I presented at the Tuesday Centrality meeting (10/5/21) that <refMult> vs. ZdcCoincidenceRate had a positive slope. We expect luminosity dependence to have a negative slope. It was speculated that the strange luminosity dependence was due to pileup that was not rejected by our pileup removal procedure. A way to test this was to plot <nBTofMatched> vs. ZdcCoincidenceRate. As you can see below, <nBTofMatched> also shows a positive correlation with ZdcCoincidenceRate. The slope is m=0.00175 +/- 0.00003. The slope of <refMult> vs ZdcCoincidenceRate was m=0.0014 +/- 0.0001.

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