The predicted properties of helium-enriched globular cluster progenitors at high redshift
| Autor: | Guglielmo Costa, David M. Nataf, Yang Chen, Yuan-Sen Ting, Shunsaku Horiuchi, Rosemary F. G. Wyse, Roland M. Crocker, Christoph Federrath |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Stellar mass
Galactic astronomy Metallicity Population FOS: Physical sciences Context (language use) Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics 01 natural sciences 0103 physical sciences Astrophysics::Solar and Stellar Astrophysics education 010303 astronomy & astrophysics Solar and Stellar Astrophysics (astro-ph.SR) Astrophysics::Galaxy Astrophysics Physics education.field_of_study 010308 nuclear & particles physics Astronomy and Astrophysics Astrophysics - Astrophysics of Galaxies Redshift Stars Astrophysics - Solar and Stellar Astrophysics 13. Climate action Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) Globular cluster Astrophysics::Earth and Planetary Astrophysics |
| Zdroj: | Monthly Notices of the Royal Astronomical Society. 496:3222-3234 |
| ISSN: | 1365-2966 0035-8711 |
| DOI: | 10.1093/mnras/staa1351 |
| Popis: | Globular cluster progenitors may have been detected by \textit{HST}, and are predicted to be observable with \textit{JWST} and ground-based extremely-large telescopes with adaptive optics. This has the potential to elucidate the issue of globular cluster formation and the origins of significantly helium-enriched subpopulations, a problem in Galactic astronomy with no satisfactory theoretical solution. Given this context, we use model stellar tracks and isochrones to investigate the predicted observational properties of helium-enriched stellar populations in globular cluster progenitors. We find that, relative to helium-normal populations, helium-enriched (${\Delta}Y=+0.12$) stellar populations similar to those inferred in the most massive globular clusters, are expected, modulo some rapid fluctuations in the first $\sim$30 Myr, to be brighter and redder in the rest frame. At fixed age, stellar mass, and metallicity, a helium-enriched population is predicted to converge to being $\sim$0.40 mag brighter at $\lambda \approx 2.0\, {\mu}m$, and to be 0.30 mag redder in the \textit{JWST}-NIRCam colour $(F070W-F200W)$, and to actually be fainter for $\lambda \lesssim 0.50 \, {\mu}m$. Separately, we find that the time-integrated shift in ionizing radiation is a negligible $\sim 5\%$, though we show that the Lyman-$\alpha$ escape fraction could end up higher for helium-enriched stars. Comment: Accepted for publication in MNRAS on 13 May, 2020 Replaced to update some bibliographic information |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|