TELL1 high rate tests @ Birmingham Karim Massri University of Birmingham karim.massri@cern.ch

1. TELL1 high rate tests @ Birmingham Karim Massri University of Birmingham karim.massri@cern.ch CEDAR WG Meeting – CERN – 26/03/2012

2. Karim Massri – CEDAR WG Meeting – CERN Introduction Experimental setup Special requirements for the random rate (RaR) tests RaR tests: components & TELL1 input Adjusting the setup to get regular rate (ReR) signals Results ReR & RaR results with TDCB clock @ 40 MHz ReR & RaR results with TDCB clock @ 80 MHz Conclusions Outline

3. Karim Massri – CEDAR WG Meeting – CERN High rate tests motivation: Current estimated rate on each PMT of the CEDAR ~ 5 MHz Electronics inefficiency study needed to choose the most suitable number of PMTs Particular remarks: TDCB v5 has been used (previously v2) Single channel study TDCB clock initially @ 40 MHz, then → 80 MHz Introduction Increasing the clock frequency means increasing the speed of the data reading from the TDCB buffer!

4. Karim Massri – CEDAR WG Meeting – CERN Experimental setup

5. Karim Massri – CEDAR WG Meeting – CERN Special requirements for RaR tests on the source: Source of Poissonian-distributed pulses Source must work at high rates (~MHz) Frequency must be adjustable on the data acquisition: The number of input pulses must be known All the pulses must be sent while TELL1 is acquiring Experimental setup

6. Karim Massri – CEDAR WG Meeting – CERN RaR tests: components Experimental setup Same setup of December tests (with TDCB v2) Black Box PMT LED preAmp + NINO Light filter TDC board (v5) 2ch pulse generator Scaler: ORTEC 974 4 channels 100% efficient up to 92 MHz TELL1 TRIGGER Coincidence NIM to TTL converter Attenuator (31 db) CAEN 16ch Low Threshold discriminator

7. Karim Massri – CEDAR WG Meeting – CERN RaR tests: TELL1 input Experimental setup Same setup of December tests (with TDCB v2) Black Box PMT LED preAmp + NINO Light filter TDC board (v5) 2ch pulse generator To the LED: DC voltage with adjustable amplitude → variable frequency! (from 0 up to 50 MHz!) To the NIM modules: 5µs long NIM pulse @100Hz TELL1 TELL1 time window = 20 µs TRIGGER Coincidence NIM to TTL converter Attenuator (31 db) CAEN 16ch Low Threshold discriminator Current firmware can handle no more than 256 words per trigger!

8. Karim Massri – CEDAR WG Meeting – CERN RaR tests: TELL1 input Experimental setup Some more details about the input... NINO input (after the preAmp): Amplitude ~ 120 mV Width ~ 8 ns NB: the signal is extremely regular! (attenuated NIM signal)

9. Karim Massri – CEDAR WG Meeting – CERN ReR tests: adjusting the RaR setup.. Experimental setup LED can't be used to generate ReR because it doesn't respond with a regular light pulse! Black Box PMT LED preAmp + NINO Light filter TDC board (v5) 2ch pulse generator Scaler: ORTEC 974 4 channels 100% efficient up to 92 MHz TELL1 TRIGGER Coincidence NIM to TTL converter Attenuator (31 db) CAEN 16ch Low Threshold discriminator

10. Karim Massri – CEDAR WG Meeting – CERN ReR tests: TELL1 input Experimental setup Black Box PMT LED preAmp + NINO Light filter TDC board (v5) 2ch pulse generator To the Low Th Discriminator: Amplitude: 25 mV Width ~5 ns variable frequency (0¸200 MHz) To the NIM modules: 5µs long NIM pulse @100Hz TELL1 TELL1 time window = 20 µs TRIGGER Coincidence NIM to TTL converter Attenuator (31 db) CAEN 16ch Low Threshold discriminator Current firmware can handle no more than 256 words per trigger!

11. Karim Massri – CEDAR WG Meeting – CERN Upgrading @ 80 MHz.. Current TELL1 firmware version: v132 (from Pisa) Current TDCB firmware version: v5 (from Pisa) TELL1 firmware @ 80 MHz: v136 (from S.Venditti) TDCB firmware @ 80 MHz: v6 (from S.Venditti) TDCB firmware upgrade via JAM (thanks to B.Angelucci!) Experimental setup

12. Karim Massri – CEDAR WG Meeting – CERN Data taking procedure Set the frequency (RaR: adjusting the LED voltage) Enable the scaler, start TELL1 acquisition Turn on the trigger pulse from the generator Wait until a certain number of counts has been reached Turn off the trigger pulse Stop scaler, end TELL1 acquisition Experimental setup 17 + 24 (RaR + ReR) runs / clock frequency (40MHz or 80MHz) each one for a different frequency (~1MHz to ~15 MHz) ~20000 pulses have been sent to the TELL1 during each run

13. Karim Massri – CEDAR WG Meeting – CERN Results

14. Karim Massri – CEDAR WG Meeting – CERN ReR tests @ 40MHz: inefficiency TELL1 high rate tests TDCB v2 (December tests) VS TDCB v5 Trailing losses due to extra leadings No more event losses @ ~ 5 MHz Up to 11 MHz NO leading losses!

15. Karim Massri – CEDAR WG Meeting – CERN RaR tests: TELL1 output TELL1 high rate tests Leading-to-leading Δt distribution measured by the TELL1 NO leading losses up to 11 MHz →Fit with exponential for t>100ns → Mean frequency measured from slope

16. Karim Massri – CEDAR WG Meeting – CERN RaR tests @ 40MHz: inefficiency TELL1 high rate tests TDCB v2 (December tests) VS TDCB v5 v5 looks slightly better!

17. Karim Massri – CEDAR WG Meeting – CERN ReR tests @ 80MHz: inefficiency TELL1 high rate tests TDCB v5 @ 40 MHz VS TDCB v5 @ 80 MHz ~ same inefficiency at double rate!

18. Karim Massri – CEDAR WG Meeting – CERN RaR tests @ 80MHz: inefficiency TELL1 high rate tests TDCB v5 @ 40 MHz VS TDCB v5 @ 80 MHz ~ same inefficiency at double rate!

19. Karim Massri – CEDAR WG Meeting – CERN RaR tests @ 80MHz: inefficiency TELL1 high rate tests TDCB v5 @ 40 MHz VS TDCB v5 @ 80 MHz ` 4% @ 5MHz (instead of ~16%)

20. Karim Massri – CEDAR WG Meeting – CERN Conclusions TDCB v5 has been set and is now working @ Bham (thanks to B.Angelucci!) TDCB v2 <-> TDCB v5 TDCB v5 results slightly better (@ 40 MHz) TDCB v5 @ 80 MHz (thanks to S.Venditti!) wrt results @ 40 MHz ~ same inefficiency at double rate (as expected) for both ReR and RaR TDCB clock @ 80 MHz looks really promising!