MÜNCHEN - Recent scientific findings shed light on the formation of the Sun, a process that began billions of years ago. Researchers have determined that the Sun formed from a precursor molecular cloud over a span of ten to twenty million years. This conclusion is based on the analysis of long-lived radionuclides found in meteorites.
The formation of the Sun, an intriguing chapter in cosmic history, is further elucidated by current scientific investigations. The study highlights the significance of the radionuclide 205Pb, which is produced exclusively through the astrophysical s-process in stars on the asymptotic giant branch (AGB stars). These stars, at the end of their burning cycle, are responsible for generating elements like 205Pb. The decay of 205Pb to 205Tl is a complex process occurring under extreme conditions in AGB stars.
Researchers utilized the GSI/FAIR heavy ion experimental storage ring to measure the bound beta decay of 205Tl. These measurements are unique worldwide and required the development of groundbreaking technologies to create the necessary conditions for successful experiments. The results allow for precise determination of the production rates of 205Pb in AGB stars.
These new findings have significant implications for understanding the Sun's formation. By comparing the amount of 205Pb in meteorites with the new decay rates, researchers have established a timeframe of ten to twenty million years for the Sun’s formation. These results align with data from other radioactive species produced through the slow neutron capture process.
The importance of this research lies not only in unraveling the past of our Sun but also in advancing astrophysical models. The collaboration among scientists from various countries and institutions demonstrates how international cooperation can lead to groundbreaking discoveries. The findings were published in the prestigious journal Nature, highlighting the unique capabilities of the heavy ion storage rings at GSI/FAIR.
Future experiments, such as investigating the neutron capture rate of 205Pb, could provide additional insights into the processes within stars. This research illustrates how experimental facilities and the collaboration of numerous research groups contribute to unraveling the mysteries of the universe and deepening our understanding of cosmic history.