1. Minimum Bias Trigger Scintillators (MBTS) a project of: CERN Dubna Michigan State University University of Texas-Arlington presented by J. Huston Michigan State University (apologies: some useful drawings captive on laptop, in for repairs)

2. MBTS counters 2 segments in  ; inner segment covers pixel detectors

3. Readout Scintillator is polystyrene- based, 2 cm thick Readout is by WLS fibers running along division between L/R scintillator segments plus through sigma grooves in scintillator Struggle to be able to trigger on MIP’s  increase light yield using every trick we know Will also crank up HV to 900 V WLS fibers welded to clear fibers to produce a pigtail which will mate into 1/8 of cryostat scintillator optical connections  after commissioning cryostat detectors will be re-connected

4. Scintillator Scintillator has been produced by Dubna  same scintillator as used for CDF central pre-radiator upgrade  currently at CERN, awaiting shipment to MSU later this week  ~2.5 month delay…  …construction will still be complete in September  will continue to test counters using ATLAS electronics readout chain at the U. of Chicago  …and installation will take place this fall/winter

5. Preliminary mounting scheme …making use of mounting holes in cryostats

6. New decision MBTS scintillator and boronated polyethylene moderator will be mounted together in same can  MBTS counters are never removed; they just slowly die but continue to moderate Moderator has to be machined back to 30 mm  currently looking for vendor  envelope of MBTS + moderator is 57 mm

7. New drawings of moderator + MBTS …still have to be approved

8. MBTS drawings

9. Installation work This fall/winter, the gap and cryostat scintillators will be installed on EBA and EBC  maybe delay in current schedule, but roughly Nov and Jan During these times, teams from the institutions listed on front page will be at CERN and will also work on installation of MBTS counters + moderator  working with shielding group  all details not worked out yet, but Ron Richards is at CERN for next few weeks to coordinate  installation is designed to be relatively straightforward