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arXiv · 2610.18707

Testing the 4-Point Correlation Function as a Probe of Parity Violation with the Quijote-Odd Simulations

William Ortolá Leonard·Zachary Slepian·Alex Krolewski·Simon May
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Abstract

We investigate parity violation searches with the 4-Point Correlation Function (4PCF) using the Quijote and Quijote-Odd halo catalogs. Specifically, we explore the auto- and cross-correlation searching methodologies that have been previously used in the Baryon Oscillation Spectroscopic Survey (BOSS) and the Dark Energy Spectroscopic Instrument (DESI) searches. Although the Quijote-Odd simulations are initialized with a parity-violating primordial trispectrum, we find no statistically detectable parity-odd signal in the halo 4PCF. Instead, we find that the halo measurements are dominated by Poisson noise. We are able to distinguish this noise-dominated behavior from the response expected for a parity-odd signal. These results clarify how parity-sensitive 4PCF statistics respond to noise in a controlled simulation setting.

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William Ortolá Leonard, Zachary Slepian, Alex Krolewski, Simon May. 2026-10-13. Testing the 4-Point Correlation Function as a Probe of Parity Violation with the Quijote-Odd Simulations. https://arxiv.org/abs/2610.18707

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