Fig. 1.

Neat FA mixed with meteorite powder was irradiated at 243 K with 170-MeV protons for 3 min. The uniform proton field was bounded 10 × 10 cm² by the collimator system. The averaged linear energy transfer (LET) was 0.57 keV/μm, and the calculated absorbed dose was 6 Gy. Eleven meteorites classified into the iron (Canyon Diablo and Campo del Cielo), stony-iron (NWA 4482), chondrite (NWA 2828, Gold Basin, Dhofar 959, Orgueil, NWA 1465, and Chelyabinsk), and achondrite (NWA 5357 and Al Haggounia 001) families were used in the FA irradiations. The products were analyzed by gas chromatography–mass spectrometry (GC-MS) after formation of the corresponding trimethylsilyl ethers (TMS).