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 language | English |
|---|---|
| Title of host publication | Memorie della Societa Astronomica Italiana |
| Subtitle of host publication | 2017 AGB-Supernovae Mass Transition; Monte Porzio Catone; Italy; 27 March 2017 through 31 March 2017 |
| Editors | A Karakas, P Ventura, F Dell'Agli, M Di Criscienzo |
| Place of Publication | Italy |
| Publisher | Fabrizio Serra Editore |
| Pages | 244-247 |
| Number of pages | 4 |
| Volume | 88 |
| Edition | 3 |
| Publication status | Published - 2017 |
| Event | AGB-Supernovae Mass Transition, 2017 - Observatory of Rome, Monte Porzio Catone, Italy Duration: 27 Mar 2017 → 31 Mar 2017 https://agb-supernovae.weebly.com/ |
Publication series
| Name | Societa Astronomica Italiana. Memorie |
|---|---|
| Publisher | Fabrizio Serra Editore |
| ISSN (Print) | 0037-8720 |
Conference
| Conference | AGB-Supernovae Mass Transition, 2017 |
|---|---|
| Abbreviated title | 2017 AGB |
| Country/Territory | Italy |
| City | Monte Porzio Catone |
| Period | 27/03/17 → 31/03/17 |
| Other | Scientific 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