English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The mass distribution of dark matter halos is a sensitive probe of primordialnon-Gaussianity (NG). We derive an analytical formula of the halo mass functionby perturbatively computing excursion set path-integrals for a non-Gaussiandensity field with non-vanishing skewness, fnl. We assume a stochastic barriermodel which captures the main features of the ellipsoidal collapse of halos.Contrary to previous results based on extensions of the Press-Schechterformalism to NG initial conditions, we find that the non-spherical collapse ofhalos directly alter the signature of primordial NG. This points toward apotential degeneracy between the effect of primordial non-Gaussianity and thatof non-linear halo collapse. The inferred mass function is found to be inremarkable agreement with N-body simulations of NG local type. Deviations arewell within numerical uncertainties for all values of -80 < fNL^loc < 300 inthe range of validity of the perturbative calculation. Moreover, the comparisonwith simulation results suggests that for fNL > 150 or fNL < -50 the non-linearcollapse of halos, as described by our barrier model, strongly deviates fromthat of Gaussian initial conditions. This is not surprising since the effect ofnon-linear gravitational processes may be altered by initially large NG. Hence,in the lack of prior theoretical knowledge, halo collapse model parametersshould be included in statistical halo mass function data analysis which aim toconstrain the signature of primordial NG

Non-Gaussian Halo Mass Function and Non-Spherical Halo Collapse: Theory vs. Simulations