%0 Journal Article
%T The growth of the disk galaxy UGC8802
%A R. X. Chang
%A S. Y. Shen
%A J. L. Hou
%J Physics
%D 2012
%I arXiv
%R 10.1088/2041-8205/753/1/L10
%X The disk galaxy UGC8802 has high neutral gas content and a flat profile of star formation rate compared to other disk galaxies with similar stellar mass. It also shows a steep metallicity gradient. We construct a chemical evolution model to explore its growth history by assuming its disk grows gradually from continuous gas infall, which is shaped by a free parameter -- the infall-peak time. By adopting the recently observed molecular surface density related star formation law, we show that a late infall-peak time can naturally explain the observed high neutral gas content, while an inside-out disk formation scenario can fairly reproduce the steep oxygen abundance gradient. Our results show that most of the observed features of UGC8802 can be well reproduced by simply `turning the knob' on gas inflow with one single parameter, which implies that the observed properties of gas-rich galaxies could also be modelled in a similar way.
%U http://arxiv.org/abs/1206.0842v1