# Field Off Studies 2

Looking at Run st_physics_22228005_raw. In Sequence and hit finding T0=6, m_thresh_lo = 5+mPedOffSet; m_thresh_hi = 15+mPedOffSet; m_n_seq_lo = 2; m_n_seq_hi = 0; m_inv_prod_lo = 8. Common mode noise subtraction is done via the first 2 anodes, the RMS of the noise is assumed to be 2.1. The T0 assumption is known to be wrong and should be at -4. The drift velocity is taken as 0.7E6
Fig. 1 shows the correlation between the number of hits found with flag < 4 (i.e. good) and the number of tracks found in the TPC. There is a nice strong liniear correlation (good).

Fig 3.
Events are considered if the -20cm .lt. primary vertex z .lt. 20. Only primary tracks are considered if they have a flag .gt. 0. Hits are considered if they have a flag < 4

Helen Caines
Last modified: Tue Aug 21 12:18:31 EDT 2001