Neural network method for galaxy classification: the luminosity function of E/S0 in clusters
نویسندگان
چکیده
We present a method based on the non-linear behaviour of neural network for the identification of the early-type population in the cores of galaxy clusters. A Kohonen Self Organising Map applied on a three-colour photometric catalogue of objects enabled us to select in each passband the elliptical galaxies. We measured in this way the luminosity function of the E/S0 galaxies selected in this way. Such luminosity functions show peculiarities which disfavour the hypothesis of its universality often claimed for rich clusters and that can be related to the past dynamical history of the cluster as a whole.
منابع مشابه
Luminosity Function of Early-type Galaxies in Clusters Cores (as Selected by Ann)
We show the possibility to exploit the non-linear behaviour of artiicial neural network (ANN) for the identiication of the early-type component of the population of the core of clusters of galaxies. We result in a measurement of the luminosity function of the E/S0 galaxies which disfavours the hypothesis of a universal LF and calls for dynamical innuences.
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