Metallicities of Young Massive Clusters in NGC 5236 (M83)
Abstract
We present integrated-light spectra of 8 Young Massive Clusters (YMCs) in the metal-rich spiral galaxy NGC 5236 (M 83). The observations were taken with the X-Shooter spectrograph on the ESO Very Large Telescope. Through the use of theoretical isochrones and synthetic integrated-light (IL) spectra we derive metallicities and study the radial metallicity gradient observed through these young populations. For the inner regions of the galaxy we observe a relatively shallow metallicity gradient of -0.37 0.29 dex R25-1, agreeing with chemical evolution models with an absence of infall material and a relatively low mass loss due to winds in the inner parts of the disk. We estimate a central metallicity of [Z] = +0.17 0.12 dex, finding excellent agreement with that obtained via other methods (e.g. blue supergiants and J-band). We infer a metallicity of 12+log(O/H) = 8.75 0.08 dex at R/R25 = 0.4, which fits the stellar mass-metallicity relation (MZR) compilation of blue supergiants and IL studies.