# The Kramers-Kronig Toolbox (KKTOOL)

## V. Ossenkopf,

MPG AG ``Dust in Star-Forming Regions'' Jena

The Kramers-Kronig toolbox (KKTOOL) is an interactive
program for manipulating optical constants/dielectric functions of
different materials. At any given step the Kramers-Kronig consistency
of the materials can be checked or reproduced. Starting from an
arbitrary set of constants (*n*, *k*, *epsilon'*, or *epsilon''*)
the other functions may be produced by a Kramers-Kronig analysis.
A convenient extrapolation of the constants outside of the range
covered by the material data has to be done by the user. Several
standard functions for the extrapolations are available and the
continuation can be visually controlled. The computed
constants can be stored or used in further calculations. All
computations can be controlled by eye via graphical plots.