plan for a proposal in high-energy hadorn physics at j...
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Plan for a proposal in high-energy hadorn physics at J-PARC
March 12 (Thursday), 2015
pre-workshop meeting
Discussions on J-PARC proposal on high-energy hadron physics
1
Wen-Chen Chang, Takahiro Sawada (Academia Sinica)
Jen-Chieh Peng (UIUC)
Shunzo Kumano, Shinya Sawada (KEK)
Kazuhiro Tanaka (Juntendo)
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 exclusive Drell-Yan process in E50 spectrometer
• Summary & Questions
2
J-PARC High-momentum Beam Line(Hi-P BL)
• High-intensity secondary Pion beam
• High-resolution beam: Δp/p ~ 0.1%
3
Hadron Hall
50GeV Synchrotron
Beam Dump
50GeV Tunnel
Ｔ１ Target(30/50% Loss)
Test BL
Hi-P BL
ExtensionSM1
(2% Loss)T0
0.1% Loss)
Switchyard15kW Loss Target(SM)
30 GeV proton
J-PARC High-momentum Beam Line(Hi-P BL)
• High-intensity secondary Pion beam
• High-resolution beam: Δp/p ~ 0.1%
* Sanford-Wang: 15 kW Loss on Pt, Acceptance :1.5 msr%, 133.2 m
1.0E+03
1.0E+04
1.0E+05
1.0E+06
1.0E+07
1.0E+08
1.0E+09
0 5 10 15 20
Co
un
ts/s
ec
[GeV/c]
1.0E+03
1.0E+04
1.0E+05
1.0E+06
1.0E+07
1.0E+08
1.0E+09
0 5 10 15 20
Co
un
ts/s
ec
[GeV/c]
Negative Hadron Beams(Prod. Angle = 0 deg.)
p-
K-
pbar
p+
K+
Positive Hadron Beams(Prod. Angle = 3.1 deg.)
4
6
http://j-parc-th.kek.jp/html/English/e-index.html
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.
7
Constituent-Counting Rule in Hard Exclusive Process Kawamura et al., PRD 88, 034010 (2013)
8
p n p ++ +0Kpp - + +
2
1( ) ( ) CMn a b c d
da b n nc d f
dt sn n n
-++ + ++
1 3 2 3 7n + + + 2 3 2 3 8n + + +
Physics Processes
• Drell-Yan 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
Quark and Gluon Wigner Phase-Space
Distributions in Protons
10
Wigner Distribution
Transverse Momentum
Dependent PDF
Generalized Parton Distr.
PDF Form Factors
GPD
Ji, PRL91,062001(2003)
( , , )TW r x k
f( , )Tx k
f( )x
F( , , t)x
1 2( ), ( )F t F t
dr
Tdk dx0 & 0x
iq r
Te drdk
2/ 2 , z
qq E t q -
Naïve Assumption:
NMC (Gottfried Sum
Rule):
NA51 (Drell-Yan, 1994):
E866/NuSea (Drell-Yan,
1998):
Light Antiquark Flavor Asymmetry: Drell-Yan Experiments with Proton Beam
11
Tevatro
n 800
GeVMain Injector 120 GeV
𝑑(𝑥)/ 𝑢(𝑥) Measured by
FNAL E906/SeaQuest Experiment
12
Fermilab E906
𝑥𝐵𝑥𝑇 =𝑀
𝑠; smaller s, larger 𝑥𝑇
Unpolarized Drell-Yan using 120
GeV proton beam from Main
Injector
1H, 2H, and nuclear targets
( ( ) / ( )) up to 0.45Td x u x x
13Joint APS/DNP and JPS Meeting , Oct. 7, 2014, Jen-Chieh Peng
50-GeV proton beam
14Joint APS/DNP and JPS Meeting , Oct. 7, 2014, Jen-Chieh Peng
15Joint APS/DNP and JPS Meeting , Oct. 7, 2014, Jen-Chieh Peng
16Joint APS/DNP and JPS Meeting , Oct. 7, 2014, Jen-Chieh Peng
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:
17
1 2
1 2
1 2
( ) 4 ( ) ( )
( ) 4 ( ) ( )
( ) ( ) ( )
p
DY
p
DY
p
DY
p u x u x
n u x d x
p d x d x
p
p
p
p
p
p
-
-
+
-
-
+
1 2 2
21 2
( n) 4 ( )d ( ) ( )
( p) ( )4 ( ) u ( )
p p
DY
ppDY
u x x d x
u xu x x
p
p
p
p
-
-
-
-
1 2 2
21 2
( ) ( ) ( ) ( )
( p) 4 ( )4 ( ) u ( )
p p
DY
ppDY
p d x d x d x
u xu x x
p
p
p
p
+
-
+
-
No nuclear correction for deuteron is needed
Deuterium target
18
Drell-Yan decay angular distributions
Collins-Soper frame
and are the decay polar
and azimuthal angles of the
μ+ in the dilepton rest-frame
0O(
annilation parton model:
) =1, W W= =0; 1, 0T Ls
2 2
2 2 2
(1 cos sin 2 cos sin cos 2 )2
( (1 cos ) (1 cos ) sin 2 cos sin cos 2 )T LW W W W
d
d
+ + +
+ + - + +
1Collinear pQCD
Lam-Tung relation (1978)
: O 2 1 2 =0( ), ; s LW W - -
E615 (PRD 39, 92 (1989)):
Higher Twist Effect at large 𝑥𝜋
19
xp
cos
E615 @ FNAL: Violation of LT RelationPRD 39, 92 (1989)
20
252-GeV p-+W
1 2 =0 - -
cos2 modulation at large Tp
Berger and Brodsky (PRL 42, 940, (1979)) :
Higher Twist Effect at large 𝑥𝜋
2 2
2 2 2
2
4(1 ) (1 cos ) sin
9
Tx kd x
m
p
p
- + +
2(1 cos )d +
21
Brandenburg et al. (PRL 73, 939 (1994)):
Pion Distribution Amplitude
22Pion distribution amplitude: distribution of LC momentum fractions
in the lowest-particle number valence Fock state.
A. P. Bakulev, N. G. Stefanis, and O. V. Teryaev
(Phys. Rev. D 76, 074032 (2007))
Pion Distribution Amplitude
asymptotic-like form = 6y(1-y)
Chernyak-Zhitnitsky (CZ)-like form
Nonlocal QCD sum rules
23
QCD evolution
A. P. Bakulev, N. G. Stefanis, and O. V. Teryaev
(Phys. Rev. D 76, 074032 (2007))
Sensitivity of Pion DA to ,,
*
*
TP
M
0.06 0.3 0.5
24
Dimuon pairs of Large Pt or small M
Theoretical Interpretations of Lam-Tung
Violation in pion-induced DY
25
Boer-Mulders
Function
QCD chromo-
magnetic effect
Glauber gluon
Origin of effect Hadron QCD vacuum Pion specifically
Quark-flavor
dependence
Yes No No
Hadron
dependence
Yes No Yes
Large PT limit 0 Nonzero 0
Reference PRD 60,
014012 (1999)
Z. Phy. C
60,697 (1993)
PLB 726, 262
(2013)
Measurements with different beams , , , and at wide kinematical ranges
would help differentiating the origin.
p K pp
Competing with CERN COMPASS DY Program
Pasquini and Schweitzer (PRD 90, 014050 (2014))
Boer-Mulders Functions of Pion and Proton in
Light-Front Constituent Model
26
E866 (PRL 99 (2007) 082301; PRL 102 (2009) 182001)
Consistency of LT relation for DY events in pd, pp
27
Boer-Mulders functions from
unpolarized pD and pp Drell-YanZ. Lu and I. Schmidt,
PRD 81, 034023 (2010)
V. Barone et al.,
PRD 82, 114025 (2010)
Sign of BM functions and their flavor dependence? 28
u d
u d
u d
Flavor separation of the Boer–Mulders functions
Z. Lu et al. (PLB 639 (2006) 494)
29
2 22
2
cos 2 ( ) cos 2
4 4
T A B TT
A B A B T A B
q d h h llX qW d d q
M M d dx dx d q M M
MIT Bag Model Spectator Model Large Nc limit
Deuterium target
Quark and Gluon Wigner Phase-Space
Distributions in Protons
30
Wigner Distribution
Transverse Momentum
Dependent PDF
Generalized Parton Distr.
PDF Form Factors
GPD
Ji, PRL91,062001(2003)
( , , )TW r x k
f( , )Tx k
f( )x
F( , , t)x
1 2( ), ( )F t F t
dr
Tdk dx0 & 0x
iq r
Te drdk
2/ 2 , z
qq E t q -
x+ x-
t
GPD
s
PP’
( ,0,0) ( ) ( )
( ,0,0) ( ) ( )
f f f
f f f
H x q x q x
H x q x q x
- -
- -
1
1
1
1
2
1
1
1
1
1
( , , ) ( )
( , , ) ( )
( , , ) ( )
( , , ) ( )
f
f
f
f
f A
f
f p
f
dx H x t F t
dx E x t F t
dx H x t g t
dx E x t g t
-
-
-
-
-
-
-
-
)]0,,()0,,([2
1
2
11
1
xExHxdxLJ ff
ff
f ++ -
),,( txGPD
Ji’s sum rule
Generalized Parton Distribution (GPD)
2)'( PPt -
0t
5
( , , ) ( , , )
( , , ) ( , , )
f f
f f
no spin flip H x t H x t
spin flip E x t E x t
0t
31
Spacelike vs. Timelike ProcessesMuller et al., PRD 86 031502(R) (2012)
32
Deeply Virtual Compton Scattering Timelike Compton Scattering
2 0q 2 0q
t<0, space-like GPD
Spacelike vs. Timelike ProcessesMuller et al., PRD 86 031502(R) (2012)
33
Deeply Virtual Meson Production Exclusive Meson-induced DY
2 0q 2 0q
t<0, space-like GPD
𝜋𝑁 → 𝜇+𝜇−𝑁(PLB 523 (2001) 265)
𝑡 = 𝑝 − 𝑝′ 2
𝑄′2 = 𝑞′2 > 0
2 2
2
' '
2 N
Q Q
pq s M
-
( ')
( ')
p p
p p
+
+
-
+ 34
𝜋𝑁 → 𝜇+𝜇−𝑁(PLB 523 (2001) 265)
𝑡 = 𝑝 − 𝑝′ 2
𝑄′2 = 𝑞′2 > 0
2 2
2
' '
2B
N
Q Qx
pq s M
-
( ')
( ') 2
p p
p p
+
+
-
+ - 35
Differential Cross Sections (Q2,t,)E.R. Berger, M. Diehl, B. Pire, PLB 523 (2001) 265
36
𝑡 = 𝑝 − 𝑝′ 2
𝑄′2 = 𝑞′2 > 0
2 2
2
' '
2B
N
Q Qx
pq s M
-
( ')
( ') 2
p p
p p
+
+
-
+ -
Evaluation of Cross Sections
• Input:
– GPD 𝐻(𝑥, 𝜂, 𝑡;Q2), 𝐸(𝑥, 𝜂, 𝑡;Q2)
– Pion distribution amplitude (DA) φ(𝑧;Q2)
• QCD evolutions:
– GPD: Vinnikov framework for LO evolution
– Pion DA: construction by Gegenbauerpolynomials of order 3/2.
• Matrix elements of Exclusive DY.
• Differential cross sections (Q2,t,)
37
GPD 𝐻(𝑥, 𝜂, 𝑡) Double IntegrationE.R. Berger, M. Diehl, B. Pire, EPJC 23, 675 (2002)
38 𝐻(𝑥, 𝜂 = 0, 𝑡 = 0)=polarized valance distribution
GPD 𝐸(𝑥, 𝜂, 𝑡) Pion-pole DominanceE.R. Berger, M. Diehl, B. Pire, EPJC 23, 675 (2002)
39
𝜋𝑁 → 𝜇+𝜇−𝑁E.R. Berger, M. Diehl, B. Pire, PLB 523 (2001) 265
40
𝑸′𝟐 = 𝒒′𝟐 = 𝟓 𝑮𝒆𝑽𝟐
2 2
2
' '0.2
2 N
Q Q
pq s M
-𝑡 = 𝑝 − 𝑝′ 2=-0.2 GeV2
Cross sections increase toward small s!
blue greenred
|t|
GPD 𝐻(𝑥, 𝜂, 𝑡) Double IntegrationS.V. Goloskokov, P.Kroll, EPJC 53, 367 (2008)
41
GPD 𝐻(𝑥, 𝜂, 𝑡) Double IntegrationS.V. Goloskokov, P.Kroll, EPJC 53, 367 (2008)
42
GPD 𝐸(𝑥, 𝜂, 𝑡) Pion-pole DominanceS.V. Goloskokov, P.Kroll, EPJC 53, 367 (2008)
43
Cross Sections of Exclusive DY
2 2
2
' '0.2
2 N
Q Q
pq s M
-
Exclusive DYd
σ/(
dQ
2d
t) (
pb
/GeV
4)
|t| (GeV2)
τ
Cross sections increase toward small s!
dσ
/(d
Q2d
t) (
pb
/GeV
4)
Goloskokov, Kroll
Berger, Diehl, Pire
VinnikovGoloskokov, Kroll
Berger, Diehl, Pire
Vinnikov
J-PARC
GPD dependence
44
A.V. Vinnikov, hep-ph/0604248
Pion Distribution Amplitude (Q2 = 1 GeV2)
45DSE (PRL 111, 092001 (2013))
Pire
Pion Distribution Amplitude
46
QCD evolution
2 3/2 2 (3/2)
2,4,6,...
2 2
( , ) ( )[1 ( ) ( )]
3( , ) ( ) (1 )
4
asym
j j
j
asym
z Q z a Q C z
z Q z z
p p
p p
+
-
(3/2) : Gegenbauer =3/2 polynomialsjC
p DA Asymptotic Chernyak-Zhitnitsky(CZ)
Kroll Dyson-Schwinger equation(DSE)
Q2 (GeV2) infty 1 4 4
a2 0 0.56 0.22 0.20
a4 0 0 0 0.093
a6 0 0 0 0.055
Pion Distribution Amplitude
47
Q2 = 4 GeV2Q2 = 10 GeV2
Q2 = 100 GeV2 Q2 = 10000 GeV2
Pion DA Dependence: Pire GPD
48
The differential cross sections of exclusive DY process shows good sensitivity to pion DA 𝜑𝜋(𝑧).
|t| (GeV2)
Pion DA Dependence: Kroll GPD
49
The differential cross sections of exclusive DY process shows good sensitivity to pion DA 𝜑𝜋(𝑧).
|t| (GeV2)
Pion DA Dependence
50
Kroll
Pire
Pire
Kroll
The discrimination of pion DA and GPD could be done in multi-dimensional distributions.
1.5 GeVM 15 GeVPp
Pp
Hard exclusive production process
51
Constituent-Counting Rule in Hard Exclusive ProcessKawamura et al., PRD 88, 034010 (2013)
52
p n p ++ +0Kpp - + +
2
1( ) ( ) CMn a b c d
da b n nc d f
dt sn n n
-++ + ++
1 3 2 3 7n + + + 2 3 2 3 8n + + +
Quark Degrees of (1405)Kawamura et al., PRD 88, 034010 (2013)
53
0K (1405)pp - + +
1-100 pb
J-PARC
Charm production process
54
WA98: pi(252GeV) N->J/psi +XPRL 58, 2523 (1987)
qqbar anihlation dominating and exclusive production?
56
57
58
59
60
H. Noumi
A neutron target would be useful for the search of some exotic charmed baryons like 𝑑𝑑𝑢𝑢 𝑐 in I=0 channel.
61Stage-1 approved by J-PARC PAC-18, August 12, 2014.
J-PARC E50 Spectrometer + MuID
62
p-
LH2-target
Ring ImageCherenkovCounter
Internal DC
FM magnet
ps-
K+
Fiber tracker
Beam GC
Internal TOF
Internal TOFDC
TOF wall
2m
Decay p(p+)
20 GeV/cBeam p-
Acceptance: ~ 60% for D*, ~80% for decay p+
Resolution: p/p~0.2% at ~5 GeV/c （Rigidity： ~2.1 Tm)
||<60
Scintillator Muon trigger device
+
-
10 GeV/c 20 GeV/c
Beam Intensity High
Total Cross Sectionof Exclusive DY High
High
Acceptance High
π- beam(prod. angle 0 deg)
Total Cross Section of DY
Beam Intensity High
High
Low
Low
Low
Low
Low
Low
of Inclusive DY
15 GeV/cBeam Energy
Yield Estimation
π+ beam(prod. angle 3.1 deg)
63
・ π- beam : 50 days(prod. angle 0 deg)
・ π+ beam : 150 days(prod. angle 3.1 deg)
d/u ratio
GPD
Assumptions:
• Ibeam=107 π/s, Target ; 57cm LH2 , ε(DAQ, Tracking, PID) = 0.9*0.7*0.9, 1 events/day/pb
• Beam momentum resolution: Δp/p = 0.1 %
• Detector resolution: ΔM/M = 1 %
・ Beam Time
・ J-PARC High-p Beam Line
Inclusive DY
Exclusive DY
Yield Estimation
64
Geant 4.9.3(E-50 spectrometer + Muon ID)
・ Exclusive Drell-Yancalculated with GPD by
E.R. Berger, M. Diehl, B. Pire, Eur. Phys. J. C 23, 675 (2002)
・ Inclusive Drell-Yan Pythia 6.4.26
・ BackgroundJAM 1.132
π π+
10 GeV 2.11 nb 0.323 nb
15 GeV 2.71 nb 0.493 nb
20 GeV 3.08 nb 0.616 nb
-
π π+
10 GeV 9.98 pb
15 GeV 7.53 pb
20 GeV 5.83 pb
-
π π+
10 GeV 26.9 mb 24.8 mb
15 GeV 25.8 mb 24.1 mb
20 GeV 25.1 mb 23.5 mb
-
Event GeneratorInclusive Drell-Yan (Mμμ>1.5 GeV)
Exclusive Drell-Yan (Mμμ>1.5 GeV)
Background
Total Cross Section
Particle Transportation + Detector
Yield Estimation
65
π π+
10 GeV 2.11 nb 0.323 nb
15 GeV 2.71 nb 0.493 nb
20 GeV 3.08 nb 0.616 nb
-
π π+
10 GeV 9.98 pb
15 GeV 7.53 pb
20 GeV 5.83 pb
-
π π+
10 GeV 26.9 mb 24.8 mb
15 GeV 25.8 mb 24.1 mb
20 GeV 25.1 mb 23.5 mb
-
Inclusive Drell-Yan (Mμμ>1.5 GeV)
Exclusive Drell-Yan (Mμμ>1.5 GeV)
Background
・ Exclusive Drell-Yancalculated with GPD by
E.R. Berger, M. Diehl, B. Pire, Eur. Phys. J. C 23, 675 (2002)
Geant 4.9.3(E-50 spectrometer + Muon ID)
・ Inclusive Drell-Yan Pythia 6.4.26
・ BackgroundJAM 1.132
Event Generator Total Cross Section
Particle Transportation + Detector
might be several times larger
Yield Estimation
66
𝜋−p → 𝜇+𝜇−𝑛MX In E-50 Spectrometer + MuID
67
1.5 < Mμ+μ- < 2.9 GeV/c2π- beam 50 days
10 GeV 15 GeV 20 GeV
Beam Momentum
Nev
ent
(/0
.01
GeV
/c2)
Missing Mass MX (GeV/c2)
Nev
ent
(/0
.01
GeV
/c2)
Nev
ent
(/0
.01
GeV
/c2)
Missing Mass MX (GeV/c2) Missing Mass MX (GeV/c2)
Exclusive DY
Inclusive DY
Exclusive DY
Inclusive DY
BG BG BG
Exclusive DY
Inclusive DY
• 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 study could be accommodated into the E50 experiment.
S. Sawada (KEK)S. Kumano (KEK)J.C. Peng (UIUC)T. Sawada (AS)W.C. Chang (AS)
GPD(xB,Q2) in both space-like and time-like regime
68
J-PARC’s results in the time-like and large-Q2 region will be complementary to what to be obtained in space-like processes from the deeply virtual Compton scattering (DVCS) deeply virtual meson scattering (DVMS) process to be measured in JLab.
Large-Q2 region
10 GeV 15 GeV 20 GeV
π+ beam 150 days π- beam 50 days
Beam Momentum
(p+/p-) p → μ+ μ- Xd/u measurement with E-50 Spectrometer + MuID
𝑥2
𝑑/𝑢
𝑑/𝑢
𝑑/𝑢
𝑥2 𝑥2
Red lines : CTEQ6.6M
Inclusive DY
Statistics strongly depends on the prod. angle for
secondary beam 69
1.5 < Mμ+μ- < 2.9 GeV/c2
Experimental Difficulties of Detecting 𝜋−𝑝 → 𝐾0Λ(1405)• Multi-particle Acceptance:
• Background?
70
0
0
K (1405)
K
(1405)
pp
p p
p
-
+ -
+ +
+
+
Pion-Induced Exclusive Drell-Yan Process
2small ( )t q q -2large ( )t q q -
: pion distritribution amplitude (DA)p TDA : -N transistion distritribution amplitudep
•DA characterizes the minimal valence Fock state of hadrons.•DA of pion are also explored by pion-photon transition form factor in Belle and Barbar Exps.
•TDA characterizes the next-to-minimal valence Fock state of hadrons.•TDA of pion-nucleon is related to the pion cloud of nucleons.
Bernard Pire , IWHS2011
71
B. Pire, L. Szymanowski, Phys. Lett. B622 (2005) 83
Small cross sections
Exclusive Vector Boson Production
• 𝜋−p → γ∗𝑛
• 𝜋−p → γ∗∆0
• 𝜋−n → γ∗∆−
• 𝜋+n → γ∗p
• 𝜋+p → γ∗∆++
• 𝜋+n → γ∗∆+
• 𝜋−p → 𝐽/𝜓𝑛
• 𝜋−p → 𝐽/𝜓∆0
• 𝜋−n → 𝐽/𝜓∆−
• 𝜋+n → 𝐽/𝜓p
• 𝜋+p → 𝐽/𝜓∆++
• 𝜋+n → 𝐽/𝜓∆+
72
New Physics Search in Drell-Yan like Processes
73
, , , ,...H W Z A
Dark Photon A’
74
p-
LH2-target
Ring ImageCherenkovCounter
Internal DC
FM magnet
ps-
K+
Fiber tracker
Beam GC
Internal TOF
Internal TOFDC
TOF wall
2m
Decay p(p+)
20 GeV/cBeam p-
Acceptance: ~ 60% for D*, ~80% for decay p+
Resolution: p/p~0.2% at ~5 GeV/c （Rigidity： ~2.1 Tm)
||<60
Scintillator Muon trigger device
+
-
'A
Summary (I)
• 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
75
Summary (II)
• Spectrometer with large acceptance and good mass resolution is required for the measurement and such measurement in E-50 conceptual detectors seems promising.
• Availability of deuterium target together with the detection of recoiled protons will enable the measurement of flavor separation of BM functions , valance-quark distributions at large-x and search for some exotic charmed baryons.
• More collaborators are critically necessary!
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Questions
• Will the factorization of exclusive DY process based on a crossing symmetry of DVMP process be a major concern?
• What is the relationship between the inclusive DY process at xF 1 limit and the exclusive one? If these two processes are different, how to differentiate them experimentally, e.g. the missing mass or angular distribution of dimuon pairs?
• What is the relationship between the inclusive J/psi production process at xF 1 limit and the exclusive one?
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