  The purpose of the present article is to offer an analytical model that can
be used for the calibration of photomultiplier tubes (PMTs). The derivation of
the mathematical formulae is discussed extensively and we apply this machinery
to a real problem; the gain determination of the R7081 Hamamatsu PMT. We hope
that our work can provide a third, powerful alternative to the task of gain
deconvolution. We also believe that the techniques explained in this article
can be applied to other problems in PMT calibration and monitoring.
