Group II Oxide Grains: How Massive Are Their AGB Star Progenitors?

Presolar grains and their isotopic compositions provide valuable constraints to AGB star nucleosynthesis. However, there is a sample of O- and Al-rich dust, known as group 2 oxide grains, whose origin is difficult to address. On the one hand, the 17O/16O isotopic ratios shown by those grains are sim...

Full description

Saved in:
Bibliographic Details
Published in:Universe (Basel) 2021-06, Vol.7 (6), p.175
Main Authors: Palmerini, Sara, Cristallo, Sergio, Piersanti, Luciano, Vescovi, Diego, Busso, Maurizio
Format: Article
Language:English
Subjects:
AGB star
Aluminum
Dust
Isotopes
isotopic abundance
Nuclear physics
Nucleosynthesis-Star: abundances
presolar grain
reaction rate
Silica
Stars
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Presolar grains and their isotopic compositions provide valuable constraints to AGB star nucleosynthesis. However, there is a sample of O- and Al-rich dust, known as group 2 oxide grains, whose origin is difficult to address. On the one hand, the 17O/16O isotopic ratios shown by those grains are similar to the ones observed in low-mass red giant stars. On the other hand, their large 18O depletion and 26Al enrichment are challenging to account for. Two different classes of AGB stars have been proposed as progenitors of this kind of stellar dust: intermediate mass AGBs with hot bottom burning, or low mass AGBs where deep mixing is at play. Our models of low-mass AGB stars with a bottom-up deep mixing are shown to be likely progenitors of group 2 grains, reproducing together the 17O/16O, 18O/16O and 26Al/27Al values found in those grains and being less sensitive to nuclear physics inputs than our intermediate-mass models with hot bottom burning.
ISSN:2218-1997
2218-1997
DOI:10.3390/universe7060175