title: Signatures of the Primordial Universe from Its Emptiness: Measurement of Baryon Acoustic Oscillations from Minima of the Density Field.
abstract: Sound waves from the primordial fluctuations of the Universe imprinted in the large-scale structure, called baryon acoustic oscillations (BAOs), can be used as standard rulers to measure the scale of the Universe. These oscillations have already been detected in the distribution of galaxies. Here we propose to measure BAOs from the troughs (minima) of the density field. Based on two sets of accurate mock halo catalogues with and without BAOs in the seed initial conditions, we demonstrate that the BAO signal cannot be obtained from the clustering of classical disjoint voids, but it is clearly detected from overlapping voids. The latter represent an estimate of all troughs of the density field. We compute them from the empty circumsphere centers constrained by tetrahedra of galaxies using Delaunay triangulation. Our theoretical models based on an unprecedented large set of detailed simulated void catalogues are remarkably well confirmed by observational data. We use the largest recently publicly available sample of luminous red galaxies from SDSS-III BOSS DR11 to unveil for the first time a >3σ BAO detection from voids in observations. Since voids are nearly isotropically expanding regions, their centers represent the most quiet places in the Universe, keeping in mind the cosmos origin and providing a new promising window in the analysis of the cosmological large-scale structure from galaxy surveys.
authors.affiliation: Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam, Germany.
authors.forename: Francisco-Shu
authors.initials: FS
authors.lastname: Kitaura
authors.affiliation: Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam, Germany.
authors.forename: Chia-Hsun
authors.initials: CH
authors.lastname: Chuang
authors.affiliation: Tsinghua Center of Astrophysics and Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liang
authors.affiliation: Tsinghua Center of Astrophysics and Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Tsinghua Center of Astrophysics and Department of Physics, Tsinghua University, Beijing 100084, China.|Aix-Marseille Université, CNRS/IN2P3, CPPM UMR 7346, 13288 Marseille, France.
authors.forename: Charling
authors.initials: C
authors.lastname: Tao
authors.affiliation: Instituto de Física Teórica, (UAM/CSIC), Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain.|Campus of International Excellence UAM+CSIC, Cantoblanco, E-28049 Madrid, Spain.|Departamento de Fısica Teórica M8, Universidad Autonoma de Madrid (UAM), Cantoblanco, E-28049, Madrid, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Rodríguez-Torres
authors.affiliation: Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Eisenstein
authors.affiliation: Sorbonne Universits, Institut Lagrange de Paris (ILP), 98 bis Boulevard Arago, 75014 Paris, France.|Laboratoire de Physique Nuclaire et de Hautes Energies, Université Pierre et Marie Curie, 4 Place Jussieu, Tour 22, 1er tage, 75005 Paris, France.
authors.forename: Héctor
authors.initials: H
authors.lastname: Gil-Marín
authors.affiliation: Laboratoire dAstrophysique, Ecole Polytechnique Fedérale de Lausanne, CH-1015 Lausanne, Switzerland.|Aix Marseille Université, CNRS, LAM (Laboratoire dAstrophysique de Marseille) UMR 7326, F-13388, Marseille, France.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Kneib
authors.affiliation: Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Cameron
authors.initials: C
authors.lastname: McBride
authors.affiliation: Institute of Cosmology & Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth PO1 3FX, United Kingdom.
authors.forename: Will J
authors.initials: WJ
authors.lastname: Percival
authors.affiliation: Institute of Cosmology & Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth PO1 3FX, United Kingdom.|Center for Cosmology and AstroParticle Physics, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Ashley J
authors.initials: AJ
authors.lastname: Ross
authors.affiliation: Max-Planck-Institut für Extraterrestrische Physik, Postfach 1312, Giessenbachstraße, 85741 Garching, Germany.
authors.forename: Ariel G
authors.initials: AG
authors.lastname: Sánchez
authors.affiliation: Center for Cosmology and Particle Physics, New York University, 4 Washington Place, New York, New York 10003, USA.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Tinker
authors.affiliation: University of St. Andrews, North Haugh, St. Andrews Fife, KY16 9SS, United Kingdom.
authors.forename: Rita
authors.initials: R
authors.lastname: Tojeiro
authors.affiliation: Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20-364, México.
authors.forename: Mariana
authors.initials: M
authors.lastname: Vargas-Magana
authors.affiliation: Institute of Cosmology & Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth PO1 3FX, United Kingdom.|National Astronomy Observatories, Chinese Academy of Science, Beijing, 100012, People's Republic of China.
authors.forename: Gong-Bo
authors.initials: GB
authors.lastname: Zhao