The effect of enhanced helium abundances on the AGB-supernove mass transition

Amanda I. Karakas, Luke J. Shingles

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearch

1 Citation (Scopus)

Abstract

Globular clusters are now known to harbour helium-rich stellar populations. While the stars we see today are all of low mass, there were once stars of all mass ranges with helium mass fractions up to Y ≈ 0.40. It has also been suggested that the younger stellar component of the Galactic bulge is both metal-rich and helium rich, with Y up to 0.40. In this study we investigate the effect of helium enrichment on the stellar evolution of stars near the AGB-supernova mass transition, which is 8 Msun for solar metallicity. In particular we show that the AGB-supernova mass transition decreases in mass with increasing helium abundance, for both metal-poor and metal-rich models. This will have an impact on the stellar yields and on the chemical evolution of helium rich stellar populations.

Original languageEnglish
Title of host publicationMemorie della Societa Astronomica Italiana
Subtitle of host publication2017 AGB-Supernovae Mass Transition; Monte Porzio Catone; Italy; 27 March 2017 through 31 March 2017
EditorsA Karakas, P Ventura, F Dell'Agli, M Di Criscienzo
Place of PublicationItaly
PublisherFabrizio Serra Editore
Pages244-247
Number of pages4
Volume88
Edition3
Publication statusPublished - 2017
EventAGB-Supernovae Mass Transition, 2017 - Observatory of Rome, Monte Porzio Catone, Italy
Duration: 27 Mar 201731 Mar 2017
https://agb-supernovae.weebly.com/

Publication series

NameSocieta Astronomica Italiana. Memorie
PublisherFabrizio Serra Editore
ISSN (Print)0037-8720

Conference

ConferenceAGB-Supernovae Mass Transition, 2017
Abbreviated title2017 AGB
Country/TerritoryItaly
CityMonte Porzio Catone
Period27/03/1731/03/17
OtherScientific topics
- An update on AGB and Super-AGB models.
- Dust formation from AGB stars and SNe
- Mass-Mcore relations. The boundary in mass with SN II explosions and the mass transition from super-AGB to AGB.
- Evolution into SNII, electron-capture SNe, SNIa, subtypes.
- Observed rates of different types of SNe in different contexts.
- Binary population synthesis for SNIa rates. Binary evolution to SNII.
- Role of super-AGB stars and SN explosions in the context of the formation of multiple populations in Globular Clusters.
- Observational constrains on AGB, super-AGB and massive stars populations,
​ obscured and not.
Internet address

Keywords

  • Galaxy: abundances, nucleosynthesis, abundances
  • ISM: abundances
  • Stars: abundances, stars: AGB and post-AGB

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