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    User name R. Michaels

    Log entry time 17:54:57 on April25,2007

    Entry number 200027

    keyword=stability of timing offset T0

    There was some concern that the timing is shifted when we
    run at very high Qsq, leading to shifts in coinc. time D.ctimel.
    The most straightforward diagnostic is the T0 of the VDCs.
    See fig 1. I plot one of the chamber raw TDCs for a recent
    cosmics run and for a Qsq=29 He-4 run 2645 for T5 and T6.
    Ideally the T0 should be independent of trigger type and of
    kinematics. If not, it's a long explanation. Anyway, there
    might be shifts of order 40 channels (20 nsec) in these plots,
    it's a little hard to tell. Well, at least its not crazy big.
    So this is a variable to watch. I notice all the root files
    have L.vdc.*.rawtime and R.vdc.*.rawtime.

    FIGURE 1