Lithium isotopic composition in some stone meteorites

The isotopic composition of lithium has been determined in two achondrites and seven chondrites (including two carbonaceous chondrites). No significant variations in the 7 Li/ 6 Li at the 1% level were found. Our results set upper limits of 1 × 10 19 or 3 × 10 20 protons/cm 2 with E p > 5MeV, depending on the model, for the excess irradiations possibly suffered by these meteorites (including Allende) compared to earth.