Super BigBite concepts Bogdan Wojtsekhowski, JLab Physics requirements Some experiments Layout for the GEP-15 Proposed spectrometer Detector configuration Expected parameters Stages of implementation

Physics requirements Generic experiments to consider: Requirements: Inclusive (e,e’) - pol DIS Exclusive (e,e’N) - GEP/GMP Semi-inclusive (e,e’h) - SIDIS Requirements: Solid angle - > 20 msr Scattering angle - 5-30 deg. Momentum range - 1-8 GeV/c

Some of Experiments GMN with 6 GeV beam (Q2 up to 8 GeV2) Many experiments for 11 GeV beam: GEP - unique kinem. correlation -> L ~ 1039 A1n/d2n; A1p/dp; Transversity (e,e’) and (e,e’K+/-) FFs with polarized target - GEN, GEP

GEP-15 layout

Design considerations Vertical bending Detector should be behind magnetic field Compact beam spot on the target Simple dipole is the best for large momentum bite Field integral and bend angle vs detector resolution Progress in tracking detector technology

Proposed Spectrometer Magnet of 100 tons with aperture 46 cm x 122 cm full 3 Tesla-meter field integral Detector package:- GEM trackers resolution: 0.07 mm - Calorimeter based trigger > 1 GeV - Lead-glass PID for electron - Fast RICH from HERMES for ,K How to put a wide magnet at 10o angle near the target? Iron yoke is cut off to allow for the beam pipe!

Small angle concept

Layout of SuperBigBite 2-nd arm RICH Preshower Shower

Parameters mrad msr Momentum acceptance at full field - 2 GeV/c and higher Momentum resolution ~ 0.5% for 8 GeV/c Solid angle at 14 degree is 55 msr (72” from pivot to yoke) Solid angle has aspect ratio 1:2.5 Angle resolution of 0.3 mrad Vertex resolution of 1 mm Target length 40 cm Simple optics, flat acceptance - perfect for terms like sin2 mrad 5 10 15 20 msr 13 38 58 85

The 48D48 magnet at BNL 100 tons, 18.5” x 48” x 48” field volume

GEM base tracker Rate capability ~ 10 kHz/mm2

Best PID: fast RICH -like in HERMES Sensitive area ~ 60x200 cm2 viewed with 1934 PMTs

Plans Development will be driven/funded by the GEP-15 collaboration Components reused are a magnet and both calorimeters Proposal GEP/GMP (GEP-15) is submitted to the PAC32 Proposal GMN/GMP is under preparation to the next PAC GMN with the magnet - before 2011 at 50% field ( 1/4 power ) Support stand and full power for the magnet (refurbished BNL’s) Construction of the tracking detectors - BIG NEW! I - 10x10 cm prototype, II- 40x140 cm prototype Franco’s collaboration: INFN+Glasgow+UVA+FIU+JLab Reconstruction of the hadron calorimeter - W&M+Dubna More proposals are under development for 12 GeV PACs Possible second arm magnet for the J/