Follow-up to discussion July 24, 2012 discussion on BCAL timing

This is a follow-up to the discussion on BCAL Simulation at the Jul 24, 2012 Readout meeting. Specifically, there was some question on the time walk plot shown in David L.'s slides. There was concern that the time difference between 20 degrees and 30 degrees for the downstream end varied significantly from the upstream end.

Thinking more about this, the difference arises from the difference in the time of flight to the point of impact for the two different angles. The calculation can be seen below for those interested. A revised plot with lines indicating the calculated times for each of the signals at the SiPM is shown here:

(Please ignore the comment in the lower right about "arising from TOF". That was left over before a sign error was identified.)