HBD upgrade status.

1. HBD upgrade status. Sasha Milov Dec 07, 2005 Sasha Milov DC meeting Dec 7, 2005

2. Progress: • Mechanical assembly • Photocathode production and measurement • Glove Box modification • GEMs testing • Electronics status • Beam test Sasha Milov DC meeting Dec 7, 2005

3. Mechanical assembly. • Mechanical parts are being produced • Delay in the PCB due to changes in the pad design • Finalizing the HV panel design • Good progress in GEM assembly and test. Sasha Milov DC meeting Dec 7, 2005

4. Pad plane design. • Fixed number of electronics channels (192 per sector) needs to be matched with the number of pads. Best solution in the old version eliminates acceptance loss by wiring pads between HV sectors. That might create grounding problems. To avoid that we consider modification of the pad shape at the edges where pads are partially shadowed by GEM frames. That has several advantages: • best grounding • easy to match with Nchannels • no acceptance loss • somewhat smaller pad size (good) a=15.0 mm Sasha Milov DC meeting Dec 7, 2005

5. Pad plane production • Pad plane production is foreseen at CERN ( as done for the full scale prototype). • Quotation is higher than originally estimated (small problem) • Delivery time is 19 weeks !!! (big problem). Negotiations are underway with CERN to speed up production a factor of two at least. Sasha Milov DC meeting Dec 7, 2005

6. New HV panel. • Eliminates the HV divider boxes. Reduces the number of HV cables to the HBD and the number of SHV connectors on the HBD from 168 to 48. • HV dividers should be made smaller to reduce the material and mechanical stress on the detector boxes. Current version is below. • Prototype constructed and tested up to 6 KV without any problem (operating voltage is less than 4 KV). Sasha Milov DC meeting Dec 7, 2005

7. Photocathodes. • INFN evaporator from JLab is at SUNYSB is up and working • vacuum down to 8E-8 mbarr • capable to produce 4 full size at a time • Q.E. control works inside the vessel • Residual Gas Analyzer works inside the vessel • Produced several 10x10 cm2 photocathodes on GEMs (previously used and washed, but fully operational) • Q.E. is controlled during production at SUNYSB and precisely measured at BNL. • Results are: a) reproducible b) as good as best WIS results !!! Sasha Milov DC meeting Dec 7, 2005

8. Glove Box design vs. cost. • GB bids came out x2.5-x5 higher than originally planned. • INFN GB is not a good investment opportunity. • Way out: reconsider procedure to lower cost of the required GB. • Pipe-line gain test & installation rather than doing them in one shot • First the gain test is done on all needed shots for CsI cathodes. • Each successful cathode goes into high vacuum storage. • Only when all needed cathodes are made installation of all cathodes into HBD vessel begins. Such new protocol makes glove box smaller AND takes better care of GEMS. • New bid process for (budget)-lighter table was started yesterday. • Use Laminar Table prior to deposition instead of GB, which provides STRICT control over dust and less that of H2O and O2 but they are not yet an issue. • Laminar table is better solution than using GB (better dexterity). • A working table is in possession, needs fresh filters... on order. • These changes reduce the needed size of the glove box by 2X. • We can additionally reduce the cost by re-engineering the air-lock(flow-through not pumped). Sasha Milov DC meeting Dec 7, 2005

9. Other parts needed. •  Vacuum storage needed for new procedure is the ultimate quality storage for GEM+CsI. • A suitable Stainless steel vessel was found (free) • Missing end-flanges were made ($1800) • Turbo Pump (borrowed) will be removed from NSL beam line 2 weeks from now (free). • Re-assessed overall budget and it seems with the new glove box design we are on track. • Design of full sized GEM holder for evaporator done and in shop. • Ancillary designs (pizza boxes, railroads, flip tables, ...)underway (finished conceptually). Sasha Milov DC meeting Dec 7, 2005

10. GEM testing. • GEM triplet assembled at WIS has ~50% gain variation across the area • Production of other GEMs was suspended to investigate the reasons. • Assembly procedure was found not to be an issue, it is well reproducible. Sasha Milov DC meeting Dec 7, 2005

11. GEM testing. Ratio of single GEM gain product over triplet is flat. That proves that the large gain variations in the triple GEM detector are not due to assembly. The non-uniformities in single GEMs add to a larger effect in the triple GEM module. Strategy: A possible solution to minimize the gain variations in the triple GEM detector is to make all possible combinations of GEMs and to choose the combinations with minimum spread. For that the gain maps of each GEM (corrected for P/T variations) will be stored in a database. CERN production is restored Sasha Milov DC meeting Dec 7, 2005

12. Electronics status (FEE). • Motherboard with preamps is installed on the prototype at BNL. • Signals and noise are under investigation. • Shielding helps a lot! Sasha Milov DC meeting Dec 7, 2005

13. Electronics status (FEE). Test pulse 100,000 e’s 20 pe 1.4 mV  ~ 0.6 pe 1.1 mV  ~ 0.4 pe Outside channel Inside channel HV connected (V=0), all 68 preamps plugged in Sasha Milov DC meeting Dec 7, 2005

14. Gas transmission monitor • Propose going to single test • cell to save $ • Use valves to switch gas • test cell Sasha Milov DC meeting Dec 7, 2005

15. Electronics status (FEM). Optical out – Design is done -- checking New DCM daughter card design is done -- checking For Clockmaster, clock fanout, ADC and backplane, the prototype boards are assembled Crate Backplane (7 blank boards, 4 crates+ 1 spare+ 2 test stands) (7 blank boards, 4 crates+ 1 spare+ 2 test stands) Clock fanout ADC Optical out Test pulse (25 blank boards. We have most of the parts for 5 boards) Clock Master New Daughter card + DCM (4 blank boards, 1 needed + 1 spare+ 2 test stands) GTM/Ethernet Sasha Milov DC meeting Dec 7, 2005

16. LEGS beam test. • Everything was in place and ready to go, besides LEGS magnet. • Got water leak from the repaired coil on the day of operation. This problem cannot be fixed and would require a major repair. • Optimistic forecast brings us to the end of spring. • Other options are very welcomed, like getting beam at AGS. Sasha Milov DC meeting Dec 7, 2005

17. Summary: • Mechanical assembly is on its way. Some modifications are made to the pad plane and HV feed-ins. • CsI Q.E. curve is good and reproducible • Glove Box is reconsidered to match existing budget. Requires slightly different game plan on assembly, but well doable without quality compromise. • GEM testing is important. GEMs will be separately tested at WIS and assembled in triplets to get best uniformity • Electronics has in work. Motherboard is under test with the prototype. • Test beam is needed. LEGS option is still considered, but nothing will happen soon. Sasha Milov DC meeting Dec 7, 2005

18. BACKUPS Sasha Milov DC meeting Dec 7, 2005

19. Clock Master Board Ethernet interface Serial data In/out GTM Input Clock Circuits Sasha Milov DC meeting Dec 7, 2005

20. HBD ADC board FPGA ADC Receiver/ shaping Signals from Preamp Sasha Milov DC meeting Dec 7, 2005

21. HBD ADC crate We have just enough connectors for populating 3 slots 2 weeks ago. Clock Fanout Clock cables Clock and serial data cables from ClockMaster Sasha Milov DC meeting Dec 7, 2005

22. Get the ADC board and backplane middle/late of last week Finish assemble the system Monday morning. Testing is in progress Status Sasha Milov DC meeting Dec 7, 2005

23. HV on, Ar/CO2 (70/30) Positive signals ? 55Fe signal Sasha Milov DC meeting Dec 7, 2005