Plate Theory and Extensions - The Position of the Points of Inflection > Page 57

          

  

                                              (51)

Substituting for  from equation (51) in equation (50),

                        

Now,        Consequently, the term  and those

higher can be ignored with respect to .

Then,        and                     (52)

Equation (52) shows that the points of inflection occur at 0.6065 of the peak height. It follows that the peak width, at 0.6065 of the peak  height, will be equivalent to two standard deviations (2s) of the Poisson or Gaussian curve.