Can the CIB constrain the dark energy?
Résumé
Galaxies are often used as tracers of the large scale structure (LSS) to measurethe Integrated Sachs-Wolfe effect (ISW) by cross-correlating the galaxy surveymaps with the Cosmic Microwave Background (CMB) map. We use the Cosmic InfraredBackground (CIB) as a tracer of the LSS to perform a theoretical CIB-CMB cross-correlation to measure the ISW for different Planck HFI frequencies. We discussthe detectability of this ISW signal using a Signal-to-noise ratio analysis andfind that the ISW detected this way can provide us with the highest SNR for asingle tracer ranging from 5 to 6.7 (maximum being for 857 GHz) with the CIB andCMB maps extracted over the whole sky. A Fisher matrix analysis showed that thismeasurement of the ISW can improve the constraints on the cosmologicalparameters; especially the equation of state of the dark energy w by ∼ 47%.Performing a more realistic analysis including the galactic dust residuals inthe CIB maps over realistic sky fractions shows that the dust power spectradominate over the CIB power spectra at < 100 and ISW can't be detected with highSNR. We perform the cross-correlation on the existing CIB-CMB maps over ∼ 11% ofthe sky in the southern hemisphere and find that the ISW is not detected withthe existing CIB maps over such small sky fractions.