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arXiv · 1207.4796

Primordial Bispectrum and Trispectrum Contributions to the Non-Gaussian Excursion Set Halo Mass Function with Diffusive Drifting Barrier

Ixandra E. Achitouv·Pier Stefano Corasaniti
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Abstract

The high-mass end of the halo mass function is a sensitive probe of primordial non-Gaussianity (NG). In a recent study [9] we have computed the NG halo mass function in the context of the Excursion Set theory and shown that the primordial NG imprint is coupled to that induced by the non-linear collapse of dark matter halos. We also found an excellent agreement with N-body simulation results. Here, we perform a more accurate computation which accounts for the interval validity of the bispectrum expansion to next-to-leading order and extend the calculation to the case of a non-vanishing primordial trispectrum.

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Ixandra E. Achitouv, Pier Stefano Corasaniti. 2013-01-15. Primordial Bispectrum and Trispectrum Contributions to the Non-Gaussian Excursion Set Halo Mass Function with Diffusive Drifting Barrier. https://doi.org/10.1103/physrevd.86.083011

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