Outstanding Problems of Presolar Diamond in Meteorites
نویسنده
چکیده
Diamond is the first mineral type of presolar grains that were isolated from meteorites, yet it is one of the least understood presolar grain types. An isotopically anomalous component Xe-HL is carried by diamond and is characterized by excesses in both the light, p-process only isotopes (124 and 126) and the heavy, r-process only isotopes (134 and 136). These excesses are always correlated although physical settings of these two processes are quite different and there is little reason to always correlate each other. Furthermore, the r-process Xe and the p-process Xe in diamond inferred from Xe-HL are quite different from what is derived from the solar system abundance as well as stellar models. Further studies are needed to investigate these outstanding problems for over three decades.
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تاریخ انتشار 2008