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arXiv · 1108.2265

Canny Algorithm: A New Estimator for Primordial Non-Gaussianities

Rebecca J. Danos·Andrew R. Frey·Yi Wang
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Abstract

We utilize the Canny edge detection algorithm as an estimator for primordial non-Gaussianities. In preliminary tests on simulated sky patches with a window size of 57 degrees and multipole moments $l$ up to 1024, we find a $3σ$ distinction between maps with local non-Gaussianity $f_{NL}=350$ (or $f_{NL}=-700$) and Gaussian maps. We present evidence that high resolution CMB studies will strongly enhance the sensitivity of the Canny algorithm to non-Gaussianity, making it a promising technique to estimate primordial non-Gaussianity.

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Rebecca J. Danos, Andrew R. Frey, Yi Wang. 2012-03-19. Canny Algorithm: A New Estimator for Primordial Non-Gaussianities. https://doi.org/10.1103/physrevd.86.043526

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