Excursion sets and non-Gaussian void statistics

Journal Article · Sat Jan 15 04:00:00 EST 2011 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.83.023521· OSTI ID:21503942

D'Amico, Guido ^[1]; INFN-Sezione di Trieste, 34151 Trieste ^[2]; Musso, Marcello; Paranjape, Aseem ^[3]; Norena, Jorge ^[4]; INFN-Sezione di Trieste, 34151 Trieste ^[2]

---

1. Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, New York 10003 (United States)
2. Italy
3. Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, 34151, Trieste (Italy)
4. Institut de Ciencies del Cosmos (ICC), Universitat de Barcelona (IEEC-UB), Marti Franques 1, E08028 Barcelona (Spain)

Primordial non-Gaussianity (NG) affects the large scale structure (LSS) of the Universe by leaving an imprint on the distribution of matter at late times. Much attention has been focused on using the distribution of collapsed objects (i.e. dark matter halos and the galaxies and galaxy clusters that reside in them) to probe primordial NG. An equally interesting and complementary probe however is the abundance of extended underdense regions or voids in the LSS. The calculation of the abundance of voids using the excursion set formalism in the presence of primordial NG is subject to the same technical issues as the one for halos, which were discussed e.g. in Ref. [51][G. D'Amico, M. Musso, J. Norena, and A. Paranjape, arXiv:1005.1203.]. However, unlike the excursion set problem for halos which involved random walks in the presence of one barrier {delta}{sub c}, the void excursion set problem involves two barriers {delta}{sub v} and {delta}{sub c}. This leads to a new complication introduced by what is called the 'void-in-cloud' effect discussed in the literature, which is unique to the case of voids. We explore a path integral approach which allows us to carefully account for all these issues, leading to a rigorous derivation of the effects of primordial NG on void abundances. The void-in-cloud issue, in particular, makes the calculation conceptually rather different from the one for halos. However, we show that its final effect can be described by a simple yet accurate approximation. Our final void abundance function is valid on larger scales than the expressions of other authors, while being broadly in agreement with those expressions on smaller scales.

• OSTI ID: 21503942
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 2 Vol. 83; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ACCIDENTS
APPROXIMATIONS
CALCULATION METHODS
DISTRIBUTION
EXCURSIONS
GALAXIES
GALAXY CLUSTERS
GRAPH THEORY
MATHEMATICS
MATTER
NONLUMINOUS MATTER
RANDOMNESS
REACTOR ACCIDENTS
STATISTICS
UNIVERSE
VOIDS