Cafe-Club, Richard FEDER-STAEHLE (Caltech): “PCAT-DE: Reconstructing point-like and diffuse emission using spatial and spectral information”

Richard FEDER-STAEHLE (Caltech): “PCAT-DE: Reconstructing point-like and diffuse emission using spatial and spectral information”

You can find the schedule of upcoming café-clubs and the video of old ones here.

Take care,
Carlo, Meriam, Mathilde

ABSTRACT

I will present recent progress on probabilistic cataloging (PCAT), a transdimensional, Bayesian hierarchical modelling framework initially designed for crowded field photometry. I will discuss the extension to simultaneously model point-like and diffuse signals (PCAT-DE), enabling robust photometry in images with spatially varying foregrounds and, conversely, measurement of diffuse signals in the presence of point source contamination. While this machinery has been used successfully on real data (Butler & Feder 2022), I will present two applications characterizing its performance on synthetic multi-band Herschel-SPIRE maps. The first uses PCAT-DE to perform detection and photometry of CIB galaxies in the presence of galactic cirrus emission, while in the second we show that the spatially extended thermal Sunyaev-Zel’dovich effect signal can be measured in galaxy clusters even when it is subdominant to the point-like emission of CIB galaxies.