# Morphology of the Galaxy Distribution from Wavelet Denoising

@article{Martnez2005MorphologyOT, title={Morphology of the Galaxy Distribution from Wavelet Denoising}, author={V. J. Mart{\'i}nez and J-L. Starck and E. Saar and David L. Donoho and Simon C. Reynolds and Pablo de la Cruz and Silvestre Paredes}, journal={The Astrophysical Journal}, year={2005}, volume={634}, pages={744 - 755} }

We have developed a method based on wavelets to obtain the true underlying smooth density from a point distribution. The goal has been to reconstruct the density field in an optimal way, ensuring that the morphology of the reconstructed field reflects the true underlying morphology of the point field, which, as the galaxy distribution, has a genuinely multiscale structure, with near-singular behavior on sheets, filaments, and hot spots. If the discrete distributions are smoothed using Gaussian…

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## References

SHOWING 1-10 OF 44 REFERENCES

Wavelet analysis of the multifractal character of the galaxy distribution

- Physics
- 1993

We have determined generalized dimensions of the observed distribution of galaxies. Their different values indicate that this distribution may be described as a multifractal. In order to analyse this…

Analysis of the Spatial Distribution of Galaxies by Multiscale Methods

- PhysicsEURASIP J. Adv. Signal Process.
- 2005

It is shown that statistical properties of transform coefficients measure in a coherent and statistically reliable way, the degree of clustering, filamentarity, sheetedness, and voidedness of a data set.

Nonparametric Estimation of Intensity Maps Using Haar Wavelets and Poisson Noise Characteristics

- Mathematics
- 2000

We present a method for the nonparametric (model-free) estimation of an intensity map underlying two-dimensional count data with Poisson noise characteristics. Specifically, we extend the so-called…

Structure Detection in Low Intensity X-Ray Images using the Wavelet Transfor M Applied to Galaxy Cluster Cores Analysis

- Physics
- 1997

In the context of assessing and characterizing structures in X-ray images, we compare different approaches. Most often the intensity level is very low and necessitates a special treatment of Poisson…

Objective Detection of Voids and High-Density Structures in the First CfA Redshift Survey Slice

- Physics
- 1993

Voids of galaxies delineated by sharp one- or two-dimensional structures are the main features of the large-scale clustering of galaxies. In order to objectively identify the significant structures…

The topology of the large-scale structure of the universe

- Physics
- 1986

It has been suggested recently that the topology of a distribution of galaxies can be characterized by the mean Gaussian curvature per unit volume of surfaces of constant density. An expression is…

Beyond Genus Statistics: A Unifying Approach to the Morphology of Cosmic Structure

- Mathematics
- 1997

The genus statistics of isodensity contours has become a well-established tool in cosmology. In this Letter we place the genus in the wider framework of a complete family of morphological…

The 2dF Galaxy Redshift Survey : higher-order galaxy correlation functions

- Physics
- 2004

We measure moments of the galaxy count probability distribution function in the Two-degree Field Galaxy Redshift Survey (2dFGRS). The survey is divided into volume-limited subsamples in order to…

Quantifying the topology of large-scale structure

- Physics
- 1996

We propose and investigate a new algorithm for quantifying the topological properties of cosmological density fluctuations. We first motivate this algorithm by drawing a formal distinction between…

The 2dF Galaxy Redshift Survey: hierarchical galaxy clustering

- Physics
- 2004

We use the Two-Degree Field Galaxy Redshift Survey (2dFGRS) to test the hierarchical scaling hypothesis: namely, that the p-point galaxy correlation functions can be written in terms of the two-point…