Oct 26, 2010 Calibration/Monitoring

Teleconference Time: 09:00 CST (Regina) /18:00 GMT+2 (Athens)

• Direct Polycom point-to-point connection

Items for followup from previous meeting(s)

1. Athens test results on Wico vs Trap light guides

Tentative Agenda

1. Followup items
2. Goals/objectives of BCAL calibration/monitoring system
3. Calibration methods
4. Discussion of light transport by fibres or direct LED mounting
5. Athens MOU

Minutes

Attendees: Christina, George V., Pavlos (Athens), George L., Zisis (Regina)

1. Followup item; Wico vs Trap light guides
   1. GV's September measurements shows that within error the Wico and Trap light transmission is the same. Also, simple contact of LG to PMT vs optical grease in between resulted in a 40% loss of light for both Wico and Trap configurations. GV will repeat the measurements this time with a 1mm air gap in between LG and PMT. It was felt that there is no pressing need to mask the PMT's window to the SiPM areal size, but if time permits GV will have a look at it.
   2. The Athens and Regina groups feel that any sacrifice of light for mechanical expedience should be seriously considered as this would impact the reaction thresholds at low energies, particularly in light of the expected SiPM degradation with time due to neutron radiation exposure.
2. Goals/objectives of BCAL calibration/monitoring system
   • The Athens-Regina group supports the following objectives for the proposed system:
   • An absolute energy/gain calibration is beyond the scope of this system and can be extracted
3. Calibration methods
4. Discussion of light transport by fibres or direct LED mounting
5. Athens MOU