Comparative Studies of Population Synthesis Models in the Framework of Modified Strömgren Filters

Journal of astrophysics and astronomy

Karl Rakos¹  Gerhard Hensler¹  Yuvraj Harsha Sreedhar1¹ 

[1] Institute of Astronomy, University of Vienna, Vienna, Austria.$$

关键词: Galaxy: evolution;    galaxy: formation;    galaxy: general;    galaxy: globular clusters: general galaxies: abundance;    galaxies: photometry;    galaxies: star clusters: general;    galaxies: star formation.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

Evolutionary models form a vital part of stellar population research in understanding their evolution, but despite their long history of development, they are often misrepresented and the properties of stellar population observed through broadband and spectroscopic measurements are also misinterpreted. With growing numbers of these synthesis models, model comparison becomes an important analysis to choose a suitable model for understanding stellar populations and model up-gradation. Along with model comparison, we reinvestigate the technique ofmodified 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) ≤ 0.056, 𝛥 (𝑏𝑧 - 𝑦𝑧) ≤ -0.05 and 𝛥 (𝑣𝑧 − 𝑦𝑧) ≤ 0.061. The study conveys a good agreement of GALEV models with modified Strömgren colours but with poor UV model predictions and observed globular cluster data, while the spectroscopic models perform badly because of outdated isochrone and stellar spectral libraries with inaccurate/insufficient knowledge of various stellar phases and their treatment.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 age-metallicity degeneracy.

【 授权许可】

Unknown