%0 Generic %1 sun2015cluster %A Sun, Weijia %A de Grijs, Richard %A Fan, Zhou %A Cameron, Ewan %D 2015 %K cluster environment stochastic %T The star cluster mass--galactocentric radius relation: Implications for cluster formation %U http://arxiv.org/abs/1511.04490 %X Whether or not the initial star cluster mass function is established through a universal, galactocentric-distance-independent stochastic process, on the scales of individual galaxies, remains an unsolved problem. This debate has recently gained new impetus through the publication of a study that concluded that the maximum cluster mass in a given population is not solely determined by size-of-sample effects. Here, we revisit the evidence in favor and against stochastic cluster formation by examining the young ($łesssim$ a few $\times 10^8$ yr-old) star cluster mass--galactocentric radius relation in M33, M51, M83, and the Large Magellanic Cloud. To eliminate size-of-sample effects, we first adopt radial bin sizes containing constant numbers of clusters, which we use to quantify the radial distribution of the first- to fifth-ranked most massive clusters using ordinary least-squares fitting. We supplement this analysis with an application of quantile regression, a binless approach to rank-based regression taking an absolute-value-distance penalty. Both methods yield, within the $1\sigma$ to $3\sigma$ uncertainties, near-zero slopes in the diagnostic plane, largely irrespective of the maximum age or minimum mass imposed on our sample selection, or of the radial bin size adopted. We conclude that, at least in our four well-studied sample galaxies, star cluster formation does not necessarily require an environment-dependent cluster formation scenario, which thus supports the notion of stochastic star cluster formation as the dominant star cluster-formation process within a given galaxy.

@misc{sun2015cluster, abstract = {Whether or not the initial star cluster mass function is established through a universal, galactocentric-distance-independent stochastic process, on the scales of individual galaxies, remains an unsolved problem. This debate has recently gained new impetus through the publication of a study that concluded that the maximum cluster mass in a given population is not solely determined by size-of-sample effects. Here, we revisit the evidence in favor and against stochastic cluster formation by examining the young ($\lesssim$ a few $\times 10^8$ yr-old) star cluster mass--galactocentric radius relation in M33, M51, M83, and the Large Magellanic Cloud. To eliminate size-of-sample effects, we first adopt radial bin sizes containing constant numbers of clusters, which we use to quantify the radial distribution of the first- to fifth-ranked most massive clusters using ordinary least-squares fitting. We supplement this analysis with an application of quantile regression, a binless approach to rank-based regression taking an absolute-value-distance penalty. Both methods yield, within the $1\sigma$ to $3\sigma$ uncertainties, near-zero slopes in the diagnostic plane, largely irrespective of the maximum age or minimum mass imposed on our sample selection, or of the radial bin size adopted. We conclude that, at least in our four well-studied sample galaxies, star cluster formation does not necessarily require an environment-dependent cluster formation scenario, which thus supports the notion of stochastic star cluster formation as the dominant star cluster-formation process within a given galaxy.}, added-at = {2015-11-17T10:23:26.000+0100}, author = {Sun, Weijia and de Grijs, Richard and Fan, Zhou and Cameron, Ewan}, biburl = {https://www.bibsonomy.org/bibtex/24876084f1cb343bea8e600f63b67d691/miki}, description = {[1511.04490] The star cluster mass--galactocentric radius relation: Implications for cluster formation}, interhash = {0f34677be62f5832c1b9fd83f7b9c274}, intrahash = {4876084f1cb343bea8e600f63b67d691}, keywords = {cluster environment stochastic}, note = {cite arxiv:1511.04490Comment: ApJ, in press, 39 pages in AAS preprint format, 10 multi-panel figures (some reduced in size to match arXiv compilation routines)}, timestamp = {2015-11-17T10:23:26.000+0100}, title = {The star cluster mass--galactocentric radius relation: Implications for cluster formation}, url = {http://arxiv.org/abs/1511.04490}, year = 2015 }