Physics Division Town Meeting

December 8, 2011

Hall C after 12 GeV Upgrade

• Beam Energy: 2 – 11 GeV/c• Super High Momentum

Spectrometer (SHMS)– Horizontal Bender, 3 Quads, Dipole– P 11 GeV/c– dP/P 0.5 – 1.0x10-3

– Acceptance: 5msr, 30%– 5.5 < < 40

• High Momentum Spectrometer (HMS)– P 7.5 GeV/c– dP/P 0.5 – 1.0x10-3

– Acceptance: 6.5msr, 18%– 10.5 < < 90

• Minimum opening angle: 17• Well shielded detector huts

• Compton and Moller beam polarimeters

• Ideal facility for:– Rosenbluth (L/T) separations– Inclusive & Exclusive reactions– Low cross sections (neutrino level)

Number Experiment Grade Approved Days Conditionally Non-standard Equipment

E12-06-101 Pion Form Factor A 52E12-06-104 SIDIS R A- 40E12-06-105 x>1 A- 32E12-06-121 He3 g_2 A- 29 Polarized He3 targetE12-07-105 (e,e'p ) Exclusive Factorizaton A- 36E12-09-011 (e,e'K) Exclusive Factorization B+ 40E12-09-017 SIDIS P_t A- 32E12-09-002 Charge Symmetry Violation A- 22E12-10-002 F2 @ large x B+ 13E12-10-003 d(e,e'p) B+ 21E12-10-008 EMC A- 23E12-06-107 Color Transparency B+ 26E12-06-110 He3 A1n A 36 Polarized He3 targetE12-11-002 He4(e,e'pol(p)) B+ 37 FPP in HMSE12-11-009 Neutron Form Factor B+ 50 Magnet + Neutron polarimeterC12-11-102 Exl and semi-exl p0 prod C2 69 p0 detectorE12-11-107 EMC d(e,e' backward p) B+ 40 LAD (Hall B TOF bars)

529 69

Total 598 Days 6.8 Years @ 25 Weeks/yearSchedule 2 days / PAC day

Approved and Conditional 12 GeV Hall C Experiments

Hall C 5-10 years after upgrade

• Maintain unique Hall C capabilities• High momentum• Low cross sections• L/T separations

• Maintain ability for large installations/new facilities driven by physics

• 0 detector

Inclusive/exclusive p(e,e0)• Large solid angle detector for backward nucleons

EMC/SRC• Reinstall HKS and HKS spectrometers

A(e,eK+)• Calorimeter for J/ detector

N J/ scattering length

An (e,e0) L/T facility in Hall C

RSIDIS RDIS disappears with Q2!

• Use HMS as precision electron arm for L/T

• Remove SHMS HB magnet, install 0.3 Tm sweeping magnet (copy features of HB to minimize stray field on beam)

• Add 25 msr p0 detector using 1116 PbWO4 blocks (with new temperature-controlled frame)

• Cantilevered platforms of SHMS carriage (rotatable between 6 and 29 degrees)

• Augment p0 detector with new PMT bases & flash ADCs

• Dedicated beam pipe with large critical angle + shielding

HMS

target

Beam direction

Backward nucleon detector – EMC effect

Recycled CLAS6 TOF detectors

SHMS

HMS

HKS/HES in 12 GeV Hall C A(e,eK+) - One pass beam, low beam currents

Compatible with a high energy/current parity program

HES e- HKS K+

HMS

SHMS