**attending:** jose, amanda , mayly, bob, matt w, jonathan, francesca, roberto, frank, steven ====== Preliminary discussion ====== FOA for WINP may come soon, on the time scale of a few months, not clear how ANNIE would fit in... Matt W discussed milestones and decision points we need to make soon, particularly choosing a water volume. There was a brief discussion about the MRD, particularly the DHCAL. We announced a meeting that will be at 9:15am, CT on Tuesday. Bob: can we keep both MRDs? should we contact Tim Bolton? Matt W: maybe and yes. ====== TANK OPTIONS ====== Steven Dazeley: Plastic tanks have UV stabilizer (will absorb a lot of the Cherenkov light). We can talk to the manufacturer - do they put it in the resin? Polypropylene is what we would want, not polyethylene But, in any case we can always use a PVC liner Nice thing about the steel tanks (as opposed to plastic) is that one has en easier time mounting and attaching fixtures like the liner and any platforms etc. Tank was steel ~40 tons - the tank was cheap but there was cost to build it in the space WATCHBOY didn't go with plastic, because it was hard to transport a fully pre-assembled detector into the space, but that isn't necessarily a constraint for us Jonathan pointed out that custom polyethylene tanks are a little spotty in the precision of the dimensions (+/-) 10cm, but that may not be a concern for us. Frank: HAWC collaboration has experience with steel tanks + PVC bladders [[http://de.arxiv.org/abs/1408.3477v1]] Bob: Water purification will likely happen first, then we add Gd, then we would operate without further continuous filtering. We could have a continuous filtration system, but it'll cost us. Mark has something at Irvine (100 liter system) but the Davis one wouldn't work in that case We need to think about floor space for the filtration, in the hall, and plan for a submersible pump. May want to look at nitrogen bubbling to keep out Oxygen corrosion and reduce biologics. Steven: WATCHBOY had ~10m attenuation lengths after a year(?) of use (without purification). (WATCHBOY doesn't have GdSO4, GdCL) ====== WATCHBOY readout ====== Steven- Disassembly of watchboy will take ~ 1 month Do we need/want the WATCHBOY PMTs? 10" hammamatsu PMTs in the target have mu metal shielding (which we may or may not want) 3 Modules of HV - 12 channels per module electronics - splitter boxes to pick off the signals 4, 16 channel waveform digitizers (brand?) - 250 MHz, 14 bits all of the system fits into 1 VME crate (waveform digitizers and HV) Max of 64 readout, channels. 52 are used. 48 channel HV, so some are doubled up. More could be doubled. Frank: are the modules relatively modern? Steve: 2 years old Frank: Iowa may have a spare readout software for DAQ is internal and not sure it's public - talk to SANDIA Bob: who at Sandia to talk to? Steven: Peter Marleau ( I will email him ) Amanda: it will be important to figure out what is or is not proprietary Steven: trigger is a sum PMTs are organized into groups of 4 each (summed together), If any group of 4 sets off a trigger - all PMTs are independently read out more details about the design to be sent along. I will post on the wiki.