1. Background at LCcal Panic limit: 1% occupancy in the detector Si detectors excluded from evaluation. Assumed: 10000x3 Sc. Channels Guessed values: muons: 6/BX inside the detector (with the pessimistic assumption that a crosses the whole detector) hadrons from minijets: 100xEmip= 25 GeV/BX (also for n) Photons: N<100x Emip/Eγ~10000 (for Eγ=2.5 MeV) Rad Bhabhas: 10/BX.

3. Background at Shashlik Panic limit: 1% occupancy in the detector TDR: 44000 channels Guessed values: muons: 3.4/BX inside the detector (with the pessimistic assumption that a crosses the whole detector: >100 hits) hadrons from minijets: 400xEmip= 100 GeV/BX Photons: N<400x Emip/Eγ~40000 (for Eγ=2.5 MeV) Rad Bhabhas: 10/BX.