Séminaire / Seminar GReCO |
| « New statistical methods for non-Gaussian astrophysical fields » |
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Erwan Allys |
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One of the major difficulties while working with cosmological
observations in non-linear regimes is to efficiently characterize their non-Gaussian features. This is for example necessary while studying the late time Large Scale Structure (LSS), or when modeling the CMB foregrounds. To study those highly non-Gaussian fields, no generic tool using high-order correlation functions has clearly emerged. Introducing an alternative method, I will present a new statistical description of non-Gaussian fields, which have been developed in data science and modified to be applied to physical processes. This method, that computes the covariance of phase harmonics of wavelet coefficients, is especially suited to statistical characterize the relative phase shifts between different scales. I will show how this method can be used to infer cosmological parameters from LSS maps, as well as to produce realistic statistical syntheses of such maps. I will also briefly show how these tools can be applied to the study of the galactic CMB foregrounds. |
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lundi 10 février 2020 - 11:00 Salle des séminaires Évry Schatzman Institut d'Astrophysique de Paris |
| Pages web du séminaire / Seminar's webpage |