DC 12 Status Work Plans for FY 10

DC 12 Status, Work Plans for FY 10 • Build boxes – receive, inspect parts – outfit cleanroom with construction tables – assemble boxes • String and instrument chamber – strongbacks and stringing fixtures done – stringers’ platforms and machine in place – feedthroughs, crimp pins, wire on hand November 19, 2009 Hall B meeting Mac Mestayer

Physics goal measure cross-section accurately Physics spec. q ~ 1 mrad dp/p < 1% Design feature planar chambers identical cells (easy to calibrate) 250 mm accuracy/layer select an exclusive reaction; dp <. 05 Ge. V/c e. g. only one missing pion dq p <. 02 Ge. V/c sinq df p <. 02 Ge. V/c ~linear drift velocity +/- 6 o stereo angle small cross-sections L = 1035/cm 2/s high efficiency small cells, 112 wires/lyr. six 6 -layer superlayers 30 mm wires good acceptance Df ~ 50% of 2 p at 5 o low wire tensions self-supporting design November 19, 2009 Hall B meeting Mac Mestayer

Endplates fit into Frames Receive endplates - inspect -clean -measure hole positions Receive frames - inspect and clean - bolt and glue into frames Receive nose and back-plate -assemble boxes back plate endplate frame nose plate November 19, 2009 Hall B meeting Mac Mestayer

Status and work plans … • Build boxes • Status – receive, inspect parts • endplate and frame • nose and back plates – outfit cleanroom with construction tables – assemble boxes November 19, 2009 Hall B meeting – Region 2 endplates and frames on-site, nose and backplates ordered – tables being moved into cleanroom – 1 st box done Mar. 1 Mac Mestayer

Status and work plans … • String chambers • Status – Preparation • lead stringer hired • chamber box built • Mar. 1 – on strong-back • • • – Feb - July stringing fixture assembled stringers’ platforms in place stringing machine feedthroughs, crimp pins wire – String !!! November 19, 2009 Hall B meeting • • • Feb - July on-site electronics shop ordered on-site, testing start Mar. 1 Mac Mestayer

Parts: wire a circuit board signal routing: wires a pre-amp conductive rubber circuit board crimp pin feedthrough endplate wire November 19, 2009 Hall B meeting Mac Mestayer

Stringing wires between “slanted” endplates “gravity” stringing endplates November 19, 2009 wires: 9 cm - 4 m long wires strung individually wires attached by crimping wires positioned by “trumpet” Hall B meeting Mac Mestayer

CLAS 12 Stringing Fixture November 19, 2009 Hall B meeting Mac Mestayer

Steps in Stringing November 19, 2009 Hall B meeting Mac Mestayer

Challenges … • award contract MOU’s to ODU, ISU – universities hire & oversee stringing effort – need to move manpower forward ~1 yr. • thin endplates; max. solid angle coverage – wires sag up to ~1 mm – endplates bow up to ~2 mm • surveys and software corrections essential • quality control November 19, 2009 Hall B meeting Mac Mestayer

Plans for next year: • Buy reg. 1, 3 boxes and fixtures • Build reg. 2 boxes, some others – Reg. 2 lead technician hired – work in Jlab’s, ODU’s cleanrooms • Inspect wire, feedthroughs, crimp pins • Build strong-backs, installation fixtures • String first Reg. 2 chamber – hire, train next 2 lead stringers November 19, 2009 Hall B meeting Mac Mestayer