TOF/T0 Status

	T0 time-delay calibrations:
		Procedure has been developed and implemented.
		Calibration parameters are determined on a sequence by sequence basis.
		Procedure is as follows:
			Determine the relative position of the 300 ns time calibrator peaks and the prompt T0 peaks.
			The time-delay parameters are adjusted for any observed shift in the time calibrator peak.
			This procedure is repeated for each sequence and the calibration data are stored in the DB on a sequence by sequence basis.
		The biggest assumptions made are:
			The relative position between time calibrator and prompt time signals remains fixed (e.g. sensitive to stability of crossing clock).
			The TDC gains remain constant (we can determine the gain by using the time calibrator peak at 260 ns).

Sequence by sequence calibrations. Use information from DV trees.

Sequence by sequence calibrations. Run 10920 (4 examples).

T0 Time-Delay Calibrations. How well does it work?

	We expect to see:
		The centroids of time spectra of the T0 counters to be stable at 17.3 ns for T0N.
	We see:
		An overall shift of about 0.5 ns:
			Shift in crossing clock timing?
		A shift in the relative peak positions:
			Drift in TDC gain?

T0 Time-Delay Calibrations. How well does it work?

TOF Tracking.

	The tracking to the TOF works well.
	The figures shown on the right shows the difference in the position of the extrapolated track along the wall TB and the position of the sensor that recorded a hit.
	The top figure shows tracking in silver data while the bottom figure shows tracking in a dA data.

TOF Tracking.

	The figures shown on the right shows the difference in the position of the extrapolated track along the wall TC and the position of the sensor that recorded a hit.
	The top figure shows tracking in silver data while the bottom figure shows tracking in a dA data.

TOF Tracking. How well does it work?

	The difference in hit position of the tracks on TB is centered at 0.06 cm with a width of ±1.4 cm (±2 scintillators).
	The difference in hit position of the tracks on TC is centered at 0.7 cm with a width of ±1.2 cm (±1.5 scintillators).
	Need to look at field-off data to verify position of TOF walls.

Summary

	Time-delay calibrations require not a simple overall shift.
	We need to address the need to apply gain corrections too.
	The T0 can in principle be calibrated directly based on the prompt peak, as was done in PR01, but for the TOF we do not have a choice but to use the time calibrator procedure.
	Tracking works fine, and background does not appear to be an issue.
	We are currently producing required DSTs for our TOF studies.