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 26/03/2012 2 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 26/03/2012 3 High rate tests motivation: C urrent 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 26/03/2012 4 Experimental setup

5. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 5 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 26/03/2012 6 RaR tests: components Scaler: ORTEC 974 4 channels 100% efficient up to 92 MHz LED PMT Light filter Coincidence Black Box TRIGGER TELL1 preAmp + NINO NIM to TTL converter CAEN 16ch Low Threshold discriminator 2ch pulse generator Attenuator (31 db) Experimental setup Same setup of December tests (with TDCB v2) TDC board (v5)

7. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 7 RaR tests: TELL1 input Attenuator (31 db) 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 LED PMT Light filter Coincidence CAEN 16ch Low Threshold discriminator NIM to TTL converter Black Box TRIGGER TELL1 preAmp + NINO TELL1 time window = 20 µs Current firmware can handle no more than 256 words per trigger! Experimental setup TDC board (v5) Same setup of December tests (with TDCB v2)

8. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 8 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) Experimental setup RaR tests: TELL1 input

9. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 9 ReR tests: adjusting the RaR setup.. Scaler: ORTEC 974 4 channels 100% efficient up to 92 MHz LED PMT Light filter Coincidence Black Box TRIGGER TELL1 preAmp + NINO NIM to TTL converter CAEN 16ch Low Threshold discriminator 2ch pulse generator Attenuator (31 db) Experimental setup LED can't be used to generate ReR because it doesn't respond with a regular light pulse! TDC board (v5)

10. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 10 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 Attenuator (31 db) LED PMT Light filter Coincidence CAEN 16ch Low Threshold discriminator NIM to TTL converter Black Box TRIGGER TELL1 preAmp + NINO TELL1 time window = 20 µs Current firmware can handle no more than 256 words per trigger! ReR tests: TELL1 input Experimental setup TDC board (v5)

11. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 11 Upgrading @ 80 MHz.. Experimental setup 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!)

12. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 12 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 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 Experimental setup

13. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 13 Results

14. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 14 ReR tests @ 40MHz: inefficiency Trailing losses due to extra leadings TDCB v2 (December tests) VS TDCB v5 TELL1 high rate tests No more event losses @ ~ 5 MHz Up to 11 MHz NO leading losses!

15. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 15 RaR tests: TELL1 output NO leading losses up to 11 MHz →Fit with exponential for t>100ns → Mean frequency measured from slope Leading-to-leading Δ t distribution measured by the TELL1 TELL1 high rate tests

16. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 16 TELL1 high rate tests RaR tests @ 40MHz: inefficiency TDCB v2 (December tests) VS TDCB v5 v5 looks slightly better!

17. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 17 ReR tests @ 80MHz: inefficiency ~ same inefficiency at double rate! TDCB v5 @ 40 MHz VS TDCB v5 @ 80 MHz TELL1 high rate tests

18. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 18 TELL1 high rate tests RaR tests @ 80MHz: inefficiency TDCB v5 @ 40 MHz VS TDCB v5 @ 80 MHz ~ same inefficiency at double rate!

19. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 19 ` TELL1 high rate tests RaR tests @ 80MHz: inefficiency TDCB v5 @ 40 MHz VS TDCB v5 @ 80 MHz 4% @ 5MHz (instead of ~16%)

20. Karim Massri – CEDAR WG Meeting – CERN 26/03/2012 20 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!