Today's Progress 25. Aug. 2005

Track reconstruction by VDC - again

Since a cable swapping has been found at TKO DrT II rear side(cable 12 and 14), we do need to construct VDCtop analysis properly.

0. Long-term stability of the tracking efficiency for BEAM originated trigger without distinguishing the trigger pattern. The efficiency is about 50 % through the production term. The reason of a jump between run 121 and 122 is unknown at this moment.

Long-term variation of VDC tracking efficiency for beam.

1. Long-term stability of the resolution BEFORE spline correction for COSMIC RAY

Long-term variation of VDC resolution for cosmic ray before spline correction.

2. Long-term stability of the resolution BEFORE spline correction for BEAM

Long-term variation of VDC resolution for beam before spline correction.

3. Long-term stability of the resolution AFTER 1st stage spline correction for COSMIC RAY. The resolution is about 250 and 200 micron for top and bottom, respectively.

Long-term variation of VDC resolution for cosmic-ray after 1st-order spline correction.

4. Long-term stability of the resolution AFTER 2nd stage spline correction for BEAM. They are fairly stable at ~300(top) and ~250(bottom) micron.

Long-term variation of VDC resolution for beam after 2nd-order spline correction.