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| Paper: |
Origin of Short-lived Radionuclides in the Early Solar System |
| Volume: |
341, Chondrites and the Protoplanetary Disk |
| Page: |
485 |
| Authors: |
Goswami, J.N.; Marhas, K.K.; Chaussidon, M.; Gounelle, M.; Meyer, B.S. |
| Abstract: |
Evidence for the presence of about a dozen short-lived now-extinct radionuclides in the early solar system has been found in meteorites. The half-lives of these nuclides range from 100,000 years to more than a hundred million years. Three plausible modes of origin for these nuclides have been proposed. Some of them, particularly those with half-life more than several million years, could be products of continuous galactic nucleosynthesis, while others could be freshly synthesized stellar products injected into the protosolar molecular cloud or products of energetic particle interactions taking place in a presolar or early solar environment. The inferred abundances of these short-lived nuclides have been used to delineate time scales of processes taking place during the formation and early evolution of the solar system. In particular, inferences have been made about the time interval between the last addition of stellar nucleosynthesis products to the protosolar cloud and the formation of solar system objects, the time scale for the collapse of the protosolar cloud, the time interval between formation of various early solar system objects such as the Ca-Al-rich inclusions, chondrules and differentiated meteorites and also about the energetic particle environment in the early solar system. These inferences have strongly molded our current understanding of the origin and early evolution of the solar system. However, some of these inferences depend critically on our knowledge regarding the origin of short-lived radionuclides in the early solar system. It appears that different sets of nuclides may have different origins and some of them may have contributions from more than one source. In this chapter, we summarize the present status in this field and some of the robust conclusions that can be drawn about the origin of these nuclides. We also discuss analytical and experimental studies that are necessary to further our understanding in this regard. |
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