Faculty of Physics, University of Belgrade Collaboration meeting, Dubna 8 th of April, ToF-LR Upgrade Jovan Puzović, Faculty of Physics, Belgrade

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 2 out of 24 Jovan Puzović, Belgrade SHINE team ToF-LR HV upgrade -Current status: 1) 2 Caen crates (right 1 and 2) replaced with BG crates 2) Both crates connected via RS485 link to computer in counting room 3) Connection established, beta version of monitoring program working well

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 3 out of 24 Jovan Puzović, Belgrade SHINE team ToF-LR HV upgrade All hardware finished!

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 4 out of 24 Jovan Puzović, Belgrade SHINE team ToF-LR HV upgrade -Crate R3 already in CERN, wait to be installed, Crate R4 still in Belgrade -All distributors (HV readout) have to be calibrated! -Finishing of the work foreseen for August this year

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 5 out of 24 Jovan Puzović, Belgrade SHINE team Pixels repair -ToF (especially ToF-L) performance decreases with time, too many pixels on ToF-L out of order, repair needed - Currently, 98 pixels on ToF-L don't work, and 24 on ToF-R (our analysis, based on ToF online monitoring program) - Szymon analysis (pp80, more sophisticated) and our new analysis (pp158, 2009) show even worst situation!

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 6 out of 24 Jovan Puzović, Belgrade SHINE team ToF-LR pixel efficiency

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 7 out of 24 Jovan Puzović, Belgrade SHINE team Pixels statistic February 2013, 30 GeV

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 8 out of 24 Jovan Puzović, Belgrade SHINE team Pixels statistic Left side: 81 dead pixels (9.1%)(~70 PMT!) 17 almost dead (1.9%) not working(11.0%) Right side:20 dead pixels (2.2%)(~16 PMT!) 4 almost dead (0.5%) not working(2.7%)

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 9 out of 24 Jovan Puzović, Belgrade SHINE team Cassette inspection

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 10 out of 24 Jovan Puzović, Belgrade SHINE team Broken PMT

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 11 out of 24 Jovan Puzović, Belgrade SHINE team Spare parts We found some spare PMTs with scintilators 6 cm – 1 pcs(needed ~30) 7 cm – 17 pcs(needed ~30) 8 cm – 25 pcs(needed ~30) pcs(needed ~90) Replacing foreseen for middle of August ( )

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 12 out of 24 Jovan Puzović, Belgrade SHINE team New parts -FEU-87 doesn’t produce any more -No leftovers in Dubna! -Replacement: Hammamatsu R3478 from Buda wall (~400 pieces with HV voltage dividers, optical coupled with grease, can be use again) -Smaller then FEU, mechanically can be adapted to fit in existing cassette (photocatode 15mm instead of 22!)

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 13 out of 24 Jovan Puzović, Belgrade SHINE team New parts

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 14 out of 24 Jovan Puzović, Belgrade SHINE team Hammamatsu PMT -Wavelength (Peak): 420nm -Dynode Stages: 8 (FEU-87 11!) -Anode to Cathode Supply Voltage: 1700V -Max Anode to Cathode Voltage: 1800V -Gain Typ.: 1.7 x Rise Time Typ.: 1.3 ns -Assembled with our ToF-LR scintilators an tested (cosmic) -Nominal HV (1700V) too high (gain too high)! Use ~1000V -More current consumption (~30%) compared to FEU-87!

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 15 out of 24 Jovan Puzović, Belgrade SHINE team Hammamatsu PMT

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 16 out of 24 Jovan Puzović, Belgrade SHINE team Hammamatsu PMT

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 17 out of 24 Jovan Puzović, Belgrade SHINE team PMT from the right wall

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 18 out of 24 Jovan Puzović, Belgrade SHINE team PMT from the right wall

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 19 out of 24 Jovan Puzović, Belgrade SHINE team Pulse shape

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 20 out of 24 Jovan Puzović, Belgrade SHINE team Amplitude spectra

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 21 out of 24 Jovan Puzović, Belgrade SHINE team Conclusion -Hammamatsu PMTs performed very well during testing (in spite of their smaller photocatode) -Seems that its possible to produce replacement for broken pixels on the ToF left wall based on Hammamatsu PMTs -However, lots of problems are foreseen!

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 22 out of 24 Jovan Puzović, Belgrade SHINE team Conclusion -A lot of mechanical work needed! - new cassettes have to be produced (12 of them) - new scintilators wanted - electrical cables have to be extended - mechanical support for (smaller) PMTs for tight fit to existing space in cassette - light guides for laser calibration system needed - replacing the old cassette with the new one, then use good FEU-87 pixels as spare part for the rest of the wall - HV calibration needed! - Current consumption?

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 23 out of 24 Jovan Puzović, Belgrade SHINE team Conclusion -Price (in CHF and man power) cannot be estimate at the moment – mostly for traveling expenses and men work! -Further study needed – how to mechanically adapt smaller PMTs to tight fit in existing cassette space? -Cost-benefit analysis needed: what we will get and how much does it cost!

Faculty of Physics, University of Belgrade Collaboration meeting, Dubna, Page 24 out of 24 Jovan Puzović, Belgrade SHINE team Thank you!