Background investigations

The EToF PID plots show an unexpected high Background:

which is not sufficiently described by a high order polynomial: 

Reflections

Signal-Reflections, likely from the edge of the Read-out-strips, can be "absorbed" by the original Signal, resulting in an artificially prolonged Time-over-Threshold value for the corresponding Digi. This might have an impact on the ToT & Walk-Calibration and Position and Timing of reconstructed Hits.

Sketch of the Signal/Reflection pathways on a single strip

ToT - Correlation: left vs. right Side of Strip (USTC Counter)

ToT vs. Y-Position  (USTC Counter)

delta Y (Intersections - Hits): Data vs. Simulation

Data (Red) : System Resolution < 80 ps

Simulation (Blue) : Counter Resolution 50ps, Electronics Resolution 25ps, no Noise

Simulation (Blue) : Counter Resolution 60ps, Electronics Resolution 60ps, no Noise

Simulation (Blue) : Counter Resolution 60ps, Electronics Resolution 60ps, 1 to 5 Noise Hits per Counter & Event

local Y-Position shift

Local Y of Hits reconstructed from Data shifted towards the center of the counter (Y=0)

No shift observed in Simulation:

 
 -> might be related to Calibration ?