1 • A1d consistent with zero • for x < 0.05 E.C. Aschenauer He-3 Workshop, BNL, September 2011

  42. World data on inclusive DIS Combine p and d to get n: or 3He • What can we learn on the PDFs E.C. Aschenauer He-3 Workshop, BNL, September 2011

  43. polarized DIS and impact on Δg(x,Q2) strategy to quantify impact: global QCD fit with realistic toy data W2 > 10GeV2 ECA+M. Stratmann • DIS data sets produced for stage-1 [5x50, 5x100, 5x250] and 20x250 • DIS statistics “insane” after 1 month of running (errors MUCH smaller than points in plots) E.C. Aschenauer He-3 Workshop, BNL, September 2011

  44. The Bjoerken Sum Rule One of the best known quantities in pQCD Calculated in pQCD Currently measured to 10% EIC could provide a 1-2% measurement, if the we can measure the beam polarization to 1-2% E.C. Aschenauer He-3 Workshop, BNL, September 2011

  45. Quantum phase-space tomography of the nucleon 3D picture in momentum space 3D picture in coordinate space transverse momentum generalized parton distributions dependent distributions  exclusive reaction like DVCS Wigner Distribution W(x,r,kt) Join the real 3D experience !! TMDs GPDs d3r d2ktdz u-quark Polarized p Polarized p d-quark E.C. Aschenauer He-3 Workshop, BNL, September 2011

  46. angle of hadron relative to initial quark spin (Sivers) Sivers Collins Azimuthal angles and asymmetries angle of hadron relative to final quark spin (Collins) EIC-Lumi: 1 month @ 20 GeV x250 GeV Sivers MosteRHIC measurements systematics limited  Polarization uncertainty SIDIS allows to study subprocessesindividually eHe3 and ep allow full flavour separation E.C. Aschenauer He-3 Workshop, BNL, September 2011 Thomas Burton

  47. ✓ Summary Pol. Source ✓ ✓ Polarimetry All ingredients are there so lets do it Pol. RHIC Physics ✓ eRHIC ✓ E.C. Aschenauer He-3 Workshop, BNL, September 2011

  48. BACKUP E.C. Aschenauer He-3 Workshop, BNL, September 2011

  49. From RHIC to eRHIC eRHIC staging: All energies scale proportionally by adding SRF cavities to the injector and two linacs and cranking power supplies up 27.55 GeV 22.65 GeV 17.75 GeV 27.55 GeV 3rd detector 12.85 GeV 7.95 GeV Beam dump 3.05 GeV Coherent e-cooler 0.6 GeV 30 GeV Polarized e-gun 25.1 GeV 20.2GeV 15.3 GeV 10.4 GeV ePHENIX 5.5 GeV 100m |--------| 30 GeV eSTAR 30 GeV Vertically separated recirculating passes. # of passes will be chosen to optimize eRHIC cost E.C. Aschenauer He-3 Workshop, BNL, September 2011 Gap 5 mm total 0.3 T for 30 GeV

  50. eRHIC luminosity Luminosity for 30 GeV e-beam operation will be at 20% level Hourglass effect is included E.C. Aschenauer He-3 Workshop, BNL, September 2011

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