Abstract

Diffuse gamma-ray emission from the decay of radioactive 26Al is a messenger from the nucleosynthesis activity in our current-day galaxy. Because this material is attributed to ejections from massive stars and their supernovae, the gamma-ray signal includes information about nucleosynthesis in massive star interiors as it varies with evolutionary stages, and about their feedback on the surrounding interstellar medium. Our method of population synthesis of massive-star groups has been refined as a diagnostic tool for this purpose. It allows to build a bottom-up prediction of the diffuse gamma-ray sky when known massive star group distributions and theoretical models of stellar evolution and core-collapse supernova explosions are employed. We find general consistency of an origin in such massive-star groups, in particular we also find support for the clumpy distribution of such source regions across the Galaxy, and characteristics of large cavities around these. A discrepancy in the integrated 26Al gamma-ray flux is interpreted as an indication for excess 26Al emission from nearby, distributed in cavities that extend over major regions of the sky.

Details

Title
Gamma-ray spectroscopy of galactic nucleosynthesis
Author
Diehl, Roland; Greiner, Jochen; Martin G.H. Krause; Moritz M.M. Pleintinger; Siegert, Thomas
Section
Galactic Chemical Evolution / Presolar Radioactivities
Publication year
2023
Publication date
2023
Publisher
EDP Sciences
ISSN
21016275
e-ISSN
2100014X
Source type
Conference Paper
Language of publication
English
ProQuest document ID
3193641106
Copyright
© 2023. This work is licensed under https://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and conditions, you may use this content in accordance with the terms of the License.