The second page shows the number of 3- and 4-hit stubs, and the distance of closest approach to the beamline of the stub projection; upper right for 3-hit stubs and lower left for 4-hit stubs. In the lower right you find the distribution of the reconstructed z for the stub. I don't know why it is sometimes 0. The spike at just under 600 is the center of the chamber--the default if there was no good reconstruction of Z for any hit. The tall spike is the rear of the chamber, where we get toasted.
The third page shows the numbers of 3- and 4-hit stubs when the abs(z) is greater than 750 cm (the rear of the chamber) at the upper left, and the upper right shows the same when the z is forward of the hot rear. Notice that 3- and 4-hit stubs are found pretty equally in the rear, but at a ratio of 3 to 1 in the rest of the chamber. The bottom plots show the abs(z) when the number of hits is 3 (left) and 4 (right)--no surprises.
The last page shows the chi-squared again when the stub in entirely in a single stack (self=0; upper left) and crossing two stacks (self=1; upper right). The lower left shows the self attribute when the number of hits is 3, and the lower right when the number of stubs is 4.
The second page shows the abs(z) distributions, and below that shows that the west to east ratio doesn't change when you require rear hits (left) or non-rear (right).
Modified 25-Sep-2002 at 14:37
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