Dark Energy Survey Year 3 Results: Three-Point Shear Correlations and Mass Aperture Moments

TL;DR

This paper reports high signal-to-noise measurements of three-point shear correlations and mass aperture moments from three years of Dark Energy Survey data, providing new insights into cosmological structures and their evolution.

Contribution

It presents the first measurements of the configuration and scale dependence of three-point shear correlations and tomographic mass aperture moments using DES Year 3 data.

Findings

Measured shear 3pt functions agree with N-body simulation predictions.

Achieved 15.0σ significance in mass aperture third moment measurements.

Validated that signals are astrophysical and gravitational, with negligible systematics.

Abstract

We present high signal-to-noise measurements of three-point shear correlations and the third moment of the mass aperture statistic using the first 3 years of data from the Dark Energy Survey. We additionally obtain the first measurements of the configuration and scale dependence of the four three-point shear correlations which carry cosmological information. With the third-order mass aperture statistic, we present tomographic measurements over angular scales of 4 to 60 arcminutes with a combined statistical significance of 15.0$\sigma$. Using the tomographic information and measuring also the second-order mass aperture, we additionally obtain a skewness parameter and its redshift evolution. We find that the amplitudes and scale-dependence of these shear 3pt functions are in qualitative agreement with measurements in a mock galaxy catalog based on N-body simulations, indicating promise for including them in future cosmological analyses. We validate our measurements by showing that B-modes, parity-violating contributions and PSF modeling uncertainties are negligible, and determine that the measured signals are likely to be of astrophysical and gravitational origin.