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MEIC: A Medium Energy Electron Ion Collider at Jefferson Lab

MEIC: A Medium Energy Electron Ion Collider at Jefferson Lab. R. D. McKeown Jefferson Lab College of William and Mary. QCD and Hadron Physics, Lanzhou March 30, 2013. Outline. Introduction to Jefferson Lab Motivation for Electron Ion Collider - Science goals

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MEIC: A Medium Energy Electron Ion Collider at Jefferson Lab

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  1. MEIC: A Medium Energy Electron Ion Collider at Jefferson Lab R. D. McKeown Jefferson Lab College of William and Mary QCD and Hadron Physics, Lanzhou March 30, 2013

  2. Outline • Introduction to Jefferson Lab • Motivation for Electron Ion Collider -Science goals - Requirements and specifications • MEIC design

  3. Jlab: A Laboratory for Nuclear Science Nuclear Structure Hadrons from Quarks Fundamental Forces & Symmetries Accelerator S&T Medical Imaging Structure of Hadrons Theory and Computation Quark Confinement

  4. Current Jefferson Lab Accelerator Complex Cryomodules in the accelerator tunnel Superconducting radiofrequency (SRF) cavities Hall D (new construction) A C CEBAF Large Acceptance Spectrometer (CLAS) in Hall B B Free Electron Laser (FEL)

  5. 12 GeV Upgrade Project New Hall Add 5 cryomodules 20 cryomodules Add arc 20 cryomodules Add 5 cryomodules Enhanced capabilities in existing Halls Upgrade is designed to build on existing facility: vast majority of accelerator and experimental equipment have continued use Upgrade arc magnets and supplies Maintain capability to deliver lower pass beam energies: 2.2, 4.4, 6.6…. CHL upgrade The completion of the 12 GeV Upgrade of CEBAF was ranked the highest priority in the 2007 NSAC Long Range Plan. • Scope of the project includes: • Doubling the accelerator beam energy • New experimental Hall and beamline • Upgrades to existing Experimental Halls

  6. 12 GeV Scientific Capabilities Hall D – exploring origin ofconfinementby studying exotic mesons Hall B – understanding nucleon structure viageneralized parton distributions Hall C – precision determination of valence quark properties in nucleons and nuclei Hall A–form factors, future new experiments (e.g., SoLIDand MOLLER)

  7. 12 GeV Upgrade Project Schedule FY12: reduction of $16M FY13: Pres Request – no restoration Rebaseline in progress • Present expectation (subject to rebaseline review): • 12 16-month installation • May 2012 - MaySept 2013 • Hall A commissioning start Oct 2013Feb 2014 • Hall D commissioning start • April 2014Oct 2014 • Halls B & C commissioning start Oct 2014Oct 2015 • Project Completion Dec 2016 Next DOE Project Review May, 2013

  8. 12 GeV Project Status Hall D & Counting House Hall D Interior Hall D Drift Chamber Hall C Dipole Magnet Coil SC Magnet Conductor Press • Installation in all 4 Halls has begun • Challenges with superconducting magnets for experiments • All 7 magnets under contract • Schedule delay a concern for two contracts • Hall D solenoid cool-down is underway • Upgrade Project 73% Complete, 85% Obligated • Accelerator commissioning begins October 2013 • Beam to Hall A in 2nd Quarter of FY14 • Beam to Hall D in 1st Quarter of FY15

  9. Beyond 12 GeV Upgrade • Super BigBite Spectrometer • (Approved for FY13-16 construction) • - high Q2 form factors • - SIDIS • MOLLER experiment • (MIE – FY15-18?) • - Standard Model Test • SoLID • Chinese collaboration • CLEO Solenoid • Enhancements of equipment in B, C, D • (Leverage external investments)

  10. JLab12:21st Century Science Questions • What is the role of gluonic excitations in the spectroscopy of light mesons? Can these excitations elucidate the origin of quark confinement? • Where is the missing spin in the nucleon? Is there a significant contribution from valence quark orbital angular momentum? • Can we reveal a novel landscape of nucleon substructure through measurements of new multidimensional distribution functions? • What is the relation between short-range N-N correlations, the partonic structure of nuclei, and the origin of the nuclear force? • Can we discover evidence for physics beyond the standard model of particle physics?

  11. 12 GeVApproved Experiments by PAC Days More than 7 years of approved experiments

  12. 12 GeV White Paper 1Executive Summary 2Meson Spectroscopy, Hybrid Mesons & Confinement 3The Internal Structure of Hadrons 4QCD and Nuclei 5The Standard Model and Beyond 6Appendix A: Experimental Equipment arXiv:1208.1244

  13. Electron Ion Collider NSAC 2007 Long-Range Plan: “An Electron-Ion Collider (EIC)with polarized beams has been embraced by the U.S. nuclear science community as embodying the vision for reaching the next QCD frontier. EIC would provide unique capabilities for the study of QCD well beyond those available at existing facilities worldwide and complementary to those planned for the next generation of accelerators in Europe and Asia.” • Jefferson Lab and BNL developing facility designs • Joint community efforts to develop science case  white paper (2013)

  14. 2010 NRC Decadal Study

  15. Recent Documents

  16. The Landscape of EIC • An EIC aims to study gluon dominated matter. • With 12 GeV we study mostly the valence quark component mEIC EIC 12 GeV

  17. EIC Science (I) EIC will complete our knowledge of the nucleon through exploration of the gluon-dominated regime at low x. • How much spin is carried by gluons? • Does orbital motion of sea quarks contribute to spin? - Generalized parton distributions (GPD) - Transverse momentum dependent (TMD) distributions • What do the parton distributions reveal in transverse momentum and coordinate space?

  18. EIC Science (II) Map the gluon field in nuclei • What is the distribution of glue in nuclei? • Are there modifications as for quarks? • Can we observe gluon saturation effects? Study spacetime evolution of color charges in nuclei • How do color charges evolve in space and time? • How do partons propagate in nuclear matter? • Can nuclei help reveal the dynamics of fragmentation? Search for physics beyond the standard model

  19. EIC Requirements From the 2013 EIC White Paper:

  20. The Reach of EIC • High Luminosity •  1034cm-2s-1 • Low x regime • x  0.0001 • High Polarization •  70% JLab 12 EIC Discovery Potential! EMC/E665 HERMES

  21. Polarized Luminosity (x,Q2) phase space directly correlated with s (=4EeEp) : @ Q2 = 1 lowest x scales like s-1 @ Q2 = 10 lowest x scales as 10s-1 x = Q2/ys current data w/ EIC data

  22. Polarized Luminosity: SIDIS Major improvement over present data!

  23. Medium Energy EIC@JLab SRF linac Pre-booster Warm large booster (up to 20 GeV) Transfer beam line Ion source Cold ion collider ring (up to 100 GeV) Electron collider ring (3 to 12 GeV) Medium energy IP Injector • JLab Concept • MEIC: • 3-12 GeV on 20-100 GeVep/eA collider • fully-polarized, longitudinal and transverse • luminosity: up to few x 1034 e-nucleons cm-2 s-1 • Upgradable to higher energies (250 GeV protons) 12 GeV CEBAF

  24. MEIC Design Report • Posted: arXiv:1209.0757 • Stable concept for 3 years “world’s first polarized e-p collider and world’s first e-A collider” • Overall MEIC design features: • Highly polarized (including D) • Full acceptance & high luminosity • Minimize technical risk and R&D • EPJA article by JLab theory on MEIC science case • (arXiv:1110.1031; EPJ A48 (2012) 92)

  25. Design Features: High Polarization All ion rings (two boosters, collider) have a figure-8 shape • Spin precession in the left &right parts of the ring are exactly cancelled • Net spin precession (spin tune) is zero, thus energy independent • Ensures spin preservation and ease of spin manipulation • Avoids energy-dependent spin sensitivity for ion all species • The only practical way to accommodate medium energy polarized deuterons which allows for “clean” neutron measurements This design feature permits a high polarization for all light ion beams (The electron ring has a similar shape since it shares a tunnel with the ion ring) Use Siberian Snakes/solenoids to arrange polarization at IPs longitudinal axis Solenoid Vertical axis Proton or Helium-3 beams Deuteron beam Insertion Longitudinal polarization at one IP Transverse polarization at one IP Longitudinal polarization at both IPs Transverse polarization at both IPs Slide 25

  26. Design Features: High Luminosity • Follow a proven concept: KEK-B @2x1034/cm2/s • Based on high bunch repetition rate CW colliding beams • Uses crab crossing • MEIC aims to replicate this concept in colliders w/ hadron beams • The CEBAF electron beam already possesses a high bunch repetition rate • Add ion beams from a new ion complex to match the CEBAF electron beam • high bunch repetition rate • small bunch charge • short bunch length (sz ) • small b* ( b* ~ sz )

  27. MEIC Accelerator R&D: Electron Cooling Solenoid (15 m) • Electron Cooling in Collider – proof of principle of concept & techniques • Cooling simulations are in progress (collaboration with Tech-X established through an SBIR grant) • ERL circulator cooler (linear optics and ERL) design has been completed • Fast RF kicker concept has been developed, plan to test with two kickers from SLAC • Test of beam-beam kicker concept at FNAL/ASTA facility and collaboration are in planning • Optics design of a cooler test facility based on JLab FEL ERL has been completed injector SRF Dechirper Rechirper (in center of figure-8) A technology demonstration possible using JLab FEL facility MEIC Electron cooler dumper e-Cooler Test Facility @ FEL • eliminating a long return path • could double the cooling rate Required R&D: demonstrate ERL-based cooler concept by 2016 (at FEL/ERL conditions)

  28. Proposed Cooling Experiments at IMP • Replacing the existing thermionic gun in the cooler by a JLab photo-cathode gun (Poelker) • Highly invasive to a user facility Proposed experiments • Bunched electron beam to cool a DC ion beam (New phenomena: longitudinal bunch (Hutton)) • Bunched electron beam to cool a bunched ion beams (need an RF cavity for bunching the ion beams) DC cooler Storage rings for Heavy ion coasting beam

  29. Further ongoing MEIC Accelerator R&D • Space Charge Dominated Ion Beam in the Pre-booster • Simulation study is in progress by Argonne-NIU collaborators • Beam Synchronization • A scheme has been developed; SRF cavity frequency tunability study is in progress • Beam-Beam Interaction • Phase 1 simulation study was completed • Interaction Region, Chromaticity Compensation and Dynamic Aperture • Detector integration with IR design has been completed, offering excellent acceptance • Correction scheme has been developed, and incorporated into the IR design • Tracking simulations show excellent momentum acceptance; dynamic aperture is increased • Further optimization in progress (e.g., all magnet spaces/sizes defined for IR +/- 100 m) • Beam Polarization • Electron spin matching and tracking simulations are in progress, achieving acceptable equilibrium polarization and lifetime (collaboration with DESY) • New ion polarization scheme and spin rotators have been developed (collaboration with Russian group) – numerical demonstration of figure-8 concept with misalignments ongoing • Electron Cloud in Ion Ring • Ion Sources (Polarized and Universal)

  30. MEIC: FullAcceptance Detector 7 meters detectors solenoid ion FFQs ion dipole w/ detectors ions IP 0 mrad electrons electron FFQs 50 mrad 2+3 m 2 m 2 m Three-stage detection Central detector TOF Detect particles with angles below 0.5obeyond ion FFQs and in arcs. Need 4 m machine element free region Detect particles with angles down to 0.5obefore ion FFQs. Need 1-2 Tm dipole. Solenoid yoke + Muon Detector RICH or DIRC/LTCC Tracking RICH EM Calorimeter HTCC 4-5m Muon Detector Hadron Calorimeter EM Calorimeter Very-forward detector Large dipole bend @ 20 meter from IP (to correct the 50 mr ion horizontal crossing angle) allows for very-small angle detection (0.1-0.3o). Need 20 m machine element free region Solenoid yoke + Hadronic Calorimeter 2m 3m 2m

  31. MEIC Point Design Parameters

  32. EIC Realization Imagined Assumes endorsement for an EIC at the next NSAC Long Range Plan Assumes relevant accelerator R&D for down-select process done around 2016

  33. Summary • There has been excellent progress on developing the EIC science case over the last 2 years, with important contributions from both the BNL and JLab communities. White paper now available. • We anticipate an NSAC Long Range Plan in the next 2-3 years – need to realize a recommendation for EIC construction. • MEIC design is stable and mature. R&D planning in progress, with good opportunities for collaboration. • We are hopeful that an international collaboration can develop to advance the science and technology of electron ion colliders.

  34. Y. Zhang, IMP Seminar Announcement EIC14 An International Workshop for Accelerator science and Technology for Electron-ion Collider March 24 – 28, 2014 Newport News, Virginia, USA Welcome to Virginia!

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