2018 Data - Analysis Page

From Xem2
Jump to navigationJump to search

2018 Data: Analysis Summary

Target Information

  • Target configuration report
    • Note: cryotargets need to subtract window thickness and apply a correction of 0.996 due to length contraction at low temperature
  • Target ladder survey
    • Note: z position of "raster target" is upstream face. All solid targets have upstream face at same psoition.
  • Solid target notes
    • Note: I think there was a transcription error for the carbon target. The report says 0.5244 g/cm2. I get 0.5224 g/cm2 from the notes above.
  • Beam and target offsets:
    • Analysis of SHMS/HMS C data (log entry needed)
    • Offsets to put in MC (from email from Abishek)
      • x-spec offset = -0.127 cm (updated from + to - 5/21/2021)
      • y-spec offset = -0.057 cm
      • x-beam offset = (0.073 - x-bpm) cm (xbpm calculated in right handed coordinate system)
      • z-target offset = 0.212 cm (carbon target)
        • LH2 1.55 mm upstream of carbon center: z = 0.057
        • LD2 1.45 mm upstream of carbon center: z = 0.067
        • Be 2.4 mm downstream of carbon center: z = 0.452
        • 10B4C and 11B4C at same z position as carbon: z = 0.212
  • How I get Boron from B4C: [1]

SHMS/HMS Cherenkov Gas Information

  • CO2 at 1 atm was the gas used in the SHMS noble gas Cherenkov.

https://logbooks.jlab.org/entry/3508688

  • The HMS Cherenkov was filled with C4F8O at 0.45 atm.

https://logbooks.jlab.org/entry/3497989

BCM calibration

  • Summary from Deb
  • Correction for runs 2557-2563 (multiply charge by 1.0115) XEM2 elog 60

Efficiencies and corrections

Radiative corrections