Data Processing Model
All raw data permanently saved; only one reconstruction pass on full sample (resource limited).
Efficient selective access back to the raw data required for diagnostics, systematics and calibration studies, etc.
Raw data reconstruction yields event summary data, ‘DSTs’; 14.4M ev/yr.
DST is input to analysis-specific ?DST production with improved and optimized algorithms, better calibrations etc. ?DSTs typically up to 2TB
Several ?DST production passes required in the course of a physics analysis as algorithms and selections are refined. Development proceeds at institutes, with small samples; production at RCF.
Development work requires good access to DST, RAW data from ?DST level: minimal remote-access penalty, and access as transparent as possible to minimize book-keeping load.
Physics summary for physicist’s desktop analysis is typically a further distillation of the ?DST down to O(1-100GB), usable at home institute