Proton Calorimetry/Meetings/2021/07/02

Minutes for UCL Proton Calorimetry Meetings, 2nd July

Present

Simon Jolly, Saad Shaikh, Fern Pannell

Saad Shaikh

• Painted 4 scintillator sheet pairs:
  • Sheets 48 & 23 with primer – one layer to glue pair.
  • Sheets 54 & 1 with appliance – one layer to glue pair.
  • Sheets 52 & 11 with appliance and then primer to glue pair – 10-15 mins for appliance layer to dry.
  • Sheets 53 & 2 with appliance and then primer to glue pair – 30-40 mins for appliance layer to dry.
• Neither combination gives acceptable results: lots of gaps in paint layer due to either inconsistencies in sheet thickness, placement misalignment or paint reaction.
  • Placement of sheets when glueing is difficult: not much room to adjust once placed as this ruins paint layer.
  • Painted pairs will be stripped of paint again.
• Will paint 32 sheets for beam test with single coat of primer to be ready for beam tests.
• New fitting routine using Gauss–Legendre algorithm and Fumili minimiser implemented into photodiode scripts.
  • New routine gives reasonable results where default options either fail or give strange fit results.
  • With a given set of fit results, Gauss–Legendre draws Bortfeld curve slightly differently compared to default Adaptive Singular algorithm.
  • Might require some optimisation of numerical parameters to correct this. Will investigate, but might be that "slow, accurate, non-live" fit uses slower Adaptive Singular algorithm to draw curves.
• Organised new inventory and beam test equipment into new DeWalt tower – tower kept in D109.
• Installed Argon One V2 case on Raspberry Pi.
• FTDI script uses 30-35% of CPU, probably maxing out 1 processor core. Performance issues likely due to lack of power.
• Adding "-O3" optimisation flag when compiling FTDI script gives significant performance improvements on both Pi and Mac.
  • With 4 modules, Mac now gives average time per read of 172us rather than 188us, with an integration time of 170us.
  • With 2 modules, Pi down to 200us from 750us. Still observe some freezes during acquisitions, but far fewer than before.
  • Also observe improvement in frame rate of replay script with this flag. Fitting and plotting scripts are largely the same.
• Will install ROOT on Pi and compile fitting and plotting scripts.