An α-stable approach to the study of the P(D) distribution of unresolved point sources in CMB sky maps

  title={An $\alpha$-stable approach to the study of the P(D) distribution of unresolved point sources in CMB sky maps},
  author={Diego Herranz and Ercan Engin Kuruoglu and Luigi Toffolatti},
  journal={Astronomy and Astrophysics},
We present a new approach to the statistical study and modelling of number counts of faint point sources in astro- nomical images, i.e. counts of sources whose flux falls below the detection limit of a survey. The approach is based on the theory of α-stable distributions. We show that the non-Gaussian distribution of the intensity fluctuations produced by a generic point source population - whose number counts follow a simple power law - belongs to the α-stable family of distributions. Even if… 

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