Refractory phases in primitive meteorites devoid of Al-26 and Ca-41: Representative samples of first solar system solids?

A large number of Ca-Al-rich refractory inclusions in primitive meteorites incorporated the short-lived nuclide Al-26 at the time of their formation w ith an initial Al-26/Al-27 ratio of 5 x 10(-5). However, there exist inclus ions and refractory phases like corundum and hibonite in these meteorites t hat have no evidence of Al-26. A suite of refractory inclusions from these meteorites also have well-defined initial Al-26/Al-27 ratios that are lower by factors of 5-1000 compared to the canonical value of 5 x 10(-5). Refrac tory phases free of Al-26 are also devoid of the short-lived nuclide, Ca-41 . Heterogeneous distribution of the short-lived nuclides in the early solar system and possible formation of refractory inclusions from large clumps o f interstellar matter devoid of Al-26 are among the suggestions made to exp lain these observations. In this Letter, we suggest that the refractory pha ses devoid of Al-26 and Ca-41 represent some of the first solar system soli ds that formed in the inner region of the solar nebula prior to the injecti on of these freshly synthesized nuclides from a stellar source into this re gion.