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arXiv · 1010.5242

Measuring primordial non-Gaussianity through weak lensing peak counts

Laura Marian·Stefan Hilbert·Robert E. Smith·Peter Schneider·Vincent Desjacques
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Abstract

We explore the possibility of detecting primordial non-Gaussianity of the local type using weak lensing peak counts. We measure the peak abundance in sets of simulated weak lensing maps corresponding to three models f_NL={0, +100, -100}. Using survey specifications similar to those of Euclid and without assuming any knowledge of the lens and source redshifts, we find the peak functions of the non-Gaussian models with f_NL=+-100 to differ by up to 15% from the Gaussian peak function at the high-mass end. For the assumed survey parameters, the probability of fitting an f_NL=0 peak function to the f_NL=+-100 peak functions is less than 0.1%. Assuming the other cosmological parameters known, f_NL can be measured with an error Δf_NL ~ 13. It is therefore possible that future weak lensing surveys like Euclid and LSST may detect primordial non-Gaussianity from the abundance of peak counts, and provide complementary information to that obtained from the cosmic microwave background.

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Laura Marian, Stefan Hilbert, Robert E. Smith, Peter Schneider, Vincent Desjacques. 2012-04-18. Measuring primordial non-Gaussianity through weak lensing peak counts. https://doi.org/10.1088/2041-8205%2F728%2F1%2Fl13

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