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Title: ELUCID—Exploring the Local Universe with the reConstructed Initial Density Field. II. Reconstruction Diagnostics, Applied to Numerical Halo Catalogs

Abstract

The ELUCID project aims to build a series of realistic cosmological simulations that reproduce the spatial and mass distributions of the galaxies as observed in the Sloan Digital Sky Survey. This requires powerful reconstruction techniques to create constrained initial conditions (ICs). We test the reconstruction method by applying it to several N -body simulations. We use two medium-resolution simulations, which each produced three additional constrained N -body simulations. We compare the resulting friend-of-friend catalogs by using the particle indexes as tracers, and quantify the quality of the reconstruction by varying the main smoothing parameter. The cross-identification method we use proves to be efficient, and the results suggest that the most massive reconstructed halos are effectively traced from the same Lagrangian regions in the ICs. A preliminary time-dependence analysis indicates that high-mass-end halos converge only at a redshift close to the reconstruction redshift. This suggests that, for earlier snapshots, only collections of progenitors may be effectively cross-identified.

Authors:
; ; ;  [1];  [2];  [3];  [4];  [5]
  1. Center for Astronomy and Astrophysics, Shanghai Jiao Tong University, Shanghai 200240 (China)
  2. Key Laboratory for Research in Galaxies and Cosmology, Department of Astronomy, University of Science and Technology of China, Hefei, Anhui 230026 (China)
  3. Departamento de Física Teórica, Módulo 15, Facultad de Ciencias, Universidad Autónoma de Madrid, E-28049 Madrid (Spain)
  4. Shanghai Astronomical Observatory, Nandan Road 80, Shanghai 200030 (China)
  5. Department of Astronomy, University of Massachusetts, Amherst MA, 01003-9305 (United States)
Publication Date:
OSTI Identifier:
22663577
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 841; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CATALOGS; COMPARATIVE EVALUATIONS; DENSITY; GALAXIES; LAGRANGIAN FUNCTION; MANY-BODY PROBLEM; MASS; MASS DISTRIBUTION; RED SHIFT; RESOLUTION; SIMULATION; TIME DEPENDENCE; UNIVERSE

Citation Formats

Tweed, Dylan, Yang, Xiaohu, Li, Shijie, Jing, Y. P., Wang, Huiyuan, Cui, Weiguang, Zhang, Youcai, and Mo, H. J., E-mail: dtweed@sjtu.edu.cn. ELUCID—Exploring the Local Universe with the reConstructed Initial Density Field. II. Reconstruction Diagnostics, Applied to Numerical Halo Catalogs. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA6BF8.
Tweed, Dylan, Yang, Xiaohu, Li, Shijie, Jing, Y. P., Wang, Huiyuan, Cui, Weiguang, Zhang, Youcai, & Mo, H. J., E-mail: dtweed@sjtu.edu.cn. ELUCID—Exploring the Local Universe with the reConstructed Initial Density Field. II. Reconstruction Diagnostics, Applied to Numerical Halo Catalogs. United States. doi:10.3847/1538-4357/AA6BF8.
Tweed, Dylan, Yang, Xiaohu, Li, Shijie, Jing, Y. P., Wang, Huiyuan, Cui, Weiguang, Zhang, Youcai, and Mo, H. J., E-mail: dtweed@sjtu.edu.cn. Sat . "ELUCID—Exploring the Local Universe with the reConstructed Initial Density Field. II. Reconstruction Diagnostics, Applied to Numerical Halo Catalogs". United States. doi:10.3847/1538-4357/AA6BF8.
@article{osti_22663577,
title = {ELUCID—Exploring the Local Universe with the reConstructed Initial Density Field. II. Reconstruction Diagnostics, Applied to Numerical Halo Catalogs},
author = {Tweed, Dylan and Yang, Xiaohu and Li, Shijie and Jing, Y. P. and Wang, Huiyuan and Cui, Weiguang and Zhang, Youcai and Mo, H. J., E-mail: dtweed@sjtu.edu.cn},
abstractNote = {The ELUCID project aims to build a series of realistic cosmological simulations that reproduce the spatial and mass distributions of the galaxies as observed in the Sloan Digital Sky Survey. This requires powerful reconstruction techniques to create constrained initial conditions (ICs). We test the reconstruction method by applying it to several N -body simulations. We use two medium-resolution simulations, which each produced three additional constrained N -body simulations. We compare the resulting friend-of-friend catalogs by using the particle indexes as tracers, and quantify the quality of the reconstruction by varying the main smoothing parameter. The cross-identification method we use proves to be efficient, and the results suggest that the most massive reconstructed halos are effectively traced from the same Lagrangian regions in the ICs. A preliminary time-dependence analysis indicates that high-mass-end halos converge only at a redshift close to the reconstruction redshift. This suggests that, for earlier snapshots, only collections of progenitors may be effectively cross-identified.},
doi = {10.3847/1538-4357/AA6BF8},
journal = {Astrophysical Journal},
number = 1,
volume = 841,
place = {United States},
year = {Sat May 20 00:00:00 EDT 2017},
month = {Sat May 20 00:00:00 EDT 2017}
}
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