Non-Gaussianities in Collider Energy Flux

Abstract

The microscopic dynamics of particle collisions is imprinted into the statistical properties of asymptotic energy flux, much like the dynamics of inflation is imprinted into the cosmic microwave background. This energy flux is characterized by correlation functions E( n 1 ) • • • E( n k ) of energy flow operators E( n). There has been significant recent progress in studying energy flux, including the calculation of multi-point correlation functions and their direct measurement inside high-energy jets at the Large Hadron Collider (LHC). In this paper, we build on these advances by defining a notion of "celestial non-gaussianity" as a ratio of the three-point function to a product of two-point functions. We show that this celestial non-gaussianity is under perturbative control within jets at the LHC, allowing us to cleanly access the non-gaussian interactions of quarks and gluons. We find good agreement between perturbative calculations of the non-gaussianity and a charged-particle-based analysis using CMS Open Data, and we observe a strong non-gaussianity peaked in the "flattened triangle" regime. The ability to robustly study three-point correlations is a significant step in advancing our understanding of jet substructure at the LHC. We anticipate that the celestial non-gaussianity, and its generalizations, will play an important role in the development of higher-order parton showers simulations and in the hunt for ever more subtle signals of potential new physics within jets.

Renormalization group flows for track function moments

“…Our results allow the calculation of up-to six point energy correlators on tracks, which have recently been investigated with CMS open data [65][66][67] providing a view on the hadronization transition, non-Gaussianities and quantum scaling dimensions. The threepoint energy correlator has also been proposed as a new way to extract the top quark mass [68], with the potential to reduce the theoretical uncertainty, particularly from nonperturbative effects.…”

Systematic Quark/Gluon Identification with Ratios of Likelihoods

“…[42]). One of the motivations for exploring in more detail the structure beyond the strict eikonal limit, is that there has recently been work on purely collinear jet substructure observables (the projected energy correlators, see [43][44][45][46][47][48][49][50][51][52] for more detailed discussions) that are sensitive to specific integer moments (the twist-2 spin-J anomalous dimensions) of the splitting functions. These observables are not correctly described by the leading eikonal result for the splitting function, and exhibit differences between quarks and gluons generated from the non-eikonal terms in the splitting function.…”