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The J-PARC Facility and Ideas for TMD Measurements

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The J-PARC Facility and Ideas for TMD Measurements Powered By Docstoc
					The J-PARC Facility and Ideas
   for TMD Measurements
          ECT* Workshop
           June 15, 2007
     Yuji Goto (RIKEN/RBRC)
                 J-PARC at Tokai


KAMIOKA
                    295 km                        JAEA
                                                 JAERI
                                                         Tokai
                                         1 hour
                                         KEK

                                        Tsukuba
                                TOKYO
                                               NARITA




 June 15, 2007        ECT* Workshop                              2
                       J-PARC facility
                                                          Hadron Beam Facility
                   Materials and Life Science
                     Experimental Facility

      Nuclear
   Transmutation

                                                             500 m



                                                              Neutrino to
                                                              Kamiokande



                                  3 GeV Synchrotron        50 GeV Synchrotron
                    Linac
                                     (25 Hz, 1MW)               (0.75 MW)
                   (330m)

                                J-PARC = Japan Proton Accelerator Research Complex


                      Joint Project between KEK and JAEA

June 15, 2007                    ECT* Workshop                                       3
                   J-PARC facility
     – The budget for about 2/3 of the entire project has
       been approved by the Japanese government from
       JFY2001 as phase 1
     – Phase 1 consists of major accelerator components
       and a part of experimental facilities




June 15, 2007             ECT* Workshop                     4
                  J-PARC parameters
• 50 GeV beam
     –   repetition 3.4 ~ 5 (or 6) sec
     –   flat top width 0.7 ~ 2 (or 3) sec
     –   linac energy 400 MeV
     –   3.31014 ppp, 15 A
     –   beam power 750 kW
• 30 GeV beam (phase-1)
     – linac energy 180 MeV
     – 21014 ppp, 9 A
     – beam power 270 kW




June 15, 2007                 ECT* Workshop   5
                      J-PARC schedule




                                                       first beam for the nuclear
                                                       -particle experiments in
                                                       JFY2008
                                                      first beam for the
                                                      neutrino experiments
                                                      in JFY2009

•    June, 2007: Completion of civil construction of the Hadron Hall
•    December, 2007: Start of dry run of the main-ring synchrotron
•    May, 2008: Start of beam commissioning of the main-ring synchrotron
•    December 2008: Acceleration to 30 GeV and the first beam to the
     Hadron Hall
    June 15, 2007                ECT* Workshop                             6
                                  RCS


     n
                                MLSF




Bird’s eye photo in Nov. 2006
  June 15, 2007                 ECT* Workshop
                                                Hd   7
  Hadron experimental hall (phase 1)
  beamlines for secondary beam experiments at the beginning of the phase1

 Experimental
 Area
                             Test
                             Beam


      A-Line
                                                               Beam
                                                               Dump
                                                             (on the guide
                                                                  rail
                                                              for Phase 2)




                                      area for primary beam experiments


June 15, 2007                  ECT* Workshop                                 8
        Dimuon experiment at J-PARC
• Proposal and collaborators




June 15, 2007       ECT* Workshop     9
June 15, 2007   ECT* Workshop   10
        Dimuon experiment at J-PARC
• Drell-Yan
     – the simplest process in hadron-hadron reactions

        DIS                              Drell-Yan



          • no final-state effect
          • no polarized Drell-Yan experiment done yet
     – rich programs
          •     unpolarized and polarized program
          •     flavor asymmetry of the sea-quark distribution
          •     orbital angular momentum in the nucleon
          •     transversity, etc.



June 15, 2007                       ECT* Workshop                11
                Dimuon experiment
• Fermilab E866 experiment
     – flavor asymmetry of the seq quark distribution

                                           pd 1  d ( x2 ) 
                                                ~ 1         
                                          2 pp
                                                 2  u ( x2 ) 


                                          with CTEQ5M
                                              0.35
                                          
                                          0.015
                                                     dx[d ( x)  u ( x)]
                                           0.0803  0.011
                                           1
                                           dx[d ( x)  u ( x)]
                                          0

                                           0.118  0.012

June 15, 2007             ECT* Workshop                                    12
                Dimuon experiment
• Fermilab E906 experiment
     – similar experiment of E866 at lower energy 120 GeV
       with Tevatron main injector to cover higher-x region
     – construction 2007 – 2008 (or 2009) – not yet started
     – beam time 2009 – 2010 (or 2010 – 2011)
• apparatus
     – partially to be used at J-PARC




June 15, 2007             ECT* Workshop                       13
        Dimuon experiment at J-PARC
• Possible layout of the hadron hall




June 15, 2007        ECT* Workshop     14
        Dimuon experiment at J-PARC
• Unpolarized program
     – proton beam on proton and deuterium target




June 15, 2007            ECT* Workshop              15
                  Spin physics at J-PARC
• Polarized Drell-Yan
     – ALL measurement
          • flavor asymmetry of sea-quark polarization



                                                                             GS-C
                                                                             GS-A
                                                                             GRSV



                chiral quark soliton
                model prediction


                                              120-day run
                                              75% polarization for a 51011 protons/spill
                                              polarized solid NH3 target, 75% hydrogen
                                              polarization and 0.15 dilution factor
June 15, 2007                          ECT* Workshop                                16
                Spin physics at J-PARC
• G will be made clear by RHIC and pol-DIS
  experiments soon…
• Orbital angular momentum in the nucleon
     – in hadron-hadron reaction, no direct connection
       between measurement and theory (yet)
     – but, any partonic transverse motion and correlation
       should be related
          • Sivers effect
          • higher-twist effect
     – ALL measurement may also sensitive at high-xF…
          • Feng Yuan’s calculation with Lz = 1 component… [Harut
            Avakian, Feng Yuan, et al. arXiv:0705.1553.]



June 15, 2007                     ECT* Workshop                     17
                  Polarized Drell-Yan
• AN measurement
     – Ji, Qiu, Vogelsang, and Yuan
          • PRD 73, 094017 (2006)
          • sensitive to higher-twist effect at high qT ~ Q
          • Sivers effect and higher-twist effect provide the same
            description of SSA on Drell-Yan at moderate qT: QCD << qT
            << Q
          • similar for SSA on semi-inclusive DIS: hep-ph/0604128
     – Sivers function in Drell-Yan is expected to have a
       sign opposite to that in DIS




June 15, 2007                  ECT* Workshop                             18
                      Polarized Drell-Yan
   • AN measurement

                                  4 < M+- < 5 GeV
                                  integrated over qT




Theory calculation by Ji, Qiu, Vogelsang        1000 fb-1 (120-day run), 75%
and Yuan based on Sivers function fit of        polarization, no dilution factor
HERMES data (Vogelsang and Yuan:
PRD 72, 054028 (2005))


   June 15, 2007                    ECT* Workshop                                  19
      Polarized (and unpol.) Drell-Yan
• ATT measurement
     – transversity            ATT  q( x1 )q( x2 )
• Boer-Mulders function by unpol. Drell-Yan
     – angular distribution of unpolarized Drell-Yan

 1  d   3                                 n 2           
               1   cos    sin 2 cos   sin  cos 2 
                             2
 
   d    4                               2             
     – correlation between transverse quark spin and quark
       transverse momentum
                                                                            
                                     ˆ
                                   ( P  k )  Sq q                    ˆ
                                                                       ( P  k )  Sq
     N ( )  h1 q ( x1 , k  ) 
                             2
                                                   h1 ( x2 , k 2 ) 
                                         M                                   M


June 15, 2007                       ECT* Workshop                                    20
        Polarized (and unpol.) Drell-Yan
  • Boer-Mulders function by unpol. Drell-Yan
    – Lam-Tung relation    1    2n
            • reflect the spin-1/2 nature of quarks
       – violation of the Lam-Tung relation suggests non-
         perturbative origin     n  ,     n


                               With Boer-Mulders function h1┴:
                               ν(π-Wµ+µ-X)~valence h1┴(π)*valence h1┴(p)
                               ν(pdµ+µ-X)~valence h1┴(p)*sea h1┴(p)




L.Y. Zhu,J.C. Peng, P. Reimer et al., hep-ex/0609005
  June 15, 2007                    ECT* Workshop                       21
                  Towards the goal
• 30 GeV  50 GeV
• unpolarized  polarized target  polarized beam
  – polarized beam study by BNL & KEK groups
  – possible locations of partial snakes in MR




        First 30% snake                   Second 30% snake




 June 15, 2007            ECT* Workshop                      22
                             Physics at 30 GeV
• J/
     – gluon fusion or quark-pair annihilation
     – quark-pair annihilation dominant
              • must be confirmed experimentally…
              • similar physics topics as Drell-Yan process
                                      calculations by color-evaporation model



         eq         



     q                  l
              J/
          V
         gq      g lV
     q                  l
June 15, 2007                       ECT* Workshop                               23
                 Physics at 30 GeV
                                    J-PARC: Elab = 50 GeV
• SSA measurement of open
  charm production
  – no single-spin transfer to the
    final state
  – sensitive to initial state
    effect: Sivers effect
  – collider energies: gluon-
    fusion dominant
      • sensitive to gluon Sivers RHIC: s = 200 GeV
        effect
  – fixed-target energies: quark-
    pair annihilation dominant
      • sinsitive to quark Sivers
        effect
                                  M. Anselmino, U. D’Alesio, F. Murgia, et al.
 June 15, 2007             ECT* Workshop                                24
                             Summary
• J-PARC will start operation at 30 GeV for hadron-hall
  users in JFY 2008
• Possible high-momentum beam-line for primary beam
  users in JFY 2011
• Proposal of the dimuon experiment has been submitted
  to the J-PARC PAC
     – deferred at the 1st J-PARC PAC, June 30 – July 2, 2006
     – to be resubmitted for the 3rd J-PARC PAC, July 6 – 7, 2007 to
       get a stage-1 approval (scientific approval)
• It has rich unpolarized and polarized programs
     –   flavor asymmetry of the sea-quark distribution
     –   orbital angular momentum in the nucleon
     –   transversity, etc.
     –   J/ and charm physics with 30 GeV beam
• Your participation and collaboration, suggestions of
  measurements and theoretical calculations are very
  welcome
June 15, 2007                   ECT* Workshop                          25
Backup Slides
                            J-PARC facility
September, 2005




  Hadron Experimental
        Facility
   Number of Users: about 600
       (about 1/3 from Japan)

   June 15, 2007                ECT* Workshop   27
  Hadron experimental hall (phase 1)
    beamlines for secondary beam experiments at the beginning of the phase1

  Experimental
  Area
                               Test
                               Beam


        A-Line
                                                                 Beam
                                                                 Dump
                                                               (on the guide
                                                                    rail
                                                                for Phase 2)




                                        area for primary beam experiments

June 15, 2007                   ECT* Workshop                               28
                  Dimuon experiment
  • Fermilab E866/NuSea
       – closed geometry

Fermilab Elab = 800 GeV
2×1012 protons / 20 sec




  June 15, 2007            ECT* Workshop   29
                Experimental apparatus
 – based on the Fermilab spectrometer for 800 GeV, the length can be
   reduced but the aperture has to be increased
 – two vertically bending magnets with pT kick of 2.47 GeV/c and 0.5
   GeV/c
 – tracking is provided by three stations of MWPC and drift chambers
 – muon id and tracking are provided
 – 2x1012 50 GeV protons/spill

                 tapered copper beam dump and
                 Cu/C absorbers placed within the first magnet




June 15, 2007                    ECT* Workshop                    30
                  Simulation studies
• Expected Drell-Yan
  counts for a two-month
  p+d run at 50 GeV
   – 2x1012 protons/spill
   – 50-cm long liquid
     deuterium target
   – assume 50 percent
     overall efficiency




  June 15, 2007             ECT* Workshop   31
                                   D-meson
    – silicon detectors to identify second decay vertex
    – yield study
            •   109 proton/sec beam
            •   10% target
            •   2×1033 cm-2sec-1
            •   × 1 week = 103 pb-1
            •   acceptance 0.05 – 0.3 to cover forward/mid-
                rapidity/backward
  pT
            D0 yield                               pT > 1.5 GeV/c    5.5×106 D0
                                                                     for 103 pb-1

1.5 GeV/c



       -1                 xF              1   -1                xF                  1
  June 15, 2007                       ECT* Workshop                                     32
         Polarized proton acceleration at J-
                       PARC
          – 50 GeV polarized protons for slow extracted beam
            primary fixed target experiments
          – low intensity (~ 1012 ppp), low emittance (10  mm
            mrad) beams

                                                           pC CNI Polarimeter




                                                                                      Extracted Beam
     -                                                                                Polarimeter
Pol. H Source
                                               Rf Dipole


                     180/400 MeV Polarimeter
                                                                   25-30% Helical Partial Siberian Snakes

                                Thomas Roser (BNL), et al.
     June 15, 2007                       ECT* Workshop                                           33
    Polarized proton acceleration at J-
•
                       PARC
    Intrinsic resonances in RCS

                • emittance: 10 mm-mrad, 95%
                • repetition rate 25Hz
                • sinusoidal ramping
                • kinetic energy: 180MeV – 3GeV




                • intrinsic resonance
                                              =6.18x10-5
                  strength for a particle
                  at an emittance of           Full spin flip by a rf dipole
                  10 mm-mrad

                    Fast tune jump?              =7.63x10-5           =6.60x10-5

                       =2.33x10-5

                                                                  Mei Bai (BNL)
June 15, 2007                          ECT* Workshop                                 34
    Polarized proton acceleration at J-
•
                        PARC
    Spin tracking in 50 GeV MR




                                      average of 12 particles
                                      on an ellipse of 4 mm-
                                      mrad




                                  Alfredo Luccio (BNL)
June 15, 2007     ECT* Workshop                          35
                  Polarized target
• Michigan polarized target
     – existing at KEK
     – target thickness ~3 cm (1%
       target)
     – maybe operational with 1011
       ppp (luminosity ~1034 cm-2s-1)




June 15, 2007             ECT* Workshop   36
                         Physics at 30 GeV
– cross section
     • PYTHIA (6.228) study with PHENIX tune (<kT> = 1.5 GeV/c, Mc =
       1.25 GeV/c2, K-factor = 3.5, Q2 = s)




                                  Wohri and Lourenco


          1 10                                  1 10
                  15                                   15




         0.1    consistent at fixed-target    0.1
                                                    smaller yield (same result
                region, too                         as Laurenco’s study)
     • J-PARC: 3-4 order smaller cross section than that at RHIC
         – can be compensated by higher intensity/luminosity at J-PARC…
June 15, 2007                          ECT* Workshop                             37
                Electron-pair experiment
• E16 experiment at J-
  PARC
     – search for nuclear-
       matter effect in 
       production
     – covering backward
       production of electron-
       positron pairs




June 15, 2007              ECT* Workshop   38
                  SSA measurements
• Neutron
     – large asymmetry found at RHIC
     – production mechanism of neutron
          • one-pion exchange dominant – spin flip




          • figures for study in DIS exps. (HERA), please replace virtual
            photon with proton to apply them for pp reaction
     – asymmetry measurement
          • sensitive to interference between spin-flip term (one-pion
            exchange) and non-spinflip term (other reggeon exchanges)


June 15, 2007                   ECT* Workshop                           39
                    SSA measurements
     – neutron-tagged measurement
          • measure AN of coincident particles at BBC at PHENIX
          • forward neutron, forward BBC, left-right
              – (4.500.500.22)102 < 0
          • forward neutron, backward BBC, left-right
              – (2.280.550.10)102 > 0
     – asymmetry in the forward BBC has the same sign
       while backward particle has opposite sign AN
          Y                     initial-state effect - favored
                 p                   AN(X) < 0, AN(Y) > 0
                p
                    N*(*)  n+X
                         X              final-state effect
                                 p            AN(X) > 0, AN(Y)??
                p            n
June 15, 2007                    ECT* Workshop                     40
                  SSA measurements
     – neutron-tagged measurement of Drell-Yan pair…
          • Jen-Chieh Peng’s calculation expecting sensitivity to the
            meson cloud model, and measurement of pion structure




June 15, 2007                   ECT* Workshop                           41

				
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