Source is 14.92 cm away from the left PMT
Source is 35.56 cm away from the left PMT
Source is 55.88 cm away from the left PMT
Source is 76.52cm away from the left PMT
Source is 87 cm away from the left PMT
Calibration curve
The slope is 0.1381 ns/cm or 7.24 cm/ns.