Measurement of the Cross-Correlation Angular Power Spectrum Between the Stochastic Gravitational Wave Background and Galaxy Over-Density

Understand

We study the cross-correlation between the stochastic gravitational-wave background (SGWB) generated by binary black hole (BBH) mergers across the universe and the distribution of galaxies across the sky.

• We use the anisotropic SGWB measurement obtained using data from the third observing run (O3) of Advanced LIGO detectors and galaxy over-density obtained from the Sloan Digital Sky Survey (SDSS) spectroscopic catalog.
• We compute, for the first time, the angular power spectrum of their cross-correlation.
• Instead of integrating the SGWB across frequencies, we analyze the cross-correlation in 10 Hz wide SGWB frequency bands to study the frequency dependence of the cross-correlation angular power spectrum.