TELL1 high rate Birmingham Karim Massri University of Birmingham CEDAR WG Meeting – CERN – 26/03/2012

Karim Massri – CEDAR WG Meeting – CERN 26/03/ 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 40 MHz  ReR & RaR results with TDCB 80 MHz Conclusions Outline

Karim Massri – CEDAR WG Meeting – CERN 26/03/ 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 40 MHz, then → 80 MHz Introduction Increasing the clock frequency means increasing the speed of the data reading from the TDCB buffer!

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

Karim Massri – CEDAR WG Meeting – CERN 26/03/ 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

Karim Massri – CEDAR WG Meeting – CERN 26/03/ RaR tests: components Scaler: ORTEC 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)

Karim Massri – CEDAR WG Meeting – CERN 26/03/ 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 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)

Karim Massri – CEDAR WG Meeting – CERN 26/03/ 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

Karim Massri – CEDAR WG Meeting – CERN 26/03/ ReR tests: adjusting the RaR setup.. Scaler: ORTEC 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)

Karim Massri – CEDAR WG Meeting – CERN 26/03/ ch 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 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)

Karim Massri – CEDAR WG Meeting – CERN 26/03/ MHz.. Experimental setup Current TELL1 firmware version: v132 (from Pisa) Current TDCB firmware version: v5 (from Pisa) TELL1 80 MHz: v136 (from S.Venditti) TDCB 80 MHz: v6 (from S.Venditti) TDCB firmware upgrade via JAM (thanks to B.Angelucci!)

Karim Massri – CEDAR WG Meeting – CERN 26/03/ 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 (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

Karim Massri – CEDAR WG Meeting – CERN 26/03/ Results

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

Karim Massri – CEDAR WG Meeting – CERN 26/03/ 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

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

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

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

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

Karim Massri – CEDAR WG Meeting – CERN 26/03/ Conclusions TDCB v5 has been set and is now Bham (thanks to B.Angelucci!) TDCB v2 TDCB v5 TDCB v5 results slightly better 40 MHz) TDCB 80 MHz (thanks to S.Venditti!) wrt 40 MHz ~ same inefficiency at double rate (as expected) for both ReR and RaR TDCB 80 MHz looks really promising!