Pion Interferometry Using Wavepackets *

Originally the interferometric method of Hanburry Brown, Twiss (HBT) was developed in astronomy and used to determine the angular radii of stars [1]. Shortly afterwards it was recognized that a similar procedure can also be applied to pions emitted in high energy reactions to measure the size of the pion emitting source [2]. However, it is clear that the different conditions prevailing in high-energy or heavy-ion reactions ask for certain modifications of the original formalism. The table 1 lists the relevant parameters encountered in the study of stars or hot nuclear matter. The correlation areas ∆Ω are given by the solid angle necessary to