Probing the Color Gauge Link via Heavy Quark TSSA in p+p CollisionsMing X. LiuLos Alamos National Lab

INT Spin Workshop 11/2010

A new Experimental Test of color dynamics in hard scattering

TSSA for Open (anti)charm, J/Psi and DY Test color structures for quark and anti-quark Experimental opportunity: RHIC and other future Exps

An experimentalists point of approach

*Ming X. Liu INT Workshop*Drawing from D. Sivers @Santa Fe Polarized Drell-Yan Workshop Dinner 10/31-11/1, 2010

Ming X. Liu INT Workshop

Color Flow in DY and DISThe sign change a new fundamental test of color gauge formalismCharm TSSA could provides a new independent experimental test of the underlying physics Twist-3: sign change from gluonic-pole in hard parts

In the overlapped region consistent description **Ming X. Liu INT WorkshopCollins 02Ji, Qiu, Vogelsang, Yuan 06Bacchetta, Boer, Diehl, Mulders 08

Ming X. Liu INT Workshop

Nice things about heavy quarksExperimentally tag Fermion and anti-Fermion

Theoretically clean to use pQCDMQ >> QCDHard fragmentation*Ming X. Liu INT Workshop*

Ming X. Liu INT Workshop

Ming X. Liu INT Workshop*Do we understand the physics?The Challenge of Too Large

PRD65, 092008 (2002)PRL36, 929 (1976)ZGS 12 GeV beamAGS 22 GeV beamFNAL 200 GeV beamPLB261, 201 (1991)PLB264, 462 (1991)RHIC 20,000 GeV beamNon-Perturbative cross sectionPerturbative cross sectionPRL (2004)Large Transverse Single Spin Asymmetry (SSA) in forward meson production persists up to RHIC energy.*

Ming X. Liu INT Workshop

Color Interaction and TSSADo we understand the underlying physics?the Sivers asymmetry, for example What can we learn more from future data?DY, charm, direct-photon

We are colliding hadrons, not partons!**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

Gamberg, Kang 2010 Generalizing GPM with modified hard cross sections (gluonic-pole cross sections)PRL 99 (2007) A. Bacchetta et al, PRD 72 (2005) A. Bacchetta, C.J. Bomhof, P.J.Mulders, F.Pijlman**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

Charm and anti-Charm TSSA and Color StructureQuark and anti-Quark have different color structure in hard scatterings

Experimentally Charm and anti-Charm can be cleanly identified,

AN(charm) provide new insight to the underlying physics of TSSADirectly test the different color structure for quark and anti-quark **A new clean experimental test of the color couplingto quark vs antiquark in hard scatterings!Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

TSSA in Heavy Quark ProductionKang, Qiu, Vogelsang, Yuan, PRD 2008**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

**Ming X. Liu INT WorkshopOpen Charm TSSA in Twist-3 Approach

Ming X. Liu INT Workshop

TSSA in Charm Production at Low Energy (I)Low energy Initial state interactions

Final state interactions*Ming X. Liu INT Workshop*F. Yuan and J. Zhou PLB 668 (2008) 216-220

Ming X. Liu INT Workshop

Heavy Quark TSSA at Low Energy (cont.)Twist-3 quark-gluon correlation fun. Different color factors for charm and anti-charmCharmanti-CharmInitial stateF. Yuan and J. Zhou PLB 668 (2008) 216-220**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

JPARC p+pGSI: p+pbar**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

*

Sensitive to gluon Sivers function * probe gluons orbital angular momentum?-- Minimize Collins effects * heavy flavor production dominated by gluon gluon fusion at RHIC energy Pythia 6.1 simulation (LO)

* gluon has zero transversity

Tri-gluon correlation functions

Also sensitive to J/ production mechanisms and QCD dynamics

Heavy Flavor TSSA @RHICOpen CharmJohann Riedl, SPIN2008

Heavy Quark SSA at High Energy (II)Twist-3 tri-gluon correlation Consequence of different color factors for charm and anti-charmKang et al 2008Koike et al 2010**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

The Physics Goals

Experimental Study of the Color Flow via Open Heavy Quark TSSACurrent understanding of TSSA based on the color gauge invariant QCD formalismTwist-3, modified GPM Expect significant difference between AN(c) and AN(c-bar)

The process dependence of TSSA can be tested experimentallyDY vs DISCharm (quark) vs anti-charm (anti-quark)Other processes .. **Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

Experimental ProspectsRHIC @high energyOther facilities @low energy JPARCGSI/FAIRFermilabEIC**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

Open Charm Production in p+pwith PYTHIA (LO) **Ming X. Liu INT WorkshopE906RHIC 62GeVJAPRCRHIC 200 GeV

Ming X. Liu INT Workshop

Charm Production p+p @200GeV At low pT, g+g dominates**Ming X. Liu INT WorkshopLONLO

Ming X. Liu INT Workshop

More on Open Charm ProductionFixed targets vs NLOCollider mode @RHICPRL 95, 122001 (2005) M. Cacciari, P. Nason, R. VogtEPJ C 52, 987 (2007) J. Riedl, A. Schafer, M. Stratmann**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

*D meson production dominated by gluon-gluon fusion at RHIC energySensitive to gluon Sivers effectAN measured for muons from D decaySmear by decay kinematicsAnselmino et al, PRD 70, 074025 (2004)Gluon Sivers=0Gluon Sivers=MaxCalculations for D mesonsD (m-)Forward Open (anti)Charm AN

*TSSA and J/ Production J/ TSSA is sensitive to the production mechanisms Assuming a non-zero gulon sivers function, In pp scattering, TSSA vanishes if the pair are produced in a color-octet model but survives in the color-singlet model Feng Yuan, Phys. Rev D78, 014024(2008)In Collinear higher twist approach, the relation is not quiet simple. There are partial but not full cancellation of terms. Z. Kang

*PHENIX DetectorCentral Arm || < 0.35

Drift Chamber (DC) PbGl and PbSc Ring Imaging Cherenkov Detector (RICH) Pad Chambers (PC) Time Expansion Chamber (TEC)

Global Detectors (Luminosity,Trigger)

BBC ZDC

Muon Arms 1.2 < || < 2.4 Muon tracker (MuTr) Muon Identifier (MuID)

Years [GeV]Recorded LPol [%]FOM (P2L)2006 (Run 6)2002.7 pb-151700 nb-12008 (Run 8)2005.2 pb-1 461100 nb-1

*J/ Measurements in the Muon and Central ArmsarXiv: 1009.4864

*Asymmetries were obtained as a function of J/Psi Feynman-x, with a value of -0.086 0.026 (stat.) 0.003 (sys.) in the forward region. X. Wang, SPIN2010, arXiv: 1009.4864- Suggests possible non-zero tri-gluon correlation functions in transversely polarized protons.- If well defined in this reaction, the results suggests non-zero gluon Sivers distribution functions. J/ AN at Forward Rapidity

*NRQCD and J/ ProductionTheoretical predictions of J/ production at RHIC are in good agreement with the PHENIX data: COM process dominantPRD 68 (2003) 034003 G. Nayak, M. Liu, F. CooperPRL 93 (2004) 171801 F. Cooper, M. Liu, G. Nayak

*NRQCD and J/ PolarizationNRQCD failed on J/ polarization.J/ production mechanism is still an open question. Very active field of theoretical study

Near Future Prospects

PHENIX Silicon VTX Upgrades: by 2011Ming X. Liu Seminar@UNM*Precision Charm/Beauty MeasurementsBJ/, Drell-Yan,

10/26/10

Ming X. Liu Seminar@UNM

Charm SSA to Probe Gluon Sivers Distribution*Kang, Qiu, Yuan, Vogelsang, Phys. Rev. D 78,114013(2008) D meson Single-Spin Asymmetry: Production dominated by gluon-gluon fusion Sensitive to gluon Sivers distribution PHENIX-2006 data ruled out the max. gluon Sivers Much improved results expected with VTX detectorsMing X. Liu INT Workshop*

Ming X. Liu INT Workshop

A few Observations and CommentsTwist-3 and Generalized TMD Parton ModelColor gauge approach

Quark sector: some knowledgeQuark Sivers and Collins functionsTwist-3 quark-gluon correlation functions

Gluon sector: largely unknownGluon Sivers function(s)??Twist-3 tri-gluon correlation functions

Next experimental step for p+p Heavy quark probe!Directly access the color charge coupling to quark and anti-quarkMulti probes in a wide kinematic range High luminosity polarized fixed target Drell-Yan and Charm experiment?

It is all about the color flow in hard scatteringTSSA @RHIC-SPINp/d+A @RHIC Jlab-12, EIC**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

Charm TSSA @EICOpen charmJ/PsiNeed model calculations*Ming X. Liu INT Workshop*Kang and Qiu PRD (2008)

Ming X. Liu INT Workshop

EIC: J/Psi TSSA (I)TSSA could be closely connected to J/Psi production mechanismsF. Yuan PRD 70, 074025**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

EIC: J/Psi SSA (II)Color octet channel**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

New Idea: High Luminosity Polarized Fixed Target p+p?Drell-YanOpen charm@ low s*Ming X. Liu INT Workshop*

Ming X. Liu INT Workshop

Ming X. Liu Seminar@UNM*Example (I): E906 Drell-YanPolarized DY possibility:Polarized targets Polarize the Main Injector Or both120 GeV proton beamXBeamXTarget10/26/10

Ming X. Liu Seminar@UNM

Ming X. Liu Seminar@UNM*UVA/J-Lab/SLAC Polarized proton/deuteron targetPolarized NH3/ND3 targetsDynamical Nuclear Polarization Operate at 5 T and 1 K. Pol ~ B/TUsed with high beam intensities up to ~100 nALarge capacity pumpsPolarizations: p > 90%, d ~ 50%

Able to handle high luminosity up to ~ 1035 (Hall C) ~ 1034 (Hall B)

D. Crabb MENU1010/26/10

Ming X. Liu Seminar@UNM

Ming X. Liu Seminar@UNM*Expected DY AN Sensitivity @120 GeV.Target 6 cm NH3 1019 proton10/26/10Also open charm and J/psi

Ming X. Liu Seminar@UNM

Summary and OutlookExperimental confirmation (or disproval) of color flow dynamics in hard scattering is a critical step toward understanding the mechanisms of SSADrell-YanCharm vs anti-Charm

Future experimental prospects exciting opportunity!RHIC, high energy EICPolarized fixed targets, low energy**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

Backup *Ming X. Liu INT Workshop*

Ming X. Liu INT Workshop

*Ming X. Liu INT Workshop*Critical Role of VTX/FVTX for Drell-Yan and Open CharmTracking muons with MuTr+FVTXPrompt muons from DYDisplaced tracks from /K and heavy quark decays

DCA < 1 cut: Increase DY/bb ~ 5

Ming X. Liu INT Workshop

Ming X. Liu Seminar@UNM**Example (II): Polarized DY w/ Fixed Target @RHIC ?Polarized fixed target DY exp. with extracted polarized proton beams:Fixed Target DY Exp. @Beam Dump

High density LH2/LD2 targetHigh density polarized targets3Map out x-dep.- 250 GeV proton beams- Pol up to 70%10/26/10

Ming X. Liu Seminar@UNM

Ming X. Liu Seminar@UNM*Fixed Target @RHIC ?Beam dump experiment: dimuon channelParasitic modeSignificant beams still left at the end of a store (~50%)Cycle time ~8hrDedicated fixed targetCycle time ~ 1hrDimu x-section @ 250 GeV (M>4) ~20pb

TargetsE906-like unpolarized LH2 target51cm LH2 (2.1x1024/cm2)Can handle L ~ 1x1036cm-2s-1Polarized solid targetUVA/J-Lab/SLAC: L ~1035cm-2s-1AdvantagesPolarized beams(polarized) targetsHigher Energy and large x-coverageHigh luminosity10/26/10

Ming X. Liu Seminar@UNM

Ming X. Liu Seminar@UNM*DY AN Sensitivity @250 GeV Fixed Target4.5

Open charm at fixed target (cross section)Charm cross section by fixed target experiments are reasonably reproduced by LO pQCD event generator (PYTHIA) with large K-factor, or by NLO pQCD calculation (HVQMNR). Note that pQCD may or may not be applicable to charm production because charm mass is small (~1.5GeV)In the left figure, world pi+N data and p+N data are compared with PYTHIA calculation. The s1/2 dependence of the calculation mainly reflects the underlying PDF. s1/2(GeV)scc in pN,pN

Charm production *Ming X. Liu INT Workshop*

Ming X. Liu INT Workshop

Ming X. Liu Seminar@UNM*Proton Efficiency: Collider vs Fixed Target ModeDesign value: 2x1011x100 = 2 x 1013 proton per store per ringCollision rate ~ 10 MHzNum. of collisions per store10M x 3600sec x 8 hr = 2.9 x 1010Fract. of ps used = 3 x1011 / 2 x 1013 = 1.5 x 10-2In the fixed target mode, for a ~20% interaction length, we can use ~20% of the protons from the beam0.2/ 1.5 x 10-2 = 13x gain in luminosityCenter of Mass Energies for p+pCollider mode: sqrt(s) = 500 GeVFixted T mode: sqrt(s) = 22 GeV

10/26/10

Ming X. Liu Seminar@UNM

Color Flow in Twist-3Kang @RBRC workshop 2010**Ming X. Liu INT Workshop

Ming X. Liu INT Workshop

Generalized Parton ModelAssume TMD factorization**Ming X. Liu INT WorkshopAnselmino et al.TMD factorization breakdown a failure or an opportunity? Mulders, Xiao.. @RBRC workshop 2010

Ming X. Liu INT Workshop

*What about gluon***