Angelika provided some rough luminosity figures for the fills containing the vernier scans:

10207   0.3
10276   1.8
10399   2.60
10415   2.80
10507   5.2
10536   3.5

units are 10^31 cm^-2 s^-1.

I believe, after talking with Jan, that these are the head-on beam values, and not an average.  That's unfortunate, because if they were the average I could use them to determine the cross section of BHT3, and hence the BHT3 luminosity in any other run, just from the total BHT3 triggers on the runlog browser.

I have asked for the appropriate chain options to produce the vernier scan runs so that I can count the BHT3 events.  In the meantime, very roughly, the BHT3 rate at the peak seems to be ~20Hz

dN/dt=sigma*L ===> sigma_BHT3=dN/dt / L

sigma_BHT3=20Hz / 3.5*10^31 cm^-2 s^-1

sigma_BHT3=5.7*10^-31 cm^2

sigma_BHT3=0.6 ub as a very rough estimate (the luminosity is a rough estimate by Angelika, the BHT3 rate is a rough estimate by me, and the cross section doesn't correct for hot towers or dead parts of the barrel that may be live in other runs)

From the L2 plots ( http://online.star.bnl.gov/L2algo/l2btowCal/l2btowCal10103044.pdf  ), there is one tower that might be considered hot, firing ~10 times as often as the other towers.  We could use the BHT3/BBC ratio to see if the behavior of the tower is stable from run to run.