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g2p/GEp Preparation Overview

g2p/GEp Preparation Overview. Jian-ping Chen g 2 p /G ep Readiness Review 5/6/2011. Major equipments for g 2 p /G E p experiments. Polarized Solid NH 3 Target (Hall C/UVa target) Target material irradiation

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g2p/GEp Preparation Overview

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  1. g2p/GEp Preparation Overview Jian-ping Chen g2p /Gep Readiness Review 5/6/2011

  2. Major equipments for g2p/GEp experiments • Polarized Solid NH3 Target (Hall C/UVa target) • Target material irradiation • Beamline (Similar to Hall C) • Magnetic Chicane/Beamline modifications. • Low beam current BCM/BPMs, Slow Raster • Hall A Engineering/Design • Local Beam Dump • Septum Magnets • Hall Infra-structure/Chamber/ Target/magnet mount • Simulations/Optics/Spectrometer/Detectors/QAD • Polarimetry/3rd arm Use existing equipments Hall C beamline/target Keep change minimum modify the existing PREX septa FZ2 Telescoping Stand FZ1 FixedStand BPMs Slow Raster TARGET Septa/HRS DUMP REGION 1 REGION 2 REGION 3 REG 4 REGION 5

  3. Experimental Goal/Considerations • Goal is to measure g2p in the low Q2 region with a precision ~ 5-7% • by measuring transversely polarized cross section difference = A x s • Measure both asymmetries and cross sections to 4-5% • In addition to statistics, we need to control total systematics to 3-5%, i. e., each system • to be below that (1-3%). • Main systematics for asymmetries: • Target polarization (3-4%) • Beam polarization (2-3%) • Dilution factor/packing factor (some cancellation) • Main systematics for cross sections • Acceptance/optics (~3%) • Dilution factor/packing factor (some cancellation) • Density (2-3%) • Beam charge (1-2%) • Position and angle determination (0.1-0.2 mm, 0.03-0.05 degree) • Detector efficiencies (~< 1%) • Background (pions, …) (1%) • Radiative corrections (including radiative tails) (1-4%) • …

  4. Overview of Progress (I) • Significant Progress in Beam Line System (T. Michalski, weekly meeting) • Overview design, Region 1 and Region 2 design completed (B. Dillon-Townes) • Region 3 design near completion • Existing hardware items (magnets, raster, power supplies) located • Most parts are ordered, machined, arriving • New items (BPM/BCM electronics, Harps, BD magnets) are being taken care of • BPM tests (J. Musson) • BCM tests (A. Camsonne/P. Zhu) • Silver Calorimeter • Installation plan worked out with the 6-month-down master plan • Safety/PSS • Target Progress (C. Keith, bi-weekly meeting) • Magnet repaired and back to JLab • Design progressing well • Parts are being ordered, manufactured • Rotating Seal • Target insertion • Target material irriadiation at NIST planned (June, D. Crabb) • Cold-down test • Alignment • Cryogenics • Full polarization test • Safety consderations

  5. Overview of Progress (II) • Hall A infrastructure, Beam dump, Septum (A. Gavalya, frequent meeting) • Pivot platform layout • Septum modification completed (Ed) and tested at low current. • Septum field effects on target (Robin Wines) • Scattering chamber • Beam dump • Radiation consideration • Simulations/HRS with septa (Jixie Zhang, Min Huang,… weekly meeting ) • Target field effect on kinematics • Run plan optimization (Karl) • Optics/calibrations • Polarimetry: • Moller (old-style), will work with both straight-through and chicaned beam • 3rd arm detectors (K. Allada, C.Gu) • Monitoring (relative) beam and target polarizations • Detect protons at 72 degrees • Simple DE (thin) & E (thick) scintillators

  6. Kinematic Settings (target field effect not taken into account) 3.4 GeV, 12.5 deg 2.3 GeV, 12.5 deg 3.4 GeV, 6 deg 2.3 GeV, 6 deg 1.7 GeV, 6 deg 1.2 GeV, 6 deg Polarized beam: 50-130 nA up to 1 uA for optics Polarized NH3 target at 5T, 1K Slow Raster 20-25 mm diameter Gep configuration is basically g2p at the elastic setting Two configurations: with septa (6 degree) (target at 87 cm upstream) and without septa (12.5 degrees) (target at original pivot) G2p : target at 90 degrees for all and 0 degree for 3.4 GeV GEp : target at 20 degree

  7. Kinematic Settings (WITH target field effect) 3.4 GeV, 12.5 deg 2.3 GeV, 12.5 deg 3.4 GeV, 6 deg 2.3 GeV, 6 deg 1.7 GeV, 6 deg 1.2 GeV, 6 deg Polarized beam: 50-130 nA up to 1 uA for optics Polarized NH3 target at 5T, 1K Slow Raster 20-25 mm diameter Gep configuration is basically g2p at the elastic setting Two configurations: with septa (6 degrees) (target at 87 cm upstream) and without septa (12.5 degrees) (target at original pivot) G2p : target at 90 degrees for all and 0 degree for 3.4 GeV GEp : target at 20 degree

  8. Kinematic Settings (Proposed New Settings) 3.4 GeV, 12.5 deg 2.3 GeV, 12.5 deg 3.4 GeV, 6 deg 2.3 GeV, 6 deg 1.7 GeV, 6 deg (2.5T) 1.2 GeV, 6 deg (2.5T) Lower target field from 5T to 2.5T for two lowest energy settings (Raise target by 9 cm for the lower 3 settings) Try to minimized impacts 1) 2.5 T leads to lower polarization and time needed for NMR and switch-over. 2) 70 GHz EIO (Don, ok), nose piece (target group). 3) Addition optics settings for beam (Yves, done) and chicane settings (Stephanie, done). 4) Beam dump, scattering chamber (Al). 5) GEp : target at 20 degree, smaller effects.

  9. Safety Considerations and Documents • Target safety: • Following all the safety considerations as in SANE experiment in Hall C • Additional controls in the target area (Chris/Ed/Tim) • Beamline safety: • PSS system to include new changes (Chicane/target/dump) (Tim) • Ion chambers, viewers, thermal couples (dump) • Radiation consideration: • LC dump design: worked closely with RADCON group (Al) • RADCON group helped with calculations of radiation levels • Safety documents: • RSAD (draft) already done • Will work closely with RADCON group to have other radiation related • documents in place • ESAD for each sub-systems will reflect new changes

  10. Budget and User Contributions • Cost: A) Procurement part consistent with initial estimation within expectation • Beam line procurement: 14 BMP electronics (absorbed in Hall A cap, ok) • B) Manpower • Service provider (engineering) significant increase (resolved now, ok) • FY11 addition funding from DOE has been confirmed on the way. • User groups contribution to procurement/machining : • UVa (Don/Donal): target magnet repair, material irradiation • Temple (Zein-Eddine): procurement • Rutgers (Ron): machining + procurement • UVa (Nilanga): machining • HUJI (Guy): machining + procurement • UNH (Karl): procurement • Nice to have these contributions • Users will continue to contribute during installation period • Users onsite manpower build up nicely (next slide)

  11. Onsite User/Hall A People Power • PhD Students: (5-7) • Pengjia Zhu (USTC, advisor: Yunxiu Ye), 3rd year, onsite, (beamline, target) • Min Huang (Duke, Haiyan Gao), 3rd year, onsite, (simulation, optics, HRS)) • Chai Gu (UVa, Nilanga Liyanaga), 2nd year, onsite, (3rd arm, simulation) • Melissa Cummings (W&M, Todd Averett), 2nd year, onsite from 5/2011, (HRS) • Ryan and another (New Hampshire, Karl Slifer), 2nd year, onsite from 5/2011, (run plan) • A student from Temple (Zein-Eddine Meziani), 2nd year, onsite from 5/2011? • Postdocs: (3 + a few part time) • Kalyan Allada (Hall A), beamline, 3rd arm • Jixie Zhang (Hall A): simulation, optics • James (UVa New Hampshire): target, starting in the summer • Xiaohui Zhan (Argonne) (onsite now), busy with other tasks (x>2 experiment) • Narbe Kalantarians(UVa): part time • Hovhannes Baghdasaryan (UVa): part time • Sarah Philips (New Hampshire): part time? • Physicists: • Jian-ping Chen (Hall A): Project manager, overall coordination • Alexandre Camsonne (Hall A): Beam line, DAQ • Karl Slifer (New Hampershire): Overall consideration, run plan, … • Guy Ron (HUJI): GEp consideration • Doug Higinbotham (Hall A) (more available after SRC experiments) • …

  12. People Power and Tasks • Overall coordination: • Project manager (Jian-ping Chen, Hall A) • Project coordinator for beamline (Tim Michalski, engineering division) • Collaboration contacts: Karl Slifer (g2p), Guy Ron (GEp) • Beamline • Engineering Division/Accelerator Division (Tim Michalski coordinator) • Engineer/design (Butch Dillon-Townes) • Installation (Neil Wilson) • Instrumentation/magnets/vacuum/alignment/software/radcon groups, • as identified in 6-month-down schedule/planning • Users (Alexandre Camsonne and Pengjia Zhu) on BCM/BPM/Slow raster… • Target • Target Group (Chirs Keith) • UVA(Don Crabb, Donal Day, psotdocs and students) • New Hampshire (Karl Slifer, James Maxwell) • Other postdocs/students • Hall A engineering/design: Septa/LC Dump/Pivot Layout … • Hall A engineering/design team (Robin Wines, Al, Gavalya) • With input from the collaboration • Hall A installation • Hall A installation team (Ed Folts) • Simulation/optics/HRS/detectors/DAQ/3rd Arm • Users(Physicists/postdocs/students)

  13. Schedule and Milestones • Main Items, each has it’s schedule and milestones (separate talks) • Beamline • Target • Hall infrastructure, beam dump, septa • Installation • May, 2011, Main design complete. • End of May, 2011 Target magnet cool-down in EEL • July, 2011, Parts manufactured and arrived • Aug 3, 2011, Beamline region 1 installation complete • Aug 16, 2011, Beamline region 2 installation complete • Mid-late Aug, 2011, Target test in EEL • Sept 1, 2011, Septa, LC beam dump, scattering chamber installed. • Sept 1, 2011, Target move to Hall A for installation • Sept 15, 2011, Beamline region 3 installation complete • Oct 1, 2011, Dump/target/magnet/chamber alignment complete • Oct 10, 2011, Beamline alignment complete • Nov 14, 2011, Target cool-down/polarize • Nov 19, 2011, Experiment Commission Starts • Jan 23 – March16, 2012, Remove Septa, Move Target back to Pivot • May 2012, End of experiment data taking

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