□ 연구개요 Big Data challenges are the next frontier in cosmological research, as state-of-the-art astronomical surveys (SDSS, DESI, LSST) are or will be soon providing enormous 3D atlases of galaxies and quasars by mapping increasingly larger volumes of the Universe. These unique datasets allow one to address pressing scientific open questions, such as the nature of the accelerated expansion of the Universe (i.e. Dark Energy), the rate of growth of structures, the summed neutrino mass, and Primordial non-Gaussianity (PNG) in the density field. The massive sample size along with the high dimensionality of Big Data introduce computational and statistical challenges: their interpretation requires the ability to simulate larger and larger volumes of the Universe with exquisite resolution over a wide range of scales, the modeling of additional components besides gas and dark matter, as well as fast analysis techniques and smart algorithms. To this end, high-resolution and high-fidelity cosmological simulations and cutting-edge mock catalogs, particularly in presence of massive neutrinos and dark radiation, are essential in order to interpret massive cosmic web data and control systematics. At the present time, there is a pressing demand for state-of-the-art cosmological simulations and mocks, especially including the effects of massive neutrinos at small scales. Our research is precisely filling this gap, providing key deliverables to advance our knowledge of the cosmos. □ 연구 목표대비 연구결과 The major goals of our proposal are to provide novel cosmological hydrodynamical simulations and state-of-the-art mock catalogs built from the largest simulation ever made (Outer Rim), and use those products in synergy with Sloan Digital Sky Survey (SDSS) data to map uncharted regions of the cosmic web with different large-scale structure (LSS) tracers - with a major focus on dark energy, neutrino cosmology, and PNG. The Sejong Suite, an extensive collection of over 300 state-of-the-art high-resolution cosmological hydrodynamical simulations primarily developed for modeling the Lyman-Alpha forest, has been designed for this purpose. Developed at KISTI, the suite spans a variety of cosmological and astrophysical parameters, including the dark sector; it is available to the scientific community, and represents a valuable asset for surveys such as eBOSS and DESI. In addition, we deliver a large number of Outer Rim state-of-the-art mock catalogs. These mocks have been used for the eBOSS challenge functional to the final analysis of the eBOSS DR16 galaxy sample. Outperforming with respect to our initial goals, in July 2020 we released a comprehensive analysis of the largest 3D map of the Universe ever created, filling the most significant gaps in our possible exploration of the Universe. Such results were presented in more than 20 papers, along with the most accurate constraints on cosmological parameters and neutrino mass to date. Our mock products were used in the eBOSS DR16 consensus cosmology, to quantify the global systematic error budget. We also released one of the most stringent bounds on PNG of the local type ever obtained from LSS data. □ 연구개발결과의 중요성 High-fidelity cosmological simulations and mocks, particularly including massive neutrinos and dark radiation, are essential for interpreting cosmological data. And smart algorithms are necessary for dealing with massive datases, such as those obtained by large-volume cosmological surveys. Moreover, our primary scientific goals (i.e. neutrino cosmology, the dark sector, and PNG) are at the forefront of contemporary research. In particular, ruling out one of the neutrino hierarchies would have a dramatic impact in particle physics, as its knowledge will complete the understanding of the neutrino sector and shed light into leptogenesis, baryogenesis, and the origin of mass. Finally, the release of the largest 3D map of the Universe ever created by the eBOSS collaboration marks a remarkable milestone, with numerous press releases worldwide. Such challenging achievement, made available to the scientific community, represents a legacy in astronomy, and a pathfinder for all of the next generation large-volume surveys (DESI, LSST, GMT). (출처 : 연구결과 요약문 2p)
- 연구책임자 : Graziano Rossi
- 주관연구기관 : 세종대학교
- 발행년도 : 20201200
- Keyword : Simulations;Large-Volume Surveys;Large-Scale Structure;Neutrinos;Cosmology;Computational Methods;Dark Matter;Dark Energy;Big Data/Smart Algorithms;