English
Related papers

Related papers: Number Counts and Non-Gaussianity

200 papers

We compare the efficiency of weak lensing-selected galaxy clusters counts and of the weak lensing bispectrum at capturing non-Gaussian features in the dark matter distribution. We use the halo model to compute the weak lensing power…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Joel Berge , Adam Amara , Alexandre Refregier

We analyze primordial non-gaussianities in presence of an ultra-slow phase during the inflationary dynamics, focusing on scenarios relevant for the production of primordial black holes. We compute the three-point correlation function of…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-25 Marco Taoso , Alfredo Urbano

The existence (and abundance) of primordial black holes (PBHs) is governed by the power spectrum of primordial perturbations generated during inflation. So far no PBHs have been observed, and instead, increasingly stringent bounds on their…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-06 Yashar Akrami , Florian Kuhnel , Marit Sandstad

We develop the non-linear statistics of primordial black holes generated by a gaussian spectrum of primordial curvature perturbations. This is done by employing the compaction function as the main statistical variable under the constraints…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-25 Cristiano Germani , Ravi K. Sheth

We present a non-perturbative method for calculating the abundance of primordial black holes given an arbitrary one-point probability distribution function for the primordial curvature perturbation, $P(\zeta)$. A non-perturbative method is…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-01 Andrew D. Gow , Hooshyar Assadullahi , Joseph H. P. Jackson , Kazuya Koyama , Vincent Vennin , David Wands

We implement a novel formalism to constrain primordial non-Gaussianity of the local type from the large-scale modulation of the small-scale power spectrum. Our approach combines information about primordial non-Gaussianity contained in the…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-06 Utkarsh Giri , Moritz Münchmeyer , Kendrick M. Smith

Primordial black holes (PBHs) can form in the early Universe from the collapse of rare, large density fluctuations. They have never been observed, but this fact is enough to constrain the amplitude of fluctuations on very small scales which…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-20 Sam Young , Christian T. Byrnes

Events like inflation or phase transitions can produce large density perturbations on very small scales in the early Universe. Probes of small scales are therefore useful for e.g. discriminating between inflationary models. Until recently,…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-13 Pat Scott , Torsten Bringmann , Yashar Akrami

One of the main signatures of primordial non-Gaussianity of the local type is a scale-dependent correction to the bias of large-scale structure tracers such as galaxies or clusters, whose amplitude depends on the bias of the tracers itself.…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-11 Nico Hamaus , Uros Seljak , Vincent Desjacques

Ultracompact minihalos (UCMHs) have emerged as a valuable probe of the primordial power spectrum of density fluctuations at small scales. UCMHs are expected to form at early times in regions with ${\delta\rho/\rho \gtrsim 10^{-3}}$, and…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-07 M. Sten Delos , Adrienne L. Erickcek , Avery P. Bailey , Marcelo A. Alvarez

The cosmic microwave background (CMB) observation by the Planck satellite precisely determines primordial curvature fluctuations on larger scales than $\mathcal O(1)\,\mathrm{Mpc}$, while the small-scale curvature fluctuation is still less…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-06 Masahiro Kawasaki , Hiromasa Nakatsuka , Kazunori Nakayama

We show that the ability to probe primordial non-Gaussianity with cluster counts is drastically improved by adding the excess variance of counts which contains information on the clustering. The conflicting dependences of changing the mass…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-15 Masamune Oguri

Enhanced density fluctuations on small scales would lead to the formation of numerous dark matter minihalos, so limits on the minihalo abundance can place upper bounds on the small-scale primordial power spectrum. In particular, the…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-01 M. Sten Delos , Adrienne L. Erickcek , Avery P. Bailey , Marcelo A. Alvarez

Explaining the origin of supermassive black holes via a primordial origin is severely challenged by the tight spectral distortion constraints on the amplitude of the primordial perturbations. Following the first calculation of how the $\mu$…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-01 Christian T. Byrnes , Julien Lesgourgues , Devanshu Sharma

For primordial perturbations, deviations from Gaussian statistics on the tail of the probability distribution can be associated with non-perturbative effects of inflation. In this paper, we present some particular examples in which the tail…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-02 Yi-Fu Cai , Xiao-Han Ma , Misao Sasaki , Dong-Gang Wang , Zihan Zhou

Although the spectrum of primordial fluctuations has been accurately measured on scales above $\sim 0.1~\rm{Mpc}$, only upper limits exist on smaller scales. In this study, we investigate generic monochromatic enhancements to the…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-21 Guillermo Franco Abellán , Gaétan Facchinetti

Local-type primordial non-gaussianity generates a distinctive term in the clustering of tracers of large-scale structure, behaving as $k^{-2}$ at small wavenumbers $k$. In order to use this signal in a sample of galaxies to measure the…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-28 Neal Dalal , Will J. Percival

We investigate the evolution of the skewness of the distribution of density fluctuations in CDM models with both Gaussian and non--Gaussian initial fluctuations. We show that the method proposed by Coles \& Frenk (1991), which uses the…

Astrophysics · Physics 2015-06-24 P. Coles , L. Moscardini , F. Lucchin , S. Matarrese , A. Messina

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}.…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-19 Laura Marian , Stefan Hilbert , Robert E. Smith , Peter Schneider , Vincent Desjacques

We perturbatively study the effect of non-Gaussianities on the mass fraction of primordial black holes (PBHs) at the time of formation by systematically taking its effect into account in the one-point probability distribution function of…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-02 Takahiko Matsubara , Misao Sasaki