DIRECT MEASUREMENTS OF TOTAL REACTION CROSS SECTIONS BETWEEN HEAVY IONS FROM 10 TO 100 MeV/amu : PRELIMINARY CONCLUSIONS

After a review of some theoretical formulations of the concept of total reaction cross OR, involving low energy (4 10 MeV/amu) and high energy (> GeV/amu) models, two experimental methods used for direct measurements of q, are presented, namely the "beam attenuation" and the "associated y-rays 4 a detection" nethods. Then a number of experimental results of OR in the Fermi energy range i s given and the data are compared on the one hand with the predictions of the "low energy" BASS model (assuming a classical onedimensional nucleus-nucleus potential interaction), and on the other hand with the predictions of a "high-energy" microscopic calculation performed using the formalism of KAROL (assuming that nuclear reactions are produced by individual nucleon-nucleon interactions). Finally, some experimental and theoretical problems are discussed and general conclusions are tentatively proposed.