The effect of diffusion on the Red Giant luminosity function 'bump'

Abstract

This paper investigates the effect of microscopic diffusion of helium and heavy elements on the location of the Red Giant Branch Luminosity Function Bump in Population II stellar models. To this aim updated evolutionary models taking into account diffusion from the Main Sequence until the Zero Age Horizontal Branch have been computed. The observational luminosity difference between the RGB bump and the ZAHB, as collected for a sample of galactic globular clusters, has been compared with the corresponding theoretical values obtained by adopting both canonical and diffusive models. We find that the effect of diffusion, even if slightly improving the agreement between observations and theory, is negligible with respect to the observational uncertainties. In any case the theoretical predictions in models with and without diffusion appear in agreement with the observational results within the estimated errors. Thus canonical models can be still safely adopted, at least until much more accurate observational data will be available.

TeX, 6 pages, uses mnrass.sty (included), 2 postscript figures, in publication on MNRAS

Cited by in corpus (26)

• Evolutionary population synthesis: models, analysis of the ingredients and application to high-z galaxies
• The propagation of uncertainties in stellar population synthesis modeling III: model calibration, comparison, and evaluation
• A new model of galaxy formation: How sensitive are predicted galaxy luminosities to the choice of SPS model?
• Stellar mass estimates in early-type galaxies: procedures, uncertainties and models dependence
• Deep Extragalactic VIsible Legacy Survey (DEVILS): SED Fitting in the D10-COSMOS Field and the Evolution of the Stellar Mass Function and SFR-$M_{\star }$ relation
• Comparison between predicted and empirical DV(Bump -HB) in Galactic Globular Clusters
• The Red Giant Branch Luminosity Function Bump
• Theoretical Uncertainties in Red Giant Branch Evolution: The Red Giant Branch Bump
• The shape of the Red Giant Branch Bump as a diagnostic of partial mixing processes in low-mass stars
• Giants reveal what dwarfs conceal: Li abundance in lower RGB stars as diagnostic of the primordial Li
• Comparing six evolutionary population synthesis models through spectral synthesis on galaxies
• On the magnitude difference between the main sequence turn off and the red giant branch bump in Galactic globular clusters
• A Comprehensive Bayesian Discrimination of the Simple Stellar Population Model, Star Formation History and Dust Attenuation Law in the Spectral Energy Distribution Modeling of Galaxies
• Calibrating stellar population models with Magellanic Cloud star clusters
• Diagnostics of Stellar Modelling from Spectroscopy and Photometry of Globular Clusters
• The ${}^{14}N(p,\gamma {)}^{15}O$ reaction, solar neutrinos and the age of the globular clusters
• The Next Generation Virgo cluster Survey (NGVS). XXV. Fiducial panchromatic colors of Virgo core globular clusters and their comparison to model predictions
• Optical and near infra-red colours as a discriminant of the age and metallicity of stellar populations
• Probing Evolutionary Population Synthesis Models in the Near Infrared with Early Type Galaxies
• The Relation between Dynamical Mass-to-Light Ratio and Color for Massive Quiescent Galaxies out to z~2 and Comparison with Stellar Population Synthesis Models
• Investigating the Consistency of Stellar Evolution Models with Globular Cluster Observations via the Red Giant Branch Bump
• The Next Generation Virgo cluster Survey (NGVS). XXVI. The issues of photometric age and metallicity estimates for globular clusters
• A SINFONI view of the nuclear activity and circumnuclear star formation in NGC 4303 - II: Spatially resolved stellar populations
• Next Generation Virgo Cluster Survey (NGVS). XXXII:~Search for a Globular Cluster Substructure in the Virgo Galaxy Cluster Core
• Uncertainties and systematics in stellar evolution models of Red Giant Stars
• Yunnan-III models for Evolutionary population synthesis