beam with laser

Reconstruction performance of the beam data with calibration laser.

  • CERN 18
  • bar with 3-layer spherical lens attached to the edge of the prism
  • p/pi @ 7 GeV/c; 25 degree polar angle
  • geometrical and TI reconstruction
  • delta t selection with s = 0.5 ns
  • with beam direction correction
  • with per-PMT Cherenkov angle correction

Hit patter and propagation time for configuration with (top) and without (bottom) calibration laser:

Blue and red lines show propagation time without and with calibration laser, respectively.

Beam data with calibration laser in comparison to simulation as the function of laser intensity. X axis shows laser intensity in 100 ns window.

Time imaging:

Trigger rates (GPIO 1 trigger 1 = ch 512; GPIO 2 trigger 2 = ch 513; GPIO6 Trigger box (LEVCON, NIM out) TRG cable from Trg1 (can be changed) or Laser cable (since 1.8.2018) = 517; GPIO 9 Trigger box (LEVCON, LVDS out) TRG cable from Trg1 (can be changed)) = ch 520. PiLas intensity 15.0% :

PiLas intensity 13.2% :