Dear Marcel,

It is nice to be able to say it is a "first observation".
Although this is just our HEP definition of an "observation".

I did not spend much time on reading and I have only one remark:

Line 148;
Here t_i is defined as the average decay time value in bin i.
And I read that as t_i = Sum(j=1,Ni) (tij)/Ni, with Ni the
number of events in bin i.
Should it not be t_i = exp( Sum(j=1,Ni) (ln(tij)/Ni) )?

At large t/tau we take large bins and the difference between the
to two ways to determine t_i will largest.
With the second definition the values of t_i will be smaller and
the quadratic term with (x')^2 will be more positive.
Therefore, I expect the negative (x')^2 to be closer to zero.
With the present uncertainty this is not a shocking comment.

As the statistics in WS is less than in RS, we should determine
t_i from WS only and make sure we have a corresponding sample of RS 
that has the same t_i.
It is not stated in line 148 of what events the average t is taken.

Best regards,
  Tjeerd