The effects of population III stars on the chemical and photometrical evolution of ellipticals

Abstract

We have studied the effects of an hypothetical initial generation containing very massive stars (M > 100 Msun, pair-creation SNe) on the chemical and photometric evolution of elliptical galaxies. To this purpose, we have computed the evolution of a typical elliptical galaxy with luminous mass of the order of 10^11 Msun and adopted chemical evolution models already tested to reproduce the main features of ellipticals. We have tested several sets of yields for very massive zero-metallicity stars: these stars should produce quite different amounts of heavy elements than lower mass stars. We found that the effects of population III stars on the chemical enrichment is negligible if only one or two generations of such stars occurred, whereas they produce quite different results from the standard models if they continuously formed for a period not shorter than 0.1 Gyr. In this case, the results are at variance with the main observational constraints of ellipticals such as the average [<alpha/Fe>] ratio in stars and the integrated colors. Therefore, we conclude that if population III stars ever existed they must have been present for a very short period of time and their effects on the following evolution of the parent galaxy must have been negligible. This effect is minimum if a more realistic model with initial infall of gas rather than the classic monolithic model is adopted. Ultimately, we conclude that there is no need to invoke a generation of very massive stars in ellipticals to explain their chemical and photometric properties.

arXiv comment9 pages, 6 figures, MNRAS accepted

References in corpus (28)

• How Massive Single Stars End their Life
• The Nucleosynthetic Signature of Population III
• The Formation of the First Star in the Universe
• First stars V - Abundance patterns from C to Zn and supernova yields in the early Galaxy
• The Formation of the First Stars. I. The Primordial Star Forming Cloud
• Forming the First Stars in the Universe: The Fragmentation of Primordial Gas
• Nucleosynthesis of Zinc and Iron-Peak Elements in Pop III Type II Supernovae : Comparison with abundances of Very Metal-Poor Halo Stars
• The Formation and Fragmentation of Primordial Molecular Clouds
• A stellar relic from the early Milky Way
• First stars, very massive black holes and metals
• Explosive yields of massive stars from Z=0 to Z=Zsun
• Nucleosynthesis in Type Ia Supernovae
• The Universe Was Reionized Twice
• Oxygen, Carbon and Nitrogen evolution in galaxies
• Spatially resolved spectroscopy of Coma cluster early -- type galaxies: III. The stellar population gradients
• The evolution of the Milky Way from its earliest phases : constraints on stellar nucleosynthesis
• The Minimum Universal Metal Density Between Redshifts of 1.5 and 5.5
• Early Reionization by the First Galaxies
• HE0107-5240, A Chemically Ancient Star.I. A Detailed Abundance Analysis
• Photo-Chemical Evolution of Elliptical Galaxies I. The high-redshift formation scenario
• Implications of WMAP Observations On the Population III Star Formation Processes
• Galaxy Formation and Evolution: Low Surface Brightness Galaxies
• Structure, Evolution and Nucleosynthesis of Primordial Stars
• Evolution and Nucleosynthesis of Zero Metal Intermediate Mass Stars
• On the early evolution of the Galactic Halo
• Early Enrichment of Quasars by First Stars
• The chemical evolution of the Galaxy: the importance of stars with an initial mass larger than 40Mo
• The Case Against Bimodal Star Formation in Elliptical Galaxies

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• A Chandra Survey of Early-Type Galaxies, I: Metal Enrichment in the ISM
• An inhomogeneous model for the Galactic halo: a possible explanation for the spread observed in s- and r-process elements
• An Observational Pursuit for Population III Stars in a Ly_alpha Emitter at z=6.33 through HeII Emission
• Photo-chemical evolution of elliptical galaxies II. The impact of merging-induced starbursts
• On the effects of the Initial Mass Function on Galactic chemical enrichment
• A Study of the Merger History of the Galaxy Group HCG 62 Based on X-Ray Observations and SPH Simulations