ABSTRACT

The isotopic composition of the enigmatic xenon component (the so-called Renazzo-type fission xenon, CCF or X), which is said to be released from carbonaceous chondrites at temperatures 600 to 1, 000°C, is explained in terms of the variation of the isotopic ratios due to a combined effect of massfractionation, neutron capture and cosmic-ray irradiation processes, which took place during the early history of the solar system.