Effect of the bar box window between radiator bars and lenses on performance.
- DIRC@EIC, ePIC, standalone simulation
- 3-layer spherical lens with sapphire, r=[62,36]
- 3 mm pixels HIQ400, CE=95%
- pi/K @ 6 GeV/c
- 0.5 mrad track smearing at tracking layer
- phi = 0 (no field); vertex y-shifted by 0.5*barwidth (to hit middle of the bar)
- 0.1 ns time precision
- transport efficiency fitted to BaBar data
- geometrical reconstruction with averaged LUT from 15M photons
- GR with per-PMT and chromatic corrections
- 20k tracks for pdf generation (per each particle species) (generated with 0.5 mrad track resolution); 5k for determining separation
Comparison for a window with 25 mm height, 350 mm width and different thickness (1,2,4 mm). Event display for 2 mm thick window (30 deg polar angle), side view:
Top view (shows photons leaking through sides):
4 mm thick window. Side view:
Top view:
Performance plots. Photon yield after GR:
Photon yield after TI:
SPR:
GR:
TI:
8 mm thick window with black sides. Side view:
Performance plots for window with back sides. Photon yield after GR:
Photon yield after TI:
SPR:
GR:
TI:
New. 5 mm thick window placed after lens. Attached directly without gaps. Event display with photons from one 6 GeV/c pion at 90 degree polar angle:
5 mm thick window placed after lens. With 0.1 mm air gaps on both sides:
5 mm thick window placed after lens. With 3 mm optical cookies on both sides:
Performance for 6 GeV/c pi/K. Photon yield after TI:
GR:
TI:
