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arXiv · 1801.03736

Constraining gravity at large scales with the 2MASS Photometric Redshift catalogue and Planck lensing

Federico Bianchini·Christian L. Reichardt
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Abstract

We present a new measurement of structure growth at $z \simeq 0.08$ obtained by correlating the cosmic microwave background (CMB) lensing potential map from the \textit{Planck} satellite with the angular distribution of the 2MASS Photometric Redshift galaxies. After testing for, and finding no evidence for systematic effects, we calculate the angular auto- and cross-power spectra. We combine these spectra to estimate the amplitude of structure growth using the bias-independent $D_G$ estimator introduced by Giannantonio et al. 2016. We find that the relative amplitude of $D_G$ with respect to the predictions based on \textit{Planck} cosmology is $A_D(z=0.08) = 1.00 \pm 0.21$, fully consistent with the expectations for the standard cosmological model. Considering statistical errors only, we forecast that a joint analysis between an LSST-like photometric galaxy sample and lensing maps from upcoming ground-based CMB surveys like the Simons Observatory and CMB-S4 can yield sub-percent constraints on the growth history and differentiate between different models of cosmic acceleration.

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Federico Bianchini, Christian L. Reichardt. 2018-07-25. Constraining gravity at large scales with the 2MASS Photometric Redshift catalogue and Planck lensing. https://doi.org/10.3847/1538-4357%2Faacafd

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