Origin and Evolution of the Light Nuclides

摘要: After a short historical (and highly subjective) introduction to the field, I discuss our current understanding of origin and evolution light nuclides D, 3He, 4He, 6Li, 7Li, 9Be, 10B 11B. Despite considerable observational theoretical progress, important uncertainties still persist for each every one those nuclides. The present-day abundance D in local interstellar medium is currently uncertain, making it difficult infer recent chemical solar neighborhood. To account observed quasi-constancy 3He from Big Bang days, stellar production that nuclide must be negligible; however, scarce observations its planetary nebulae seem contradict this idea. Be B as primaries suggests source composition cosmic rays has remained ∼constant since early days Galaxy, suggestion with far reaching implications rays; main idea proposed constancy, namely superbubbles are at rays, encounters some serious difficulties. best explanation mismatch between primordial Li “Spite-plateau” halo stars appears depletion envelopes, by yet poorly understood mechanism. But impacts on level recently discovered “6Li plateau”, which (if confirmed), seriously challenges ideas ray nucleosynthesis.