English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Evolutionary synthesis models are the prime method to construct models ofstellar populations, and to derive physical parameters from observations. Oneof the assumptions for such models so far has been the time-independence of thestellar mass function. However, dynamical simulations of star clusters in tidalfields have shown the mass function to change due to the preferential removalof low-mass stars from clusters. Here we combine the results from dynamicalsimulations of star clusters in tidal fields with our evolutionary synthesiscode GALEV to extend the models by a new dimension: the total clusterdisruption time. We reanalyse the mass function evolution found in N-bodysimulations of star clusters in tidal fields, parametrise it as a function ofage and total cluster disruption time and use this parametrisation to computeGALEV models as a function of age, metallicity and the total cluster disruptiontime. We study the impact of cluster dissolution on the colour (generally, theybecome redder) and magnitude (they become fainter) evolution of star clusters,their mass-to-light ratios (off by a factor of ~2 -- 4 from standardpredictions), and quantify the effect on the cluster age determination fromintegrated photometry (in most cases, clusters appear to be older than theyare, between 20 and 200%). By comparing our model results with observed M/Lratios for old compact objects in the mass range 10^4.5 -- 10^8 Msun, we find astrong discrepancy for objects more massive than 10^7 Msun (higher M/L). Thiscould be either caused by differences in the underlying stellar mass functionor be an indication for the presence of dark matter in these objects. Lessmassive objects are well represented by the models. The models for a range oftotal cluster disruption times are available online. (shortened)

The photometric evolution of dissolving star clusters: II. Realistic models. Colours and M/L ratios