Aluminum and Oxygen Isotopic Ratios in Meteorite Grains: a Puzzle Solved By Nuclear and Stellar Physics

40th Symposium on Nuclear Physics 2017

Palmerini, Sara^1,2

Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Italy^1

I.N.F.N. Sezione di Perugia, Italy^2

关键词: Asymptotic giant branch;    Chemical evolution;    Interstellar mediums;    Isotopic abundances;    Isotopic composition;    Light elements;    Oxygen isotopic;    Stellar spectra;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/876/1/012018/pdf
DOI  :  10.1088/1742-6596/876/1/012018

来源: IOP

【 摘 要 】

Low mass stars contribute to the chemical evolution of the Galaxy as well as more massive supernova progenitors. Indeed the limited amount of processed matter released into the interstellar medium by small objects is compensated by the large number of them. At the late stages of their evolution, stars with mass smaller than 3Moundergo the Asymptotic Giant Branch phase, which has been found to be a unique site for synthesis of some nuclei heavier than Fe through slow neutron capture reactions. AGB nucleosynthesis is also characterized by H-burning coupled with mixing phenomena, which has been proved to account for anomalies in light element isotopic abundances from Li to Al observed in stellar spectra and meteorites. We present here the case of a large number of meteorite grains, whose isotopic composition offers a puzzles that only Nuclear and Stellar Physics coupled together might solve.