To simulates the global FLT decision the CTD and CAL information has been used. A parameterisation of the CTD FLT was made [7]. A track consistent with coming from the bunch-crossing point in the z-direction as would be determined by the CTD FLT sets the CTD-FLT decision to TRUE. Energy sums in the calorimeters were made and if the total scalar energy sum was above 10 GeV the CAL-FLT decision was set to TRUE. A logical AND was made between these two decisions and if TRUE the event was considered to have passed the global FLT and available to the SLT. Using this parameterisation, we accepted 99% of the NC events, 93% of the CC events, and 6 kHz worth of BG background [2, 7, 8]. Not much more than a factor of two in reduction for the BG rate can be achieved by using slightly different calorimeter global energy sums [8, 9, 10].
The CTD hit, digitisation, and track truth were converted to BOS banks and written to disk. The events could then be displayed using the CTD-DISPLAY program or analysed using the offline reconstruction harness.