# Energy correlations in the end-point region

## TL;DR

This paper introduces a novel method for resumming large logarithmic corrections in energy-energy correlations at small and large angles, using four-point correlation functions and conformal symmetry, with applications to QCD and supersymmetric theories.

## Contribution

It develops a new approach linking energy correlations to four-point functions, enabling precise resummation in different angular regimes and providing predictions for QCD.

## Key findings

- Derived EEC from four-point functions at large angles.
- Resummed EEC at small angles in conformal theories.
- Validated results against NNLO calculations in supersymmetric Yang-Mills.

## Abstract

The energy-energy correlation (EEC) measures the angular distribution of the energy that flows through two calorimeters separated by some relative angle in the final state created by a source. We study this observable in the limit of small and large angles when it describes the correlation between particles belonging, respectively, to the same jet and to two almost back-to-back jets. We present a new approach to resumming large logarithmically enhanced corrections in both limits that exploits the relation between the energy correlations and four-point correlation functions of conserved currents. At large angle, we derive the EEC from the behaviour of the correlation function in the limit when four operators are light-like separated in a sequential manner. At small angle, in a conformal theory, we obtain the EEC from resummation of the conformal partial wave expansion of the correlation function at short-distance separation between the calorimeters. In both cases, we obtain a concise representation of the EEC in terms of the conformal data of twist-two operators and verify it by comparing with the results of explicit calculation at next-to-next-to-leading order in maximally supersymmetric Yang-Mills theory. As a byproduct of our analysis, we predict the maximal weight part of the analogous QCD expression in the back-to-back limit.