The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: mock galaxy catalogues for the BOSS Final Data Release (1509.06400v3)

Abstract: We reproduce the galaxy clustering catalogue from the SDSS-III Baryon Oscillation Spectroscopic Survey Final Data Release (BOSS DR11&DR12) with high fidelity on all relevant scales in order to allow a robust analysis of baryon acoustic oscillations and redshift space distortions. We have generated (6,000) 12,288 MultiDark PATCHY BOSS (DR11) DR12 light-cones corresponding to an effective volume of $\sim192,000\,[h^{-1}\,{\rm Gpc}]^3$ (the largest ever simulated volume), including cosmic evolution in the redshift range from 0.15 to 0.75. The mocks have been calibrated using a reference galaxy catalogue based on the halo abundance matching modelling of the BOSS DR11&DR12 galaxy clustering data and on the data themselves. The production follows three steps. First, we apply the PATCHY code to generate a dark matter field and an object distribution including nonlinear stochastic galaxy bias. Secondly, we run the halo/stellar distribution reconstruction HADRON code to assign masses to the various objects. This step uses the mass distribution as a function of local density and non-local indicators (i.e., tidal field tensor eigenvalues and relative halo exclusion separation for massive objects) from the reference simulation applied to the corresponding PATCHY dark matter and galaxy distribution. Finally, we apply the SUGAR code to build the light cones. The resulting MultiDark PATCHY mock light cones reproduce the number density, selection function, survey geometry, and in general within 1 $\sigma$, for arbitrary stellar mass bins, the power spectrum up to $k=0.3\,h\,{\rm Mpc}^{-1}$, the two-point correlation functions down to a few Mpc scales, and the three-point statistics of the BOSS DR11&DR12 galaxy samples.

• The paper presents 12,288 MultiDark patchy mock light-cones calibrated via halo abundance matching to accurately simulate galaxy clustering in the SDSS-III BOSS survey.
• Their methodology reproduces key clustering statistics, including the power spectrum (up to k = 0.3h/Mpc) and correlation functions, ensuring strong fidelity with observed data.
• The study effectively addresses observational biases and redshift space distortions, offering robust statistical tools for analyzing baryon acoustic oscillations and large-scale structure.

Analysis of Galaxy Clustering in SDSS-III BOSS Using MultiDark Patchy Mock Catalogues

The paper under review presents an extensive paper on the clustering of galaxies within the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS) Final Data Release through the application of MultiDark patchy mock catalogues. The research primarily focuses on accurately simulating the large-scale structure of the Universe by modeling galaxy distributions and redshift space distortions across an expansive cosmic volume.

The authors generated an unprecedented volume of 12,288 light-cones using MultiDark patchy mocks, covering nearly 192,000 cubic gigaparsecs. Importantly, these simulations were calibrated against the BOSS DR11 and DR12 galaxy distributions using the halo abundance matching (HAM) approach. Notably, their mock catalogues incorporate enhancements to capture redshift evolution, including both bias evolution and nonlinear stochastic galaxy bias modeling.

Crucially, their methodology achieved high fidelity with observational data in terms of number density, selection functions, survey geometry, and statistical measures including the power spectrum up to scales of $k = 0.3h\,\text{Mpc}^{-1}$, the two-point correlation functions, and three-point statistics. This was accomplished by implementing a multi-step process, comprising of generating reference catalogues via simulations, calibrating the patchy code for bias modeling, reconstructing halo/stellar distributions, and finalizing the light cones using the survey generator "sugar."

In the context of broader cosmological research, these mock catalogues provide critical insights and robust statistical tools for interpreting BOSS data, particularly in evaluating baryon acoustic oscillations (BAOs) and redshift space distortions (RSDs). This paper is significant for its capacity to address uncertainties in large-scale structure analyses and systematically account for observational biases.

For future developments, the paper illuminates the potential necessity of incorporating more sophisticated models to simulate structure formation, particularly for upcoming surveys targeting different galaxy populations, like emission line galaxies. The incorporation of nonlocal bias modeling during the full galaxy population replication could further advance the fidelity of galaxy mock catalogues.

Overall, this paper substantially contributes to our understanding of the Universe's large-scale structure and provides a foundational framework for analyzing large cosmological datasets. It highlights the evolving relationship between observational cosmology and computational simulations, underscoring the necessity of continually refining modeling techniques to match observational advancements.