Abstract
A discrepancy exists between the 6Li abundances predicted from big bang nucleosynthesis models and those measured in pre-main sequence stars. To further constrain the predicted abundances of 6Li in these stars, high accuracy measurements are required of reactions destroying 6Li. Namely 6Li(p,γ)7Be and 6Li(p,α) 3He. These have recently been studied at the Laboratory for Underground Nuclear Astrophysics (LUNA) to measure their low energy cross sections. I present both the campaign’s experimental setup and current status of the data analysis.
Highlights
Following the recent sucess of the Wilkinson Microwave Anisotropy Probe (WMAP) experiment in measuring the footprint of the cosmic microwave background (CMB) [1], cosmologists are closer than ever to precisely model and understand big bang nucleosynthesis (BBN) [2] in the early universe
Of high interest to nuclear astrophysicists, the parameters obtained from BBN+WMAP data have been used to predict the present abundances of low mass isotopes found in stars
Whilst deuterium and 4He abundances show excellent agreement between those predicted by BBN+WMAP and those measured in galaxies [2], large discrepancies are found for 6Li and 7Li between BBN+WMAP predictions and measurements of low-metallicity, or pre-main sequence (PMS), stars
Summary
Following the recent sucess of the Wilkinson Microwave Anisotropy Probe (WMAP) experiment in measuring the footprint of the cosmic microwave background (CMB) [1], cosmologists are closer than ever to precisely model and understand big bang nucleosynthesis (BBN) [2] in the early universe. A recent review [3] suggests the predicted 7Li abundances are 2-4 times higher than those measured, and inversely the predicted 6Li abundances are 5000 times lower than measured. Whilst this large discrepancy is currently attributed to 6Li production via proton induced spallation and fusion reactions, the environments encountered in PMS stars are expected to destroy more 6Li than 7Li. To further constrain the predicted abundances of 6Li in PMS stars, further high accuracy measurements are required of the reactions burning 6Li. Understanding the destructive processes of 6Li to a higher accuracy will enable theorists to better model the inner profile of PMS stars. This profile can provide an indication of how the convective currents vary beneath the stellar surface [4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
