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Lensing effect on the relative orientation between the Cosmic Microwave Background ellipticities and the distant galaxies

L. Van Waerbeke·F. Bernardeau·K. Benabed
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Abstract

The low redshift structures of the Universe act as lenses in a similar way on the Cosmic Microwave Background light and on the distant galaxies (say at redshift about unity). As a consequence, the CMB temperature distortions are expected to be statistically correlated with the galaxy shear, exhibiting a non-uniform distribution of the relative angle between the CMB and the galactic ellipticities. Investigating this effect we find that its amplitude is as high as a 10% excess of alignement between CMB and the galactic ellipticities relative to the uniform distribution. The relatively high signal-to-noise ratio we found should makes possible a detection with the planned CMB data sets, provided that a galaxy survey follow up can be done on a sufficiently large area. It would provide a complementary bias-independent constraint on the cosmological parameters.

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L. Van Waerbeke, F. Bernardeau, K. Benabed. 1999-10-20. Lensing effect on the relative orientation between the Cosmic Microwave Background ellipticities and the distant galaxies. https://doi.org/10.1086/309301

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