Muon Recording Studies and Progress for the MICE Tracker Tracker Data Readout Basics Progress in Increasing Fraction of Muons Tracker Can Record Determination of Recordable Muons as Functions of Digitization Time and Buffer Level Plans and Outlook

Tracker Data Readout Basics 16 Analog Front End II t (AFE-IIt) boards (‘t’ stands for time) Input: Analog charge signals from 512 channels Output: - Digital hit pattern of 512 channels - 512 charge amplitudes - 512 time amplitudes Each board contains sixteen 32-channel Trigger and Pipeline (TriP-t) chips. Data from all 16 chips processed in parallel Within each chip, 32 channels processed in series DFPGA X 4 … AFPGA AFPGA X 4 … X 4 … ADC ADC ADC ADC TriP-t TriP-t TriP-t TriP-t X 4 … Data from VLPCs 1/4 of AFE-IIt board

Muon Recording Increase number of recorded muons by With D0 configuration and 600 kHz muon rate, AFE-IIt boards can record about 136 kHz Increase number of recorded muons by Decreasing digitization time Zero suppression Have TriP-t pipeline collect data during digitization Remove unnecessary setup cycles Implementing TriP-t analog buffer Digitization time ≠ dead time.

Muon Recording Digitization of analog charge and time data limits the fraction of muons the tracker will record. Primary efforts in tracker firmware development have been to reduce time to digitize 32 channels of each TriP-t chip through zero suppression. Have performed a detailed study of how many muons the tracker can record.

Reducing Digitization Time Assumed muon rate is 600 kHz for average time between muons of 1667 ns. Clock period taken as 18 ns Assume 2 out of 32 channels of TriP-t have charge data above threshold ~ 5724 ns: D0 implementation ~ 5670 ns: Adjust for shorter ISIS bucket period 4536 ns: TriP-t pipeline collect data during digitization 2376 ns: Zero-suppress 30 of 32 TriP-t channels 1836 ns: Reduce zero-suppression time from 2 to 1 cycle. 1566 ns: Remove cycles from set-up processes. We are now starting to reduce the dead time so that it’s comparable to the average time between muons.

Implementing Buffer x x x x TriP-t chips have 4-level analog buffers which have not been implemented nor tested. Using one level of buffer greatly increases fraction of muons recorded. Example: x x x 1 2 3 4 5 6 7 4 of 7 muons recorded No Buffer 1 3 4 7 x 1 2 3 4 5 6 7 6 of 7 muons recorded 1-level Buffer 1 2 3 4 5 7

600 kHz Muon Rate 4-level Buffering 3-level Buffering No Buffering (Digitization Time)-1 = 600 kHz 1000 2000 3000 4000 0.2 0.4 0.6 0.8 1.0 Fraction of Recorded Muons Digitization Time (ns)

Where we were. 600 kHz Muon Rate (Digitization time ~ 5600 ns) 4-level Buffering 3-level Buffering 2-level Buffering 600 kHz Muon Rate 1-level Buffering No Buffering (Digitization Time)-1 = 600 kHz 1000 2000 3000 4000 0.2 0.4 0.6 0.8 1.0 Fraction of Recorded Muons Where we were. (Digitization time ~ 5600 ns) Digitization Time (ns)

Where we are. 600 kHz Muon Rate 4-level Buffering 3-level Buffering No Buffering (Digitization Time)-1 = 600 kHz 1000 2000 3000 4000 0.2 0.4 0.6 0.8 1.0 Where we are. Fraction of Recorded Muons Digitization Time (ns)

Where we’d like to be. 600 kHz Muon Rate 4-level Buffering No Buffering (Digitization Time)-1 = 600 kHz 1000 2000 3000 4000 0.2 0.4 0.6 0.8 1.0 Where we’d like to be. Fraction of Recorded Muons Digitization Time (ns)

Plans and Outlook Test digitization, buffering, and firmware with TriP-t chips and AFE-IIt boards. More about this in next talk…