SIDIS Program at 12 GeV Jefferson Lab with SoLID

Tianbo Liu(SoLID Collaboration)

Duke University and Duke Kunshan UniversityThanks Xuefei Yan for inputs with some slides

Radiative Corrections 2016 @ JLab Newport News, VAMay 16-19th 2016

Overview of SoLIDSolenoidal Large Intensity Device

Full exploitation of JLab 12 GeV upgrade The capability to handle high luminosity L ~ 1037-39 cm-2 s-1.

Five highly rated approved experimentsNucleon structure: three-dimensional imaging of the nucleon in momentum space in valence quark region.

E12-10-006, E12-11-007, E12-11-008 (SIDIS)Fundamental symmetries: new physics in the 10~20 TeV region, complementary to the reach of LHC.

E12-10-007 (PVDIS)J/ψ: probe the color field in the nucleon, access to QCD conformal anomaly.

E12-12-006 (J/ψ)

Large acceptance with full 2π azimuthal angle coverage.

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SIDIS @ SoLIDApproved SIDIS experiments 11/8.8 GeV

E12-10-006: Single Spin Asymmetry on Transversely polarized 3He, 90 days.E12-11-007: Single and Double Spin Asymmetry on Longitudinally polarized 3He, 35 days.E12-10-008: Single Spin Asymmetry on Transversely polarized proton (NH3), 120 days.

Pn = 86% , Pp = -2.8%

High statistics (example)

3He bins and 650 proton bins in x, z, Q2, PT

Projected data of E12-10-006

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Run group:E12-10-006A, E12-11-108ADihadron processTarget single spin asymmetry Ay

PVDIS @ SoLIDApproved PVDIS experiment @ 11 GeV

E12-10-007: Parity violating asymmetry in DIS with LH2 and LD2 targets. SoLID projected and

final Qweak results

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J/ψ @ SoLIDApproved J/ψ near threshold production @ 11 GeV

E12-12-006: measure J/ψ near threshold production cross section on proton (LH2).

Run group:E12-12-006A Timelike Compton Scattering (TCS).

Imaginary part: total cross section through the optical theorem.Real part: contains the conformal anomaly.

Probing the strong color field in the nucleon, conformal anomaly (has impact on understanding of the proton mass).

QuarkEnergy33�

QuarkMass11�

GluonEnergy34�

TraceAnomaly22�

Proton mass:

H. Gao et al., The Universe 3, no.2, 18 (2015).5

and µ = 2 GeV

Nucleon Spin DecompositionProton spin puzzle

Quark spin only contributes a small fraction to nucleon spin.

J. Ashman et al.

Spin decomposition

Access to Lq/g

Lattice QCD

It is necessary to have transverse information.Coordinate space: GPDsMomentum space: TMDs

3D imaging of the nucleon.

6

~ 0.3

Unified View of Nucleon Structure

GTMD F(x, ΔT, kT)Generalized Transverse Momentum Dependent

Wigner distribution ρ(x, bT, kT)

TMD f (x, kT)

ΔT = 0

GPD H (x, ξ, t) ΙPD H (x, ξ, bT)

∫d2kT

PDF f (x)

∫d2kT t = 0

∫d2kT

∫dx ∫dx

Form factor F (t) Charge density ρ (bT)

∫dx t = 0 ∫dbT

Charge g

Light-front wave function Ψ (xi, kTi)

5D

3D

1D

7

Unified View of Nucleon Structure

GTMD F(x, ΔT, kT)Generalized Transverse Momentum Dependent

Wigner distribution ρ(x, bT, kT)

TMD f (x, kT)

ΔT = 0

GPD H (x, ξ, t) ΙPD H (x, ξ, bT)

∫d2kT

PDF f (x)

∫d2kT t = 0

∫d2kT

∫dx ∫dx

Form factor F (t) Charge density ρ (bT)

∫dx t = 0 ∫dbT

Charge g

Light-front wave function Ψ (xi, kTi)

5D

3D

1D

h1(x)

δTq

Transversity

Tensor charge8

Structure FunctionsSIDIS differential cross section18 structure functions F(x, z, Q2, PT), model independent. (one photon exchange approximation)

[Diehl&Sapeta EPJC2005]

In parton model, F(x, z, Q2, PT)s are expressed as the convolution of TMDs.

SoLID:4D bins in (x, z, Q2, PT)

9

Leading Twist TMDs

Q Quark Polarization nU L T

U

L

T

_

_

_

_

_

__

f1

g1L

g1T

h1

h1L

h1

h1T

f1T⊥

⊥

⊥

⊥

unpolarized

helicitylongi-transversity

(worm-gear)

trans-helicity(worm-gear)

transversity

pretzelositySivers

Boer-Mulders

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Unpolarized Quark in p↑

Model Calculation

Bacchetta, Conti, Radici

Sivers distributionnaively time-reversal odd.

Measurement in SIDISSingle spin asymmetry(Sivers asymmetry)

FitExp.

6 GeV JLab E06-010, X. Qian et al., PRL 107, 072003 (2011).

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Transverse Spin StructureTransversity

(Collinear & TMD)

A transverse counter part to the longitudinal spin structure: helicity g1L

They are NOT the same due to relativity.Chiral-oddUnique for the quarks.No mixing with gluons.Simpler evolution effect.

NOT accessible via inclusive DIS process.Must couple to another chiral-odd function.(e.g. Collins function H1⊥)Measured via SIDIS (E12-10-006, E12-11-008), Drell-YanDi-hadron (approved as run group with E12-10-006)

6 GeV JLab E06-010, X. Qian et al., PRL 107, 072003 (2011).

Measurement in SIDISSingle spin asymmetry(Collins asymmetry)

Collins fragmentation function

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Soffer’s InequalitySoffer’s bound

Derived by using the positivity constraint onthe forward scattering helicity amplitude.

Global fits of transversity

)2(x

,Q1

x h

ud

x

0

0.1

0.2

0.3

0 0.2 0.4 0.6 0.8 1-0.15

-0.1

-0.05

0

0.05

2 = 2.4 GeV2Q 2 = 10 GeV2Q2 = 1000 GeV2Q

M. Anselmino et al.

Z.-B. Kang et al.

Test Soffer’s inequality @ SoLID13

PretzelosityPretzelosity distribution

6 GeV JLab E06-010, Y. Zhang et al.

Single spin asymmetry

Chiral-odd. NO gluon analogy.Interference of light-front wave functions differing by ΔL = 2.Measuring the difference between helicity and transversity, and hence relativistic effects. (spherically symmetric models)

Relation to OAM (canonical)

(model dependent)

Measurement in SIDIS

A global fit to 175 data fromCOMPASS, HERMES, and JLabfound comparable with null signal hypothesis at 72% C.L..

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Radiative Correction @ 6 GeV

15

Transversity experiment at Hall A: E06-010

bjx0.15 0.2 0.25 0.3 0.35

nora

d/

rad

0.60.70.80.9

11.1

internal RC+

internal RC-

total RC+

total RC-

hz0.46 0.48 0.5 0.52 0.54 0.56 0.58

nora

d/

rad

0.60.70.80.9

11.1

internal RC+

internal RC-

total RC+

total RC-

)2 (GeV2Q1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3

nora

d/

rad

0.60.70.80.9

11.1

internal RC+

internal RC-

total RC+

total RC-

(GeV)tP0.15 0.2 0.25 0.3 0.35

nora

d/

rad

0.60.70.80.9

11.1

internal RC+

internal RC-

total RC+

total RC-

by Xuefei Yan HAPRAD built in MC. I. Akushvich et al., PL B 672, 35 (2009).

Radiative Correction @ SoLID

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Transverse polarized 3He: E12-10-006 (proposal: a simple estimation)

Estimated by Pythia with RADGEN.

RC under Development @ SoLID

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Internal radiative correction (HAPRAD, etc.) built in MCinternal and external RC combinationfull end-to-end MC under development

Cross section model adjustability: for iterative processesreduce model dependence

Capability for bin-by-bin and unfolding

Exclusive tail: there will be data at the same kinematic for model updating

Collaborating with theorists and other groups to develop full procedure

Present Status On TMD ExtractionsSivers Transversity Pretzelosity

Anselmino et al, EPJA39, 89 (2009)

Collins fragmentation

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parametrization by M. Anselmino et al., EPJ A 39, 89 (2009).

Q2 GeV2

Q2 GeV2

SoLID Impact on Sivers

SoLID projection with transversely polarized neutron and proton data.

95% C.L.

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0.0 0.2 0.4 0.6 0.8 1.0�0.07

�0.06

�0.05

�0.04

�0.03

�0.02

�0.01

0.00

x

xf1T��1�u

0.0 0.2 0.4 0.6 0.8 1.00.00

0.02

0.04

0.06

0.08

xxf1T��1�d

0 100 200

u>T<k

-200 -100 0

d>T<k

Anselmino et al. (2009)

SoLID

Q2 GeV2

Q2 GeV2

x = 0.1

x = 0.1

Quark Transverse Momentum in p↑

parametrization by M. Anselmino et al., EPJ A 39, 89 (2009).

SoLID projection with transversely polarized neutron and proton data.

95% C.L.

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0.0 0.2 0.4 0.6 0.8 1.0�0.6

�0.5

�0.4

�0.3

�0.2

�0.1

0.0

k��GeV

x2k � mpf 1T�u

0.0 0.2 0.4 0.6 0.8 1.00.0

0.1

0.2

0.3

0.4

0.5

0.6

k��GeVx2

k � mpf 1T�d

MeV

Transverse momentum:

Q2 GeV2 Q2 GeV2

SoLID Impact on Transversity

parametrization by M. Anselmino et al.

SoLID projection with transversely polarized neutron and proton data.

95% C.L.

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0.0 0.2 0.4 0.6 0.8 1.00.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

x

xh1u �x�

0.0 0.2 0.4 0.6 0.8 1.0

�0.2

�0.1

0.0

0.1

xxh1d �x�

-0.2 0 0.2 0.4

[0,1] uzL

-0.5 0 0.5

[0,1] dzL

Lefky et al. (2015)

SoLID

Q2 GeV2 Q2 GeV2

SoLID Impact on Pretzelosity

parametrization by C. Lefky et al.SoLID projection with transversely polarized neutron and proton data.

95% C.L.

OAM:

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0.0 0.2 0.4 0.6 0.8 1.0�0.2

�0.1

0.0

0.1

0.2

x

xh1T��1�d

0.0 0.2 0.4 0.6 0.8 1.0�0.10

�0.05

0.00

0.05

0.10

x

xh1T��1�u

0 0.5 1

[0,1] uT

-1 -0.5 0

[0,1] dT

Anselmino et al (2013a)

Anselmino et al (2013b)

Radici et al (2015)

Kang et al (2015)

Alexandrou et al (2014)

Bhattacharya et al (2015)

SoLID Projection

Extraction from Experiments:

Lattice QCD:

Tensor ChargeDefinition

A fundamental QCD quantity. Matrix element of local operators.Moment of transversity distribution. Valence quark dominant.Calculable in lattice QCD.

SoLID impact

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Tensor Charge and Neutron EDMTensor charge and EDM

Electric Dipole Moment

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current neutron EDM limit

�0.3 �0.2 �0.1 0.0 0.1 0.2 0.3�3

�2

�1

0

1

2

3

dd�10�25e cm

d u�10�25

ecm

Anselmino et al. with �dn��2.9�10�26e�cmSoLID with �dn��2.9�10�26e �cmSoLID with �dn��2.9�10�28e�cm

SummaryLepton scattering is a powerful tool to probe the internal structure of the nucleon.Unprecedented precision with high luminosity and large acceptance at JLab 12-GeV with SoLID.SoLID-SIDIS program: multi-dimensional mapping in valence quark region with high precision. TMD: transverse imaging of the nucleon, access to orbital angular momentum.Tensor charge and neutron EDM, constraint on new physics.Developing full procedure for RC and physics extraction.

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Thank you!

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Backup

Exclusive tail @ 6 GeV

27

Transversity experiment at Hall A: E06-010

by Xuefei Yan (GeV)tP

0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5

Excl

usiv

e ra

tio

0

0.02

0.04

0.06

0.08

0.1 +

-

)2 (GeV2Q1.5 2 2.5 3

Excl

usiv

e ra

tio

0

0.02

0.04

0.06

0.08

0.1 +

-

bjx0.15 0.2 0.25 0.3 0.35 0.4

Excl

usiv

e ra

tio

0

0.02

0.04

0.06

0.08

0.1 +

-

hz0.46 0.48 0.5 0.52 0.54 0.56 0.58

Excl

usiv

e ra

tio

0

0.02

0.04

0.06

0.08

0.1 +

-

Exclusive model. R. Asaturyan et al., PR C 85, 015202 (2012).

SoLID Impact on Transversity TMD

parametrization by M. Anselmino et al.

SoLID projection with transversely polarized neutron and proton data.

95% C.L.

Q2 GeV2x = 0.1

Q2 GeV2x = 0.1

28

0.0 0.2 0.4 0.6 0.8 1.0

�0.10

�0.05

0.00

0.05

k��GeVxh1d �x,k �

�0.0 0.2 0.4 0.6 0.8 1.0

0.00

0.05

0.10

0.15

k��GeV

xh1u �x,k �

�

What Else in SIDIS @ SoLIDWorm-gears

Trans-helicity (worm-gear).Interference of light-front wave functions differing by ΔL = 1.

Subleading twist effect

Unpolarized process

Measured by DSA

(The other worm-gear from .)

from twist-3 TMDs.Beam spin asymmetry

Other subleading twist asymmetries, e.g.

Multiplicity or differential cross section.

Cahn effect Boer-Mulders effect

29