The Power Law input flux distribution is another useful case present in
the UVES ETC.
In this case the input flux distribution
is defined as:

(2.4)

where
is the wavelength at which the flux is detected,
is the reference wavelength of the power law,
i is the power law index number, in general a real number,
and the reference flux F_{0} is given by the
(eq. 2.5).