Probing Parity with Composite-Field Galaxy Correlators

17.04.2026 11:50 – 12:50

Detecting parity violation on cosmological scales would provide a striking clue to new physics in late or early Universe. Large-scale structure surveys offer the statistical power required to test such signatures. For scalar observables such as galaxy clustering, the leading parity-sensitive statistic is the trispectrum, whose high dimensionality makes direct measurement and noise estimation challenging. It is therefore desirable to construct lower-dimensional observables that retain sensitivity to parity-violating trispectrum signals. In this talk, I introduce a class of such observables, referred to as parity-odd kurto spectra, which arise as power spectra of composite fields constructed from the galaxy overdensity field. These statistics compress trispectrum information into one-dimensional pseudo–power spectra that can be measured using standard large-scale structure techniques. I present tests of the estimators on N-body simulations and discuss the dominant sources of noise affecting the measurements. Finally, I show results from analyses of BOSS and DESI galaxy samples using parity-odd kurto spectra and compare them with recent analyses of 4point correlation functions the same datasets.

Lieu

Bâtiment: Ecole de Physique

EP234

entrée libre