1. G0 Detector Working Group Meeting
G0 GMS Update
S. Pate, NMSU
G0 Detector Working Group Meeting
17-July-1998
hardware, costs, schedule, …
FPD/CED scenarios and how they “interface” to the GMS

2. GMS Schematic

3. Optics

4. Cluster Assembly Mechanical

5. Fiber Cluster Layout

6. Selector Mechanism

7. Cost

8. Schedule
Phase I -- Items needed to build and develop the system:
laser, optics, container, safety goggles, some fibers
and connectors
Phase II -- Items needed to complete the system:
cluster assembly, balance of fibers and connectors,
calibration source, masking system
Oct 1998 Start purchasing process on phase I
Nov 1998 Vendors actually receive PO's for phase I
Jan 1999 Delivery of Phase I items to NMSU
Feb 1999 Construct and test; Start purchasing for phase II
Mar 1999 Vendors receive PO's for phase II
May 1999 Delivery of phase II items to NMSU
Jun 1999 Test
Aug 1999 Delivery to JLab

9. FPD/CED Scenarios --- Comparisons
Plan A
Assumptions:
Front & Back FPD’s, & CED’s
Each scintillator gets a single fiber at its center
Back FPD light redirected to CED for electron running
Notes:
Total configuration control
“Mean” timing and pulse height for offline setup
Little knowledge of source of any observed deviations over time

10. Plan B
Assumptions:
Front & Back FPD’s, & CED’s
Each pair of FPD’s illuminated at both ends; each end has a single fiber which illuminates both scintillators
One side of FPD light redirected to CED for electron running
Notes:
Monitor FPD gains and scintillator attenuation separately
No center spine required in FPD mounting assembly
Asymmetric FPD GMS operation for electron running
No FPD can view every laser pulse and act as a monitor

11. Plan C
Assumptions:
Front & Back FPD’s for protons; Hodo for electrons
Each pair of FPD’s illuminated at both ends; each end has a single fiber which illuminates both scintillators
Each Hodo element gets one fiber
Notes:
Monitor FPD gains and scintillator attenuation separately
No center spine required in FPD mounting assembly
Separate configuration control for FPD and Hodo
No FPD can view every laser pulse and act as a monitor