15 December 2015Alan Norton, NA62, LKR WG 1 LKR Calibration Topics for 2016 Pedestals Pulser Calibration Bad Channels Time Calibration Small Pulses LKR Calibration Topics for 2016 Pedestals Pulser Calibration Bad Channels Time Calibration Small Pulses Alan Norton / Ferrara

15 December 2015Alan Norton, NA62, LKR WG 2  Continue to monitor bad pulses from Transceiver Power Supplies. There is a clear improvement with repairs, which should be completed for the 2016 run.  Channel gains are very stable (no signs of the frequent gain jumps seen in the past with CPDs).  Pedestals must be better monitored. Baseline Equalisation degrades with time (glitches, firmware resets, … ). Wandering pedestals directly impact cluster energy biases and resolution.  In 2016, random NZS pedestals, and pulser calibrations, should be recorded during data taking (as in the past), and streamed for fast analysis (best online and automatic).  Give more priority to the transition from old to new software, with storage of run-dependent constants in the NA62 DB. Next Actions (from October 2015)

15 December 2015Alan Norton, NA62, LKR WG 3 TOO UNSTABLE in 2015 : ( Baseline Equalisation not robust enough) Cream firmware? Random hiccups? Temperature variation? ….. NEED routine procedures to monitor and record history On-line, (semi)-automatic Regular NZS events with random trigger Early detection of problem channels or Creams Unless Baseline Equalisation improves: NEED run-dependent peds in reconstruction Only one set in 2015! Make available fast for online and offline PEDESTALS

15 December 2015Alan Norton, NA62, LKR WG 4 GAINS Stable in 2015 but : Need to check for unexpected behaviour e.g. bad pulses seen at high energy (TX PS) NEED routine procedures to monitor and record history On-line, (semi)-automatic Regular samples with calibration trigger.. end of each burst or dedicated runs Early detection of problem channels or Creams Add histograms to the online monitor PULSER CALIBRATION

15 December 2015Alan Norton, NA62, LKR WG 5 NEED to monitor, and store history : Fixed list, e.g. dead preamps Dynamic list from pedestal & Pulser runs Occasional bad Creams NEED UP-TO-DATE run-dependent lists for: On-line reconstruction Offline reconstruction and MC Analysis Easy visual inspection NEED to be consistent: Fix different lists e.g. from Alan and Michal Avoid ad hoc lists in reconstruction BAD CHANNELS

15 December 2015Alan Norton, NA62, LKR WG 6 T 0 s for 2015 were extracted by Riccardo : Using physics triggers (  +  0 ?) Limited statistics, especially on boundaries Resolution about 700 ps (?) - should it not be better? (my question) - is there any energy dependence of the T 0 ’s ? STUDY if calibration pulser can help (started by Alan) More promising with Creams, but … different cable lengths in the pulse distribution Small differences in pulse shape TIME CALIBRATION

15 December 2015Alan Norton, NA62, LKR WG 7 Suggested further study with a mixture of physics and calibration data Issues with present ZS - single pulse level in Creams Non-uniform / biased pulse suppression because of noise variation across the LKR (X-dependence) Cutting power reduced by noise with the present algorithm (cut on max-min in 8 samples) No halo expansion biases cluster energies in a complicated way, and reduces resolution; clusters may be split Is there scope for more elaborate Cream algorithms? Can we go back to precise pedestals with extra logic for pile-up? Can we envisage two-level ZS: Cream + online PCs? Have we given up on no-loss bit compression? Digital Filtering limitations and possible improvements Energy (non-)linearity SMALL PULSES

15 December 2015Alan Norton, NA62, LKR WG 8  2015 was about SURVIVAL during hectic evolution with many other priorities  2016 should be about moving to ROUTINE (semi-)automatic procedures  Time-dependent calibration data sets are needed, accessible at all levels. Ad hoc data bases are not sustainable.  There is need for more cross-talk between Basic Calibration (single channels) and Reconstruction (clusters).  In 2015, there was limited effort for Basic Calibration : Riccardo:indispensable, but everywhere Michal:other responsibilities; focusing on Analysis Alan:part-time; a reluctant novice with NA62 software Some Comments