Suppression of globular cluster formation in metal-poor gas clouds by Lyman α radiation feedback
Abstract
We study the impact of Ly α radiation feedback on globular cluster (GC) formation. In this Letter, we analytically derive the relation between star formation efficiency (SFE) and metallicity in spherical clouds with the Ly α radiation feedback. Our models show that the SFE becomes small as the metallicity decreases. In metal-poor gas clouds, Ly α photons are trapped for a long time and exert strong radiation force to the gas, resulting in the suppression of star formation. We find that bound star clusters (SFE ≳ 0.5) form only for the metallicity higher than ∼ 10- 2.5 Z⊙ in the case with the initial cloud mass 105 M⊙ and the radius 5 pc. Our models successfully reproduce the lower bound of observed metallicity of GCs. Thus, we suggest that the Ly α radiation feedback can be essential in understanding the formation of GCs.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- March 2018
- DOI:
- 10.1093/mnrasl/sly018
- arXiv:
- arXiv:1801.10473
- Bibcode:
- 2018MNRAS.475L.130A
- Keywords:
-
- radiative transfer;
- dust;
- extinction;
- globular clusters: general;
- galaxies: formation;
- galaxies: high-redshift;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 5 pages, 3 figures, accepted for publication in MNRAS Letter