HEP Theory Journal Club

Learning the Morphology and Small-Scale Structure of the Galactic Center Gamma-ray Excess

Yitian Sun

McGill University

Since its discovery, debates have been ongoing about the Galactic Center gamma-ray Excess (GCE) and its nature -- whether it arises from millisecond pulsars or annihilating dark matter. To distinguish these hypotheses, studies focused on examining the GCE’s morphology and small-scale photon clustering. However, most studies have relied on fits using inflexible templates for the signal and the background, which have been shown to be unreliable due to mis-modeling. In this talk, I will present a first attempt at modeling the GCE with a Gaussian process -- a flexible, non-parametric morphological model. I will then present an analysis of the small-scale structure featuring a unprecedented level of template flexibility. I will introduce our pipelines enabled by powerful yet fully interpretable machine learning techniques, discuss the results and their implications for the current status of our understanding of the GCE, and outline the future directions of our work. Title: Gravity and a universal cutoff for field theory.