EM background rate studies

Data sample:

• beam photons (no interactions inside the cave)
• collimator cave background (photon beam hallo, particles from the cave, ...)

Subdetector rates (at least one hit in the subdetector)

             Beam background               Cave Background

• TOF 35.9 MHz 36.8 kHz

• Start counter 1.86 MHz 1.67 kHz

• FCAL (Ecell > 30 MeV) 4.25 MHz 6.69 kHz

• BCAL (Ecell > 20 MeV) 300 kHz 1+-1 kHz

Fig. 1. FDC rate

Fig. 2. FDC rate and occupancy.

Fig. 3. CDC rate.

Fig. 3. FCAL rate.