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تسجيل مستخدم جديدMatching the Evolution of the Stellar Mass Function Using Log-normal Star Formation Histories
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Louis E. Abramson
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We show that a model consisting of individual, log-normal star formation histories for a volume-limited sample of $zapprox0$ galaxies reproduces the evolution of the total and quiescent stellar mass functions at $zlesssim2.5$ and stellar masses $M_*geq10^{10},{rm M_odot}$. This model has previously been shown to reproduce the star formation rate/stellar mass relation (${rm SFR}$--$M_*$) over the same interval, is fully consistent with the observed evolution of the cosmic ${rm SFR}$ density at $zleq8$, and entails no explicit quenching prescription. We interpret these results/features in the context of other models demonstrating a similar ability to reproduce the evolution of (1) the cosmic ${rm SFR}$ density, (2) the total/quiescent stellar mass functions, and (3) the ${rm SFR}$--$M_*$ relation, proposing that the key difference between modeling approaches is the extent to which they stress/address diversity in the (starforming) galaxy population. Finally, we suggest that observations revealing the timescale associated with dispersion in ${rm SFR}(M_*)$ will help establish which models are the most relevant to galaxy evolution.
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