1. (Proposal of) High-energy hadron experiments at J-PARC
KEK theory center workshop on
Hadron physics with high-momentum hadron beams at J-PARC in 2015
March 13-16, 2015, KEK, Tsukuba, Japan
(Proposal of) High-energy hadron experiments at J-PARC
Wen-Chen Chang
Institute of Physics, Academia Sinica
in collaboration with
Takahiro Sawada (Academia Sinica)
Jen-Chieh Peng (UIUC)
Shunzo Kumano, Shinya Sawada (KEK)
Kazuhiro Tanaka (Juntendo)

2. Outline Uniqueness of hadron physics studied at HiPBL of J- PARC
Physics processes under consideration:
Drell-Yan process
Hard exclusive process
Charm production process
Feasibility study of measuring the exclusive Drell- Yan process in E50 spectrometer.
Summary & Final remarks

3. J-PARC High-momentum Beam Line
(Hi-P BL)
High-intensity secondary Pion beam
High-resolution beam: Δp/p ~ 0.1%
Ｔ１ Target
(30/50% Loss)
50GeV Synchrotron
Extension
SM1
(2% Loss) T0
0.1% Loss)
50GeV Tunnel
Test BL
30 GeV proton
Hi-P BL
Switchyard
15kW Loss Target
(SM)
Hadron Hall
Beam Dump

4. J-PARC High-momentum Beam Line
(Hi-P BL)
High-intensity secondary Pion beam
High-resolution beam: Δp/p ~ 0.1%
Negative Hadron Beams
(Prod. Angle = 0 deg.)
Positive Hadron Beams
(Prod. Angle = 3.1 deg.) p- p+ K- K+
pbar
* Sanford-Wang: 15 kW Loss on Pt, Acceptance :1.5 msr%, m

6. Thanks to Shunzo Kumano and many colleagues!
Thanks to Shunzo Kumano and many colleagues!

7. Uniqueness of hadron physics studied at HiPBL of J-PARC
The beam energy of hadrons at J-PARC at 5-15 GeV ( 𝑠 =𝟑−𝟓.𝟓 GeV) might be most ideal for studying the hard exclusive processes and discerning the quark-hadron transition in the strong interaction.
Valance-like partonic degrees of freedom of hadrons could be discerned, compared to the collisions at low- energy regime.
Reasonably large cross sections, compared to those at higher energies.

8. Physics Processes Drell-Yan process Hard exclusive production process
Inclusive pion-induced Drell-Yan:
u/d(x) at large x
Violation of Lam-Tung relation, BM functions
Pion PDF and DA
Exclusive pion-induced Drell-Yan
GPD and TDA of proton
Pion DA
Hard exclusive production process
Exclusive pion-N Lambda(1405) production
Valence quark structure of Lambda(1405)
Charm production process
Inclusive pion-N J/psi production: J/psi production mechanism
Exclusive pion-N J/psi production: Intrinsic charm?
Exotic charmed baryons

9. Drell-Yan process

10. Quark and Gluon Wigner Phase-Space Distributions in Protons
Wigner Distribution
Ji, PRL91,062001(2003)
GPD
Transverse Momentum Dependent PDF
Generalized Parton Distr.
Then, the function Wn(x, p) corresponds to the classical　trajectory in the phase space given by the coordinates x
and p. Therefore, the delocalization of the Wigner distribution　indicates quantum effects due to the uncertainty
principle. The Wigner distribution provides information　on quantum states by using the phase-space concept.
PDF
Form Factors

11. Light Antiquark Flavor Asymmetry: Drell-Yan Experiments with Proton Beam
Naïve Assumption:
NMC (Gottfried Sum Rule):
NA51 (Drell-Yan, 1994):
E866/NuSea (Drell-Yan, 1998):
Drell-Yan process where quark and antiquark from colliding hadrons annihlnate into virtual photon and then decaying into di-lepton offer the chance of looking the x-dependence of ubar and dbar difference beyond the x-integrated value.
NA51 is the first one, confirming dbar>ubar at x=0.18

12. Constraint of x( 𝑑 − 𝑢 ) in Global Analysis
E. Pereza and E. Rizvib, arXiv:

13. Parton distributions: MMHT 2014 PDFs
L. A. Harland-Lang, A. D. Martin, P. Motylinski, R.S. Thorne, arXiv:

14. Origin of 𝑢 (𝑥)≠ 𝑑 (𝑥): Perturbative QCD effect?𝑞
Pauli blocking
𝑔→𝑢 𝑢 is more suppressed than 𝑔→𝑑 𝑑 in the proton since |p>=|uud> (Field and Feynman 1977)
pQCD calculation (Ross, Sachrajda 1979)
Bag model calculation (Signal, Thomas, Schreiber 1991)
Chiral quark-soliton model (Pobylitsa et al. 1999)
Instanton model (Dorokhov, Kochelev 1993)
Statistical model (Bourrely et al. 1995; Bhalerao 1996)
Balance model (Zhang, Ma 2001)
pQCD is less than 1% effect.
The valance-quark configuration affects the gluon splitting.

15. Origin of 𝑢 (𝑥)≠ 𝑑 (𝑥): Non-perturbative QCD effect?
Meson cloud in the nucleons (Thomas 1983, Kumano 1991): Sullivan process in DIS.
Chiral quark model (Eichten et al. 1992; Wakamatsu 1992): Goldstone bosons couple to valence quarks. n
Pion cloud is a source of antiquarks in the protons and it lead to 𝑑 > 𝑢 .

16. Short-Range Structure of Hadron
Extrinsic Sea
Intrinsic Sea
Gluon splitting
Gluon fusion & light quark scattering
Perturbative radiation
Spatial overlapping of partons
CP invariant
Possible CP non-invariant
Fast fluctuation
With a longer lifetime
Of small x
Of large x (valence-like)
Strong Q2 dependent
Small Q2 dependent
For further understanding of sea quarks, it might be helpful to classify them into two types depending on their origin.
Hoyer and Brodsky, AIP Conf. Proc. 221, 238 (1990)

17. Intrinsic Sea Quarks in Light-Front 5q Fock States
“extrinsic”
Brodsky, Hoyer, Peterson, Sakai (BHPS) PLB 93,451 (1980); PRD 23, 2745 (1981)
Dominant Fock state configurations have the minimal invariant mass, i.e. the ones with equal-rapidity constituents.
The large charm mass gives the c quark a larger x than the other comoving light partons, more valence-like.
The existence of IC will lead to large contribution to charm production at large x.

18. Data of 𝑑 𝑥 − 𝑢 𝑥 vs. Light-Front 5q Fock States
The data are in good agreement with the 5q model after evolution from the initial scale μ to Q2=54 GeV2
The difference of these two 5-quark components could be determined.
Assuming there existing a difference of probability intrinsic uudddbar state and uuduubar, we construct the x distribution from light-front 5q model in a numerical way at certain initial scale. Then we evolve the x distribution to the experimental scale at Q2=54 GeV2. The difference of these two 5-quark components could be determined.
W.C. Chang and J.C. Peng, PRL 106, (2011)
Jen-Chieh Peng (March 14)

19. 𝑑 𝑥 − 𝑢 𝑥 vs. Theoretical Models
𝑢 > 𝑑 ?

20. Momentum Dependence of the Flavor Structure of the Nucleon Sea: NMC vs E866 J.C. Peng, W.C. Chang, H.Y. Cheng, T.J. Hou, K.F. Liu, and J.W. Qiu PLB 736 (2014) 411
NMC/JR14
JR14
NMC

21. Diagrams of QCD quantum fluctuation 𝑢 > 𝑑 J.C. Peng, W.C. Chang, H.Y. Cheng, T.J. Hou, K.F. Liu, and J.W. Qiu PLB 736 (2014) 411 1 1 2 4 3
1. Gluon radiation
2. Gluon splitting
3. 𝑞 𝑞 recombination
4. Gluon absorption

22. 𝑑 (𝑥)/ 𝑢 (𝑥) Measured by FNAL E906/SeaQuest Experiment
Fermilab E906
𝑥 𝐵 𝑥 𝑇 = 𝑀 𝑠 ; smaller s, larger 𝑥 𝑇
Unpolarized Drell-Yan using 120 GeV proton beam from Main Injector
1H, 2H, and nuclear targets
Fixed Target Beam lines
Tevatron 800 GeV
Main Injector 120 GeV
Paul Reimer (March 14)

23. 50-GeV proton beam
Joint APS/DNP and JPS Meeting , Oct. 7, 2014, Jen-Chieh Peng

24. Joint APS/DNP and JPS Meeting , Oct. 7, 2014, Jen-Chieh Peng

25. JLAB 12 GeV, electron beam DIS
Joint APS/DNP and JPS Meeting , Oct. 7, 2014, Jen-Chieh Peng

26. Ratios of d/u(x) at large x by pion-induced Drell-Yan processes
At large x1 and x2:
With deuterium target and spectator tagging:
With both 𝜋 + and 𝜋 − beams:
Deuterium target
No nuclear correction for deuteron is needed

27. Drell-Yan decay angular distributions
 and  are the decay polar and azimuthal angles of the μ+ in the dilepton rest-frame
Collins-Soper frame

28. E615 @ FNAL: Violation of LT Relation PRD 39, 92 (1989)
252-GeV +W

29. Theoretical Interpretations of Lam-Tung Violation in pion-induced DY
TMD Boer-Mulders Function
QCD chromo-magnetic effect
Glauber gluon
Origin of effect
Hadron
QCD vacuum
Pion specifically
Quark-flavor dependence
Yes No
dependence
Large PT limit
Nonzero
Reference
PRD 60, (1999)
Z. Phy. C 60,697 (1993)
PLB 726, 262 (2013)
Competing with CERN COMPASS DY Program

30. Flavor separation of the Boer–Mulders functions Z. Lu et al
Flavor separation of the Boer–Mulders functions Z. Lu et al. (PLB 639 (2006) 494)
MIT Bag Model
Spectator Model
Large Nc limit
Deuterium target

31. E615 (PRD 39, 92 (1989)): Higher Twist Effect at large 𝑥 𝜋
Transversely polarized +1 -1
Longitudinally polarized

32. Berger and Brodsky (PRL 42, 940, (1979)) : Higher Twist Effect at large 𝑥 𝜋

33. Brandenburg et al. (PRL 73, 939 (1994)): Pion Distribution Amplitude
Pion distribution amplitude: distribution of LC momentum fractions
in the lowest-particle number valence Fock state.

34. A. P. Bakulev, N. G. Stefanis, and O. V. Teryaev (Phys. Rev
A. P. Bakulev, N. G. Stefanis, and O. V. Teryaev (Phys. Rev. D 76, (2007)) Pion Distribution Amplitude
QCD evolution
asymptotic-like form = 6y(1-y)
Chernyak-Zhitnitsky (CZ)-like form
Nonlocal QCD sum rules
Oleg Teryaev (March 13)

35. A. P. Bakulev, N. G. Stefanis, and O. V. Teryaev (Phys. Rev
A. P. Bakulev, N. G. Stefanis, and O. V. Teryaev (Phys. Rev. D 76, (2007)) Sensitivity of Pion DA to ,,
Oleg Teryaev (March 13)

36. Generalized Parton Distribution (GPD)
x+x
x-x t
GPDs P P’
Ji’s sum rule

37. Spacelike vs. Timelike Processes Muller et al
Spacelike vs. Timelike Processes Muller et al., PRD (R) (2012)
Deeply Virtual Compton Scattering
Timelike Compton Scattering
Charles Hyde, Katharina Schimdt
(March 14)

38. Spacelike vs. Timelike Processes Muller et al
Spacelike vs. Timelike Processes Muller et al., PRD (R) (2012)
Deeply Virtual Meson Production
Exclusive Meson-induced DY
Charles Hyde, Katharina Schimdt
(March 14)

39. 𝜋𝑁→ 𝜇 + 𝜇 − 𝑁 E.R. Berger, M. Diehl, B. Pire, PLB 523 (2001) 265
Longitudinally polarized
𝑡= 𝑝− 𝑝 ′ 2
𝑄′ 2 = 𝑞′ 2 >0
Kazuhiro Tanaka, Peter Kroll (March 13), Stefan Kofler (March 15)

40. Differential Cross Sections (Q2,t,) E. R. Berger, M. Diehl, B
Differential Cross Sections (Q2,t,) E.R. Berger, M. Diehl, B. Pire, PLB 523 (2001) 265
𝑡= 𝑝− 𝑝 ′ 2
𝑄′ 2 = 𝑞′ 2 >0
Kazuhiro Tanaka, Peter Kroll (March 13), Stefan Kofler (March 15)

41. GPD 𝐻 (𝑥,𝜂,𝑡) Double Integration E. R. Berger, M. Diehl, B
GPD 𝐻 (𝑥,𝜂,𝑡) Double Integration E.R. Berger, M. Diehl, B. Pire, EPJC 23, 675 (2002)
Kazuhiro Tanaka, Peter Kroll (March 13)
𝐻 (𝑥,𝜂=0,𝑡=0)=polarized valance distribution

42. GPD 𝐸 (𝑥,𝜂,𝑡) Pion-pole Dominance E. R. Berger, M. Diehl, B
GPD 𝐸 (𝑥,𝜂,𝑡) Pion-pole Dominance E.R. Berger, M. Diehl, B. Pire, EPJC 23, 675 (2002)
Kazuhiro Tanaka, Peter Kroll (March 13)

43. 𝜋𝑁→ 𝜇 + 𝜇 − 𝑁 E.R. Berger, M. Diehl, B. Pire, PLB 523 (2001) 265
𝑸′ 𝟐 = 𝒒′ 𝟐 =𝟓 𝑮𝒆𝑽 𝟐
Cross sections increase toward small s!
𝑡= 𝑝− 𝑝 ′ 2 =-0.2 GeV2
|t|
blue
red
green
Kazuhiro Tanaka, Peter Kroll (March 13)

44. Pion Distribution Amplitude (Q2 = 1 GeV2)
Pire
DSE (PRL 111, (2013))

45. Pion DA Dependence |t| (GeV2)
The differential cross sections of exclusive DY process shows good sensitivity to pion DA 𝜑 𝜋 (𝑧).

46. Hard exclusive production process

47. Constituent-Counting Rule in Hard Exclusive Process Kawamura et al
Constituent-Counting Rule in Hard Exclusive Process Kawamura et al., PRD 88, (2013)

48. Quark Degrees of (1405) Kawamura et al., PRD 88, 034010 (2013)
1-100 pb
J-PARC
Takayasu Sekihara (March 15)

49. Charm production process

50. WA98: pi(252GeV) N->J/psi +X PRL 58, 2523 (1987)
Is 𝑞 𝑞 annihilation and exclusive production dominating for J/psi at large xF ?
Longitudinally polarized

51. Zein-Eddine Meziani (March 15)

52. Zein-Eddine Meziani (March 15)

53. 𝜋𝑁→𝐽/𝜓𝑋 Near Threshold
Leading Hadron Production from Intrinsic Charm
PLB 81 (1979) 401
Charm quarks at high x -- allows charm states to be produced with minimal energy
(JPRAC π𝑁 𝑠 =𝟑−𝟓.𝟓 GeV)
S. Brodsky, J-PARC workshop, 2013

54. Hiroyuki Noumi, Atsushi Hosaka (March 15)
A neutron target would be useful for the search of some exotic charmed baryons like 𝑑𝑑𝑢𝑢 𝑐 in I=0 channel.

55. Hiroyuki Noumi (March 15)
Stage-1 approved by J-PARC PAC-18, August 12, 2014.

56. J-PARC E50 Spectrometer + MuID
Ring Image
Cherenkov
Counter
Internal TOF
FM magnet
Decay p(p+)
Internal DC K+
LH2-target
20 GeV/c
Beam p-
Beam GC p-
Fiber tracker
||<60
TOF wall DC
Scintillator Muon trigger device
ps-
Internal TOF
Acceptance: ~ 60% for D*, ~80% for decay p+
Resolution: Dp/p~0.2% at ~5 GeV/c　（Rigidity： ~2.1 Tm)

57. 𝜋 − p→ 𝜇 + 𝜇 − 𝑛 MX In E-50 Spectrometer + MuID
π- beam 50 days
1.5 < Mμ+μ- < 2.9 GeV/c2
Beam Momentum
10 GeV
15 GeV
20 GeV
Exclusive DY
Exclusive DY
Nevent (/0.01 GeV/c2)
Nevent (/0.01 GeV/c2)
Nevent (/0.01 GeV/c2)
Inclusive DY
Inclusive DY
Inclusive DY
Exclusive DY BG BG BG
Missing Mass MX (GeV/c2)
Missing Mass MX (GeV/c2)
Missing Mass MX (GeV/c2)
S. Sawada (KEK)
S. Kumano (KEK)
J.C. Peng (UIUC)
T. Sawada (AS)
W.C. Chang (AS)
The signal of exclusive Drell-Yan processes can be clearly identified in the missing mass spectrum of dimuon pairs.
Because of the low event rate, this program could be accommodated into the E50 experiment.

58. GPD(xB,Q2) in both space-like and time-like regime
Charles Hyde, Katharina Schimdt
(March 14)
Large-Q2 region
J-PARC: time-like approach and large-Q2 region.

59. (+/-) p → μ+ μ- X d/u measurement with E-50 Spectrometer + MuID
Inclusive DY
(+/-) p → μ+ μ- X d/u measurement with E-50 Spectrometer + MuID
π+ beam 150 days
π- beam 50 days
1.5 < Mμ+μ- < 2.9 GeV/c2
Beam Momentum
10 GeV
15 GeV
20 GeV
𝑑/𝑢
𝑑/𝑢
𝑑/𝑢
𝑥 2
𝑥 2
𝑥 2
Statistics strongly depends on the prod. angle for secondary beam
Red lines : CTEQ6.6M

60. Exclusive Vector Boson Production

61. Summary
High-energy hadron beam at J-PARC is ideal for studying hard exclusive processes.
The study of 𝜋-induced DY/charm production and hard exclusive processes will offer important understanding on
Nucleon structure: valence quarks PDF; TMD (BM), GPD (TDA)
𝜋 structure: DA and PDF
Structure of exotic hadrons
𝑱/𝝍 production mechanism, exotic charmed baryons
Spectrometer with large acceptance and good mass resolution is required for the measurement. The preliminary feasibility study of measuring the exclusive Drell-Yan process in E-50 spectrometers seems promising.

62. Final Remarks
Many interesting physics ideas are left out, e.g. the studies using nuclear targets and polarized beam/target. We will collect the ideas from the presentations and conversations during this workshop to make a strong/coherent J-PARC proposal.
Collaboration in carrying out the experiments is extremely welcome!

63. Backup

64. Pasquini and Schweitzer (PRD 90, (2014)) Boer-Mulders Functions of Pion and Proton in Light-Front Constituent Model
In a recent work Pasgwini and shivitzer constructs BM function of valance quarks of pion and proton by LF constituent model and the
Nu parameters as a function of pt and x1 in NA10 and E615 can be nicely described.

65. E866 (PRL 99 (2007) ; PRL 102 (2009) ) Consistency of LT relation for DY events in pd, pp

66. Boer-Mulders functions from unpolarized pD and pp Drell-Yan
Z. Lu and I. Schmidt,
PRD 81, (2010)
V. Barone et al.,
PRD 82, (2010)
Sign of BM functions and their flavor dependence?

67. GPD 𝐻 (𝑥,𝜂,𝑡) Double Integration S. V. Goloskokov, P
GPD 𝐻 (𝑥,𝜂,𝑡) Double Integration S.V. Goloskokov, P.Kroll, EPJC 53, 367 (2008)

68. GPD 𝐻 (𝑥,𝜂,𝑡) Double Integration S. V. Goloskokov, P
GPD 𝐻 (𝑥,𝜂,𝑡) Double Integration S.V. Goloskokov, P.Kroll, EPJC 53, 367 (2008)

69. GPD 𝐸 (𝑥,𝜂,𝑡) Pion-pole Dominance S. V. Goloskokov, P
GPD 𝐸 (𝑥,𝜂,𝑡) Pion-pole Dominance S.V. Goloskokov, P.Kroll, EPJC 53, 367 (2008)

70. Differential Cross sections from three GPDs
Kroll
Vinnikov
Pire

71. Differential Cross sections from three GPDs with the same 𝜑 𝜋 (𝑧)
Vinnikov
Kroll
Pire
Pion DA 𝜑 𝜋 (𝑧) affects the exclusive DY cross sections significantly.

72. Pion Distribution Amplitude (Q2 = 1 GeV2)
Pire
DSE (PRL 111, (2013))

73. Pion Distribution Amplitude
 DA
Asymptotic
Chernyak-Zhitnitsky
(CZ)
Kroll
Dyson-Schwinger equation
(DSE)
Q2 (GeV2)
infty 1 4 a2
0.56
0.22
0.20 a4
0.093 a6
0.055
QCD evolution

74. Pion Distribution Amplitude
Q2 = 4 GeV2
Q2 = 10 GeV2
Q2 = 100 GeV2
Q2 = GeV2

75. Pion DA Dependence: Pire GPD
The differential cross sections of exclusive DY process shows good sensitivity to pion DA 𝜑 𝜋 (𝑧).

76. Pion DA Dependence: Vinnikov GPD
The differential cross sections of exclusive DY process shows good sensitivity to pion DA 𝜑 𝜋 (𝑧).

77. Pion DA Dependence: Kroll GPD
The differential cross sections of exclusive DY process shows good sensitivity to pion DA 𝜑 𝜋 (𝑧).

78. Pion DA Dependence
Kroll
Kroll
Pire
Pire
The discrimination of pion DA could be separated from that of GPDs.

79. Differential Cross sections from three GPDs with the same 𝜑 𝜋 (𝑧)
Vinnikov
Kroll
Pire

80. Effects of QCD evolution: Differential Cross sections (Kroll GPD and DSE pion DA)
Black:
GPD_QCD=0
pionDA_QCD=0
QCD evolution effect on GPD is negligible.
Green:
GPD_QCD=1
pionDA_QCD=0
QCD evolution effect on pion DA is minor and depends on the parameterization.
Blue:
GPD_QCD=0
pionDA_QCD=1
Red:
GPD_QCD=1
pionDA_QCD=1

82. Parton Interpretation of GPDs (Phys
Parton Interpretation of GPDs (Phys. Rept, 388, 41 (2003), hep-ph/ ; arXiv: )
GPD
GPD
GPD
DGLAP-II: -1<x<-
PDFs of antiquarks
ERBL: |x|<
DAs of mesons
DGLAP-I: <x<1
PDFs of quarks