After confirming an apparent MIP-position dependency on time, we have now begun to investigate potential causes.  Since we know that luminosity has also varied over time, we attempted to discover some significant correlation between luminosity and MIP position.

Luminosity and time data was taken from the following file, provided by Jim Sowinski: runSumQA_v2.csv.txt.  The time information was obtained from column 8, and the luminosity from column 9 (with the first column numbered as column 1).

As you can see from the following representative graph, there is no obvious correlation between luminosity and MIP position:

This apparently held true over all Eta bins, except Eta bin 1, which could not be reasonably fit with a P1.  The following two graphs show the Chi^2 versus Eta bin for the P0, in Figure 2, and P1, in Figure 3, fits for each MIP Position versus Luminosity graph.  As can be seen from the graphs, there is no apparent difference between the quality of the P0 and P1 fits, which means that the P0 is just as good a fit for MIP Position vs. Luminosity as the P1.

A complete set of all graphs with fits, including the images displayed on this page, can be found here