GlueX Simulations Status Report on CD3 geometry Richard Jones GlueX Collaboration Meeting, Newport News, January 10-12, 2008

GlueX collaboration meeting, Newport News, January 10-12, Detector subsystems  Target - unchanged  Start Counter - updated  Central Drift Chamber - updated  Forward Drift Chamber - updated  Barrel Calorimeter - updated  Upstream Calorimeter/Veto – removed  Gas Cerenkov - updated  Time-of-Flight counter - unchanged  Forward Calorimeter - unchanged  Solenoid / magnetic field – updates in progress

GlueX collaboration meeting, Newport News, January 10-12, Target - unchanged  liquid hydrogen volume diameter 3 cm length 30 cm kapton walls 150 m thick  vacuum chamber walls 1 cm of high-density (0.11 g/cm 3 ) ROHACELL exterior diameter 8 cm  vacuum entrance, exit windows 70 m of aluminum

GlueX collaboration meeting, Newport News, January 10-12, Start Counter - updated  layer structure high density ROHACELL r= cm scintillator 2.15 mm thick low density ROHACELL r=7.69 – 8.68 cm cellulose wrapping tape 0.5 mm thick  forward tapered section first conical section 22.5° taper second conical segment 45° taper all layers constant thickness innermost diameter 4.58 cm

GlueX collaboration meeting, Newport News, January 10-12, Central Drift Chamber - updated  active length shortened to 150 cm  two options for stereo layer sequence option 1 1.stereo layers 4-7 and sequence -,-,+,+ in each option 2 1.stereo layers 4-6, 12-14, sequences -,-,- ; +,+,+ ; -,-,-  trade-off issues polar angle resolution track finding / pattern recognition

GlueX collaboration meeting, Newport News, January 10-12, Forward Drift Chamber - updated  changed package positions compressed in z last package in stronger field region  different dead region in each package 2.3 cm, 3.2 cm, 3.9 cm, 4.6 cm  important reduction in outer radius of active region now r=48.5 cm allows space for HV coupling capacitors  detailed sandwich repeating structure for frames  important new materials at r=60cm for cooling 0.5 mm copper cylinder around frame periphery 0.7 mm aluinum cylinder between packages

GlueX collaboration meeting, Newport News, January 10-12, Barrel Calorimeter - updated  overall dimensions unchanged  new readout segmentation scheme innermost 12 cm covered by 4 (phi) x 6 (depth) 2 x 2 cm 2 cells with Winston cones and SiPMs. outermost cm covered by 2 x x 5.04 cm 2 cells with light collectors, light pipes  readout scheme specifies coupling with Winston cones of uniform 2 x 2 cm 2 collection area large gaps appear in phi at outer layers coverage ranges from 92.6% (layer 1) to 80.4% (layer 6) for inner layers, 96.7% % outer layers may affect energy resolution, should be studied only energy in readout cells is seen in simulation

GlueX collaboration meeting, Newport News, January 10-12, Barrel Calorimeter - updated  total channel count settled 2304 SiPM channels (upstream + downstream 384 outer channels (several per Planacon?)  routing of light pipes not shown, probably doesn’t matter because outside acceptance

GlueX collaboration meeting, Newport News, January 10-12, Upstream Veto – removed  commented out

GlueX collaboration meeting, Newport News, January 10-12, Gas Cerenkov Stand-alone Monte Carlo toy model of Cerenkov optics, Eugene Chudakov This mirror geometry is now in HDGeant. Optical properties by E. Chudakov

GlueX collaboration meeting, Newport News, January 10-12, Time-of-Flight counter - unchanged  two layers 2.54 cm thick square area 255 cm on a side square beam hole 12 cm on a side unwrapped in simulation, probably ok

GlueX collaboration meeting, Newport News, January 10-12, Forward Calorimeter - unchanged  quasi circular, radius 29 x 4 cm  beam hole 3 x 3 blocks  nothing special for beam-hole region  energy deposition response model

GlueX collaboration meeting, Newport News, January 10-12, Solenoid / magnetic field  uniform field in azimuth  map coverage from 4 cm to 254 cm  linear extrapolation outside mapped region probably inaccurate in downstream region update underway to new larger map new map dimensions ?? CD3 studies should use the new map

GlueX collaboration meeting, Newport News, January 10-12,

GlueX collaboration meeting, Newport News, January 10-12,

GlueX collaboration meeting, Newport News, January 10-12,

GlueX collaboration meeting, Newport News, January 10-12,

GlueX collaboration meeting, Newport News, January 10-12,