SoLID Update. Hall A Collaboration Meeting January th Tianbo Liu (SoLID Collaboration) Duke University and Duke Kunshan University

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1 SoLID Update Hall A Collaboration Meeting January th 2017 Tianbo Liu (SoLID Collaboration) Duke University and Duke Kunshan University 1

2 Overview of SoLID Solenoidal Large Intensity Device Full exploitation of JLab 12 GeV upgrade with broad physics Luminosity ~ cm -2 s -1 (open geometry) 3D nucleon structure TMD (Semi-inclusive DIS) GPD (TCS, DVMP, DVCS, DDVCS) Strong color field inside nucleon J/ψ production near threshold Luminosity ~ cm -2 s -1 (baffled geometry) Standard model test, new physics, hadron physics (d/u, CSV, ) Parity-violating DIS Five highly rated approved experiments Three SIDIS, one PVDIS, one J/ψ production Run group: di-hadron, TCS, inclusive SSA Strong collaboration 250+ collaborators from 70+ institutes, 13 countries Significant international collaborations Strong theoretical support 2 Target Collimator GEM Scint SoLID (SIDIS He3) EM Calorimeter (large angle) angl))) Coil and Yoke 1 m SoLID (PVDIS) Target Coil and Yoke 1 m Baffle GEM Light Gas Cherenkov Cherenkov Heavy Gas Cherenkov GEM Scint EM Calorimeter (forward angle) MRPC Beamline EM Calorimeter (forward angle) Beamline

3 Interest in SoLID Physics SoLID Stony Brook Univ. January 28-30, 2016 TMD ECT* April 11-15, 2016 Proton Mass Temple Univ. March 28-29, 2016 BSM and PVDIS ECT* August 1-5, 2016 Hadon Physics Wuhan August 8-11, 2016 Proton Mass ECT* April 3-7, 2017 Hadron/Nuclei INT August 28 - September 29,

4 PVDIS Program Approved PVDIS experiment E : Parity violating asymmetry in DIS with LH2 and LD2 targets. APV = σ R σl σr + σl Sub 1% precision over broad kinematic range High luminosity ~ cm -2 s -1 Large scattering angle large x and y Precision test of SM with sensitivity to new PV physics in 10~20 TeV Search for charge symmetry violation at partonic level Test QCD higher twist corrections Measure d/u ratio for proton free of nuclear effect 4

5 PVDIS Program Test new physics beyond SM SoLID + final Qweak 6 GeV PVDIS [Nature2014] + other experiments SM sin 2 θw measurement Charge symmetry violation d/u ratio free of nuclear effect 5

6 SIDIS Program Approved SIDIS experiments E : Single Spin Asymmetry on Transversely polarized 3 He, 90 days. E : Single and Double Spin Asymmetry on Longitudinally polarized 3 He, 35 days. E : Single Spin Asymmetry on Transversely polarized proton (NH3), 120 days. 4D bins (example) Effective polarized neutron target Two run groups: E A, E A Dihadron process Target single spin asymmetry Leading twist TMDs Projected data of E

7 SIDIS Program: Impact (Transversity) Transversity: Transversely polarized quark density Chiral odd Both collinear and TMD Collins asymmetry in SIDIS Model: KPSY2015 Z.-B. Kang, A. Prokudin, P. Sun, F. Yuan, Phys. Rev. D 93, (2016). Fit Collins asymmetries in SIDIS and e + e - SIDIS data from HERMES, COMPASS and JLab-6 e + e - data from BELLE and BABAR TMD evolution SIDIS process kinematics: xh1(x) Error World / Error SoLID World vs. SoLID including systematics Q 2 =2.4 GeV 2 xh1(x) Error JLab12 / Error SoLID JLab12 vs SoLID u d Q 2 =2.4 GeV x x current fragmentation (TMD factorization) 7 In collaboration with theorists: N. Sato, A. Prokudin, Z.-B. Kang, P. Sun, F. Yuan

8 SIDIS Program: Impact (Tensor Charge) Tensor charge A fundamental QCD quantity: matrix element of local operators. Moment of the transversity distribution: valence quark dominant. Calculable in lattice QCD. SoLID impact With both statistical and systematic errors 1 order of magnitude improvement DSE Lattice Models Global Analysis SoLID Projection truncated full Pitschmann et al (2015) Gockeler et al (2005) Aoki et al (2010) Green et al (2012) Bhattacharya et al (2013) Gupta et al (2014) Bali et al (2015) Bhattacharya et al (2016) He, Ji (1995) Schweitzer et al (2001) Pasquini et al (2007) Wakamatsu (2007) Wakamatsu (2007) Gamberg, Goldstein (2001) Anselmino et al (2013) Goldstein et al (2014) Radici et al (2015) Kang et al (2015) SoLID g T Z. Ye, N. Sato, K. Allada, T. Liu., J.-P. Chen, H. Gao, Z.-B. Kang, A. Prokudin, P. Sun, F. Yuan, arxiv:

9 J/ψ Program Approved J/ψ near threshold production E : measure J/ψ near threshold production cross section on proton (LH2). Run group: E A Timelike Compton Scattering (TCS). Imaginary part: total cross section through the optical theorem. Real part: contains the conformal anomaly. Proton mass: Quark Energy 33 Quark Mass 11 threshold at 8.2 GeV and µ = 2 GeV Trace Anomaly 22 Gluon Energy 34 H. Gao et al., The Universe 3, no.2, 18 (2015). 9 electro- and photo- production with unprecedented precision in unexplored region Probe color force inside the nucleon Conformal anomaly (proton mass budget) A window for future J/ψ-N interaction studies

10 GPD Program Timelike Compton scattering (TCS) from an unpolarized LH2 target - approved as a run-group experiment with the J/ψ experiment E A Double DVCS (DDVCS) in the dilepton channel from an unpolarized LH2 target - has been reviewed by PAC43 as LOI once this experiment has run, a later phase of measurements might include muon pair channel DVCS on a polarized 3 He target - no polarized neutron-dvcs experiment has been proposed at JLab - under study 10 General Compton processes Deeply virtual meson (π ) production from a transversely polarized 3 He target - proposed as a run-group experiment with the transversely polarized 3 He SIDIS experiment as PR B - detailed studies on uncertainties are underway

11 SoLID Progress Simulation Gean4/GEMC with all subsystems combined in the whole SoLID simulation More realistic estimation of acceptance, background, triger rate Tracking One time-sample from APV25 and realistic GEM digitization simulation Track finding framework Magnet Transfer to JLab mostly completed, only the return steel remains ECal and SPD Beam test in Hall A during Fall 2016 run period MRPC Studies to improve the timing resolution from 80 ps (current) to 20 ps GEM Progress in Chinese groups: large area GEM foil, imaging test, LGC A prototype planned to be test in Hall C HGC Conceptual design, a small wooden mock-up of the prototype constructed, window test 11

12 Sub-systems: Magnets Magnets Disassembly complete, transfer to JLab mostly complete, placed in the test Hall Starting field modeling. Will use magnetic forces extracted from the previous study for the next iteration of structural analysis Magnet in the test Hall 12

13 Sub-systems: EC and SPD EC and SPD Cosmic test of GEM+SPD continued at UVa to end of September Test of the radiative preshower goes well. Some preliminary results. Beam test in Hall A 2016, will continue in Hall C

14 Sub-systems: GEM GEM CIAE: progress in GEM foil industrialization, 40cm 40cm, single/double mask LZU: working on online gamma-rejection and clustering USTC: GEM characterization, low-mass design, and APV25 readout with new connectors UVa: recently built two large area (123cm 55cm) GEM detectors, and were successfully used in PRad experiment. New APV25 hybrid being tested with GEM Largest GEM built and ran in experiment 14

15 Tracking Kalman Filter algorithm Prediction: predict state vector at next measurement site Error propagation: propagate the covariant matrix to the next measurement site and calculate the process noise matrix along the way Filtering: the weighted mean of the predicted state vector and the measurement vector on detector are calculated Being developed and tested for SIDIS configuration with the 3 He target One time-sample from APV25 and realistic GEM digitization simulation Single electron track and single pion track Efficiency of the single track finder with background: 86.5% Track fitting resolution Doing and to do Track finding framework also developed for PVDIS and J/ψ configurations, under testing Simulate the response of GEM detectors and related electronics to a more realistic level Study the possibility of track finding on a level-3 farm to reduce the data size 15

16 Kaon Identification TOF time resolution requirement for K/π separation Kaon identification over a momentum range 1 ~ 7 GeV/c Flight distance of 7.7 m 20 ps time resolution is required for 3σ separation between pions and kaons (100 ps time resolution is required for pion identification) Option 1: Large area picosecond photodetector (LAPPD) Use micro channel plate (MCP) photomultipliers 20 ps resolution for a single photoelectron has been achieved Under 10 ps resolution could be obtained for multiple photoelectrons Drawback: high cost of MCP PMT per area Option 2: Improving the timing performance of the MRPC Currently designed MRPC can reach 50 ps with test beam, and 80 ps in high background area A joint Chinese collaboration for SoLID, sphenix, and EIC for the next generation MRPC aims at 20 ps resolution Tsinghua U., USTC, CCNU are planning to develop a prototype in the coming year 16

17 Timeline End of 2016 Response to director s review (finished) Spring 2017 Update precdr to draft MIE Spring-summer 2017 Science review Feb Budget briefing to have SoLID in FY 2020 Start full project Thank you! 17

18 Backup 18

19 PVDIS Program: Baffle Design Materials comparison Optimized geometry DIS electrons (W > 2 GeV, Q 2 > 6 GeV 2, x > 0.55) Photons optimized previous 19

20 J/ψ Program: Bin Migration Simulation studies including approximate radiative effects External bremsstrahlung applied to both incident and scattered electrons Incident electron radiation loss calculated with peaking approximation Scattered electron radiative loss calculated within Geant4/GEMC and folded into total resolution smearing of the track Internal bremsstrahlung calculated with Q 2 dependent equivalent radiator method Simulation of the cross section including acceptance effects Continue developing radiative correction procedure with exact calculations, accurate unfolding, and tests of model dependence no radiative effects include radiative effects 20

21 Nucleon Spin Decomposition Proton spin puzzle Spin decomposition ~ 0.3 Quark spin only contributes a small fraction to nucleon spin. J. Ashman et al., PLB 206, 364 (1988); NP B328, 1 (1989). Lattice QCD (kinetic decomposition) = JAM Collaboration, PR D 93, (2016). Access to Lq/g χqcd Collaboration, PR D 91, (2015). It is necessary to have transverse information. Coordinate space: GPDs Momentum space: TMDs 3D imaging of the nucleon. 21

22 5D Unified View of Nucleon Structure Light-front wave function Ψ (xi, kti) GTMD F(x, ΔT, kt) Generalized Transverse Momentum Dependent Wigner distribution ρ(x, bt, kt) ΔT = 0 d 2 kt d 2 kt 3D TMD f (x, kt) GPD H (x, ξ, t) ΙPD H (x, ξ, bt) d 2 kt t = 0 dx dx 1D PDF f (x) Form factor F (t) Charge density ρ (bt) dx t = 0 dbt Charge g 22

23 SIDIS differential cross section Structure Functions 18 structure functions F(x, z, Q 2, PT), model independent. (one photon exchange approximation) [Diehl&Sapeta EPJC2005] SoLID: 4D bins in (x, z, Q 2, PT) In parton model, F(x, z, Q 2, PT)s are expressed as the convolution of TMDs. 23

24 The goal of the fitting Expectation value: Variance: Using Bayes theorem: Error Estimation Methodology Evaluate E[O] and V[O] Monte Carlo method: Maximum likelihood: Hessian method: 24

25 Impact of SoLID Data: Transversity Evaluate the covariant matrix including SoLID data The improvement on transversity distributions SoLID proton target SoLID neutron target SoLID proton + neutron targets xh1(x) Q 2 =2.4 GeV 2 acceptance Q 2 =2.4GeV 2 KPSY15(u) KPSY15(d) After SoLID 0.8 δh SoLID /δh KPSY u d With both statistical and systematic errors 1 order of magnitude improvement x x x Z. Ye, N. Sato, K. Allada, T.L., J.-P. Chen, H. Gao, Z.-B. Kang, A. Prokudin, P. Sun, F. Yuan, arxiv:

26 Comparison with SBS+CLAS12: Sivers 0.06 World vs. JLab World vs. SoLID 0.06 JLab12 vs. SoLID 0.06 World vs. SoLID including systematics xf?(1) 1T (x, Q 2 ) xf?(1) 1T (x, Q 2 ) xf?(1) 1T (x, Q 2 ) xf?(1) 1T (x, Q 2 ) Q 2 =2.4 GeV Q 2 =2.4 GeV Q 2 =2.4 GeV Q 2 =2.4 GeV 2 Error World / Error JLab u v d v Error World / Error SoLID Error JLab12 / Error SoLID Error World / Error SoLID x x x x 26

27 Systematic Uncertainties PVDIS: Polarimetry (rel.) 0.4% Q 2 (rel.) 0.2% Radiative correction (rel.) 0.2% Reconstruction (rel.) 0.2% Total 0.6% SIDIS: Raw asymmetry (abs.) 1.4E-03 Detector resolution (abs.) <1E-4 Target polarization (rel.) 3% Nuclear effect (rel.) 4~5% Random coincidence (rel.) 0.2% Radiative correction (rel.) 2~3% Diffractive meson (rel.) 3% Total 6~7%+1.4E-3 J/ψ: Acceptance: dominant < 10% sub-detectors, luminosity, target windows background contaminations a couple percents Total ~ 11% 27

28 LGC Plan to test in Hall C for a prototype Sub-systems: LGC Mounting for 3 3 tiling 28

29 Sub-systems: HGC HGC Conceptual design (Duke) and a small wooden mock-up of the prototype constructed (Regina) Entrance window pressure test LHCb-type mirror samples for aluminization test and reflective coating Choices of readout board: CLAS12 RICH MAROC3 with additional a total sum (waiting for design) or summing board designed by the detector group Plan to test in Hall C for a prototype conceptual design window test summing board 29

30 Comparison with SBS+CLAS12 Transversity: 0.4 World vs. JLab World vs. SoLID 0.4 JLab12 vs SoLID xh1(x) 0.0 xh1(x) 0.0 xh1(x) Q 2 =2.4 GeV Q 2 =2.4 GeV Q 2 =2.4 GeV 2 Error World / Error JLab Error World / Error SoLID u d Error JLab12 / Error SoLID Tensor charge: x x x 30