Comparative studies of Population Synthesis Models in the frame work of modified Strömgren filters

Abstract

Evolutionary models form a vital part of stellar population research to understand their evolution, but despite their long history of development, they often misrepresent and misinterpret the properties of stellar population observed through broadband and spectroscopic measurements. With the growing numbers of these synthesis models, model comparison becomes an important analysis to choose a suitable model for upgrade. Along with the model comparison, we reinvestigate the technique of modified Strömgren photometry to measure reliable parameter-sensitive colours and estimate precise model ages and metallicities. The assessment of Rakos/Schulz models with GALEV and Worthey's Lick/IDS model find smaller colour variation: Δ(uz-vz) $\le$ 0.056, Δ(bz-yz) $\le$ -0.05 and Δ(vz-yz) $\le$ 0.061. The study conveys a good agreement of GALEV models with the modified Strömgren colours but with poor UV model predictions with the observed globular cluster data, while the spectroscopic models perform badly due to the use of older isochrone and stellar spectral libraries with inaccurate/insufficient knowledge of various stellar phases and their treatment. Overall, the assessment finds modified Strömgren photometry well suited to study different types stellar populations by mitigating the effects of the age-metallicity degeneracy.

15 pages, 3 figures, 1 table, Accepted, JOAA

References in corpus (7)

• The propagation of uncertainties in stellar population synthesis modeling I: The relevance of uncertain aspects of stellar evolution and the IMF to the derived physical properties of galaxies
• The propagation of uncertainties in stellar population synthesis modeling II: The challenge of comparing galaxy evolution models to observations
• GALEV evolutionary synthesis models - I. Code, input physics and web-interface
• Resolving galaxies in time and space: I: Applying STARLIGHT to CALIFA data cubes
• Comparing six evolutionary population synthesis models through spectral synthesis on galaxies
• Optical and near infra-red colours as a discriminant of the age and metallicity of stellar populations
• The Age of Ellipticals and the Color-Magnitude Relation