KLF beamline meeting - November 21, 2024

Agenda

• Announcements

• FLUKA simulations with 20% CPS radiator (Pavel)

• GEANT4 simulations (Richard)

  • Study with a shielded beam pipe
  • Study with a shield wall

• W-plug temperature estimates for 20% radiator (Hovanes)

• Any other business

Minutes

Present: Vitaly, Eugene, Moskov, Hovanes, Pavel, Alex, Beni, Lubomir, Marshall, Richard, Sashi, Edy, Mikhail

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• Pavel simulated KLF beam using 20% CPS radiator. He uses 6cm OD beam pipe after KPT, but he used 4cm OD beampipe at the cryo-target. Pavel emphasized the importance of controlling the beam size of the diverging beam of CPS that contains particles other than kaons.

• The beam spot at the KPT is wider, still fits in 6cm reasonably well. K-long rate at the cryo-target is consistent with factor of two increase. Statistics is still low due to CPU unavailability last week.

• Eugene asked about radiation backsplash in front of CPS. Pavel says that neutron backsplash increased. Pavel expects that the temperature in the CPS will decrease. The magnet coil dose rate increased by about factor of four.

• Pavel is already running higher statistics and also the low thresholds simulations.

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• Richard made the plots from GEANT4 simulations that allow us to compare the FDC and TOF rates for individual channels between KLF with 14cm W-plug and GlueX-II.

• FDC rates per wire near the beam for KLF with 14cm tungsten plug are very close to what GlueX-II give with the same GEANT4 code.

• Lubomir pointed out that with these rates the occupancies for these wires would be higher than 50%. Most likely, the thresholds for FDC in GEANT4 do not match the thresholds in reality. Lubomir thinks that FDC should be OK with 14cm tungsten plug.