BigBite Spectrometer Equipment by Douglas W. Higinbotham

BigBite Family of Experiments Threshold Pion Production (Hadron Package) {Cryo-Target} Transversity & d2 (Electron Package) {3He Target} Ay (HRS) & (e,e’d) (Hadron Package) {3He Target}

BigBite Infrastructure For Transversity Magnet Continues To Work Without Issue (one spare coil) Power Supply Has Had Only Minor Problems –Problem Tends To Be With Communication –We Rarely Change Field, So Not Big Issue –Technicians Have Tried To Fix This Extremely Tight Space To Get To 30 Degrees –New Right Foot Designed and Ordered –Work On Beam-line Area Needs To Be Done (Folts) GEN Field Clamp Extended Re-use GEN Side Shielding Add Better Internal Shielding (Multi-Experiment Problem)

BigBite Detectors For Transversity Three Full Wire Chambers –Send Middle Chamber To UVa During March –Designer Assigned –Upgrade Chamber Major Item For Review Trigger Scintillators PreShower & Shower Detector –Several PMTs Marginal (near 2kV) and Few Dead –Either Buying 60 PMTs or 10 PMTs NEW Gas Cherenkov Designed by Brad –Major Item For Review –Asked JLab For 60k This FY For This Project

Wire-Chamber Electronics We have both VME and Fastbus! Though would need four more VME units for middle chamber read-out. 200 pre-Amp cards and associate equipment in production. –Over 100 have been delivered. –Rest In The Electronics Group’s Queue 40 more pre-Amp cards are being ordered. 210 needed for three 6 plane chambers (240 total order)

Electronics and Cables All experiments will share wirechamber electronics. The pi0 & (e,e’d) experiments will be using mostly their own NIM/CAMAC electronics. d2 and Transversity NIM/CAMAC electronics converging, BUT not yet finalized. –Brad is adding Cherenkov to trigger setup –Must be done in the coming week! –Albert Coming To Help Supervise Construction

Test Lab All BigBite experiments share the test lab space. –Douglas Manages The Space –Eugene Is Area Safety Warden Bertha Power Supply (440V) Needs To Be Moved To Test Lab –Single Source Of Power –Solves Outlet Problem and Hopefully Grounding Problems Safety Is Important –Some Items Need Safety Procedures –Procedures Needs Many Signatures Once GEP III Leaves, We Will Get Some Space Back BUT, It Will Continue To Be Very Crowded –Work Safely!