Star Cluster Formation in Cosmological Simulations. II. Effects of Star Formation Efficiency and Stellar Feedback

摘要: The implementation of star formation and stellar feedback in cosmological simulations plays a critical role shaping galaxy properties. In the first paper series, we presented new method to model as collection clusters. this paper, improve algorithm by eliminating accretion gaps, boosting momentum feedback, introducing subgrid initial bound fraction, $f_i$, that distinguishes cluster mass from particle mass. We perform suite with different efficiency per freefall time $\epsilon_{\rm ff}$ supernova intensity $f_{\rm boost}$. find history Milky Way-sized is sensitive boost}$, which allows us constrain its value, boost}\approx5$, current simulation setup. Changing few percent 200\% has little effect on global However, smaller scales, properties clusters are very ff}$. $f_i$ increases Through dependence shape function varies strongly fraction clustered maximum increase rate surface density, normalization both relations dependent timescale systematically decreases increasing Local variations gas lead 0.25~dex scatter for integral efficiency. Joint constraints all observables prefer runs produce median 16\%.