g2p/GEp Preparation Overview

Jian-ping Chen g2

p /Gep Readiness Review 5/6/2011

REGION 1

REGION 2 REGION 3 REG 4 REGION 5

Slow Raster

FZ1FixedStand

FZ2 Telescoping Stand

DUMP

TARGET

•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

BPMs

Use existing equipments Hall C beamline/target

Keep change minimum

modify the existing PREX septa

Major equipments for g2p/GE

p experiments

Septa/HRS

•Goal is to measure g2p in the low Q2 region with a precision ~ 5-7% by measuring transversely polarized cross section difference = A x 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%)• …

Experimental Goal/Considerations

•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

Overview of Progress (I)

•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

Overview of Progress (II)

3.4 GeV, 12.5 deg2.3 GeV, 12.5 deg

3.4 GeV, 6 deg2.3 GeV, 6 deg1.7 GeV, 6 deg1.2 GeV, 6 deg

Polarized beam: 50-130 nA up to 1 uA for optics

Polarized NH3 target at 5T, 1KSlow Raster 20-25 mm diameter

Gep configuration is basically g2

p 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)G2

p : target at 90 degrees for all and 0 degree for 3.4 GeVGE

p : target at 20 degree

Kinematic Settings (target field effect not taken into account)

3.4 GeV, 12.5 deg2.3 GeV, 12.5 deg

3.4 GeV, 6 deg2.3 GeV, 6 deg1.7 GeV, 6 deg1.2 GeV, 6 deg

Polarized beam: 50-130 nA up to 1 uA for optics

Polarized NH3 target at 5T, 1KSlow Raster 20-25 mm diameter

Gep configuration is basically g2

p 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)G2

p : target at 90 degrees for all and 0 degree for 3.4 GeVGE

p : target at 20 degree

Kinematic Settings (WITH target field effect)

3.4 GeV, 12.5 deg2.3 GeV, 12.5 deg

3.4 GeV, 6 deg2.3 GeV, 6 deg1.7 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 impacts1) 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) GE

p : target at 20 degree, smaller effects.

Kinematic Settings (Proposed New Settings)

• Target safety:Following all the safety considerations as in SANE experiment in Hall CAdditional 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

Safety Considerations and Documents

• 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)

Budget and User Contributions

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) …

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)

• 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

Schedule and Milestones