VI/157ivo://CDS.VizieR/VI/157CDSGoudfrooij P.Asa'd R.2021-09-09T13:03:18Z2021-01-06T10:46:45ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frastronomical-modelsstellar-populationsspectroscopyIn this second paper of a series on the accuracy and precision of the determination of age and metallicity of simple stellar populations (SSPs) by means of the full spectrum fitting technique, we study the influence of star cluster mass through stochastic fluctuations of the number of stars near the top of the stellar mass function, which dominate the flux in certain wavelength regimes depending on the age.We consider SSP models based on the Padova isochrones, spanning the age range 7.0<=log(age/yr)<=10.1. Simulated spectra of star clusters in the mass range 10^4^<=M/M_{sun}_<10^6^ are compared with SSP model spectra to determine best-fit ages and metallicities using a full-spectrum fitting routine in four wavelength regimes: the blue optical (0.35-0.70um), the red optical (0.6-1.0um), the near-IR (1.0-2.5um), and the mid-IR (2.5-5.0um). We compare the power of each wavelength regime in terms of both the overall precision of age and metallicity determination, and of its dependence on cluster mass. We also study the relevance of spectral resolution in this context by utilizing two different spectral libraries (BaSeL and BT-Settl). We highlight the power of the mid-IR regime in terms of identifying young massive clusters in dusty star forming regions in distant galaxies. The spectra of the simulated star clusters and SSPs are made available online to enable follow-up studies by the community.2021MNRAS.501..440Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/VI/157CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=VI/157https://vizier.iucaa.in/viz-bin/VizieR-2?-source=VI/157http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=VI/157https://vizier.cds.unistra.fr/viz-bin/votable?-source=VI/157https://vizier.iucaa.in/viz-bin/votable?-source=VI/157http://vizieridia.saao.ac.za/viz-bin/votable?-source=VI/157GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultVI/157/listList of individual spectraspShow the spectrummeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFileNameName of the spectrum file with localisationmeta.id;meta.filecharTitleTitle of the filemeta.title;meta.filechar