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arXiv · 1401.7878

A new method for classifying galaxy SEDs from multi-wavelength photometry

Vivienne Wild·Omar Almaini·Michele Cirasuolo·Jim Dunlop·Ross McLure·Rebecca Bowler·Joao Ferreira·Emma Bradshaw·Robert Chuter·Will Hartley
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Abstract

We present a new method to classify the broad band optical-NIR spectral energy distributions (SEDs) of galaxies using three shape parameters (super-colours) based on a Principal Component Analysis of model SEDs. As well as providing a compact representation of the wide variety of SED shapes, the method allows for easy visualisation of information loss and biases caused by the incomplete sampling of the rest-frame SED as a function of redshift. We apply the method to galaxies in the UKIDSS Ultra Deep Survey with 0.9 11, declining steadily to 13% at log(M*/Msol)=10. The properties and mass-function of the post-starburst galaxies are consistent with a scenario in which gas-rich mergers contribute to the growth of the low and intermediate mass range of the red sequence.

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Vivienne Wild, Omar Almaini, Michele Cirasuolo, Jim Dunlop, Ross McLure, Rebecca Bowler, Joao Ferreira, Emma Bradshaw, Robert Chuter, Will Hartley. 2014-01-30. A new method for classifying galaxy SEDs from multi-wavelength photometry. https://doi.org/10.1093/mnras%2Fstu212

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