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arXiv · 1509.05040

Unmasking the Masked Universe: the 2M++ catalogue through Bayesian eyes

Guilhem Lavaux·Jens Jasche
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Abstract

This work describes a full Bayesian analysis of the Nearby Universe as traced by galaxies of the 2M++ survey. The analysis is run in two sequential steps. The first step self-consistently derives the luminosity dependent galaxy biases, the power-spectrum of matter fluctuations and matter density fields within a Gaussian statistic approximation. The second step makes a detailed analysis of the three dimensional Large Scale Structures, assuming a fixed bias model and a fixed cosmology. This second step allows for the reconstruction of both the final density field and the initial conditions at z=1000 assuming a fixed bias model. From these, we derive fields that self-consistently extrapolate the observed large scale structures. We give two examples of these extrapolation and their utility for the detection of structures: the visibility of the Sloan Great Wall, and the detection and characterization of the Local Void using DIVA, a Lagrangian based technique to classify structures.

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Guilhem Lavaux, Jens Jasche. 2015-12-08. Unmasking the Masked Universe: the 2M++ catalogue through Bayesian eyes. https://doi.org/10.1093/mnras%2Fstv2499

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