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arXiv · 1309.2763

Green galaxies in the COSMOS field

Zhizheng Pan·Xu Kong·Lulu Fan
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Abstract

We present a research of morphologies, spectra and environments of $\approx$ 2350 "green valley" galaxies at $0.2 0.7$. At $z<0.7$, the fractions of $M_{\ast}<10^{10.0}M_{\sun}$ green galaxies located in dense environment are found to be significantly larger than those of blue galaxies. The morphological and spectral properties of green galaxies are consistent with the transiting population between blue cloud and red sequence. The possible mechanisms for quenching star formation activities in green galaxies are discussed. The importance of AGN feedback cannot be well constrained in our study. Finally, our findings suggest that environment conditions, most likely starvation and harassment, significantly affect the transformation of $M_{\ast}<10^{10.0}M_{\sun}$ blue galaxies into red galaxies, especially at $z<0.5$.

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Zhizheng Pan, Xu Kong, Lulu Fan. 2013-09-11. Green galaxies in the COSMOS field. https://doi.org/10.1088/0004-637x%2F776%2F1%2F14

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