We discuss an implementation of parameterization models provided by the GEA
NT4 package for the description of the X-ray transition radiation (XTR) pro
duced by a relativistic charged particle in a multi layered medium. The imp
lementation allows us to calculate the number of XTR photons, their energy
and angular spectra in a number of XTR radiators of practical interest. Com
parison of simulation with experimental data from gaseous detectors is pres
ented. (C) 2000 Elsevier Science B.V. All rights reserved.