(JG-Uni Mainz & Fermilab), Diego Gonzalez Diaz, Naseem Khan, Tanaz Mohayai
Some notes from ADM....
TOAD - Naseem
Getting servers on FNAL network and can now ssh into them. Working on slow control and light readout with camera. Need to fix focus on camera and can control camera. Can potentially operate in vacuum soon. Engineering note for high pressure under review.
GOAT - Tanaz
Have seen some deformities on wires on original ALICE calibration chamber. Switched to a new ALICE production chamber. Gain is much improved and can now see nice 55Fe source spectrum and escape peak at atmospheric pressure. Once optimized, will move to GOAT pressure vessel and resume high pressure testing in near future. Also showed a anode voltage scan plot.
On GEM side, TPC should ship soon from Tectra. Would like to compare/contrast GEM and ALICE MWPC performance. GEM comes with its own readout board and electronics. In later stages, will try to read it out with SAMPA or other options.
Showed a spectrum. Signal/valley ratio could be better. Reading out just a few pads ganged together into one channel, so might be missing some oft he induced charge. Will try to add a few more pads to readout. But things are very close. Noise is also very good (using now an Ortec shaping amp and Cremat pre-amp). Nominal gain around 15,000 right now.
Light Collection studies & GAT0 - Diego
Have circulated a paper draft on light collection simulation. Want to get out papers on primary scintillation and spectroscopic analysis out by the end of the year too. On hardware side, talking to Iowa about LAPPDs. Might be promising, and will try to re-evaluate together the light sensitivity and threshold. Also working on development of light collection. Also mounted the new ganging board at IFIC. Still in progress and hope to have signals soon. Also with Vigo developing an active cryostat to stabilize the temperature. Gas distribution studies progressing slowly (with Vigo now) and also with Philip at Mainz. For tracking planes have looked at GEMs with acrylic and glass substrates. Organized a small scale structures workshop. On physics side, have moved from Geant4 simulations to S1 reconstruction in the presence of pileup. Trying to see if can reconstruct 5 MeV single deposits (Miral). The GAT0 TPC is being reassembled into a new config. Have designed new reflectors and new insulator and they are being manufactured. They have thick “fat” GEMs. Want to commission at 1 bar and reconstruct with a CCD camera. Then move to higher pressure and eventually include TimePix.