DOCSLIB.ORG

Reconciling the Diversity and Uniformity of Galactic Rotation Curves with Self-Interacting Dark Matter

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Reconciling the Diversity and Uniformity of Galactic Rotation Curves with Self-Interacting Dark Matter PHYSICAL REVIEW X 9, 031020 (2019) Reconciling the Diversity and Uniformity of Galactic Rotation Curves with Self-Interacting Dark Matter † Tao Ren,1 Anna Kwa,2 Manoj Kaplinghat,2,* and Hai-Bo Yu1, 1Department of Physics and Astronomy, University of California, Riverside, California 92521, USA 2Department of Physics and Astronomy, University of California, Irvine, California 92697, USA (Received 23 October 2018; revised manuscript received 25 April 2019; published 7 August 2019) Galactic rotation curves exhibit diverse behavior in the inner regions while obeying an organizing principle; i.e., they can be approximately described by a radial acceleration relation or the modified Newtonian dynamics phenomenology. We analyze the rotation curve data from the SPARC sample and explicitly demonstrate that both the diversity and uniformity are naturally reproduced in a hierarchical structure formation model with the addition of dark matter self-interactions. The required concentrations of the dark matter halos are fully consistent with the concentration-mass relation predicted by the Planck cosmological model. The inferred stellar mass-to-light (3.6 μm) ratios scatter around 0.5 M⊙=L⊙,as expected from population synthesis models, leading to a tight radial acceleration relation and a baryonic Tully-Fisher relation. The inferred stellar-halo mass relation is consistent with the expectations from abundance matching. These results provide compelling arguments in favor of the idea that the inner halos of galaxies are thermalized due to dark matter self-interactions. DOI: 10.1103/PhysRevX.9.031020 Subject Areas: Astrophysics, Cosmology ϒ ¼ 0 5 I. INTRODUCTION constant stellar mass-to-light ratio ⋆;disk . M⊙=L⊙ and ϒ⋆ ¼ 0.7 M⊙=L⊙ in the 3.6-μm band. The scatter Galactic rotation curves of spiral galaxies show a variety ;bulge of behaviors in the inner parts, even across systems with in this radial acceleration relation (RAR) is around similar halo and stellar masses, which lacks a self-con- 0.1 dex, and the tightness of this relation has been sistent explanation in the standard cold dark matter (CDM) interpreted as a signature of MOND [19]. model [1–13]. Along with this diversity, a long-standing It has long been argued that the acceleration scale observation is that many rotation curves can be understood (including the cH0 dependence) can emerge from hierar- in terms of modified Newtonian dynamics (MOND) chical structure formation predicted in CDM [20,21]. phenomenology [14,15] (see Ref. [16] for a review); Recent hydrodynamical simulations of galaxy formation i.e., there exists a characteristic gravitational acceleration with CDM have clearly shown that a RAR emerges −10 2 [22–24]. However, these simulated galaxies do not re- scale, g† ≈ 10 m=s ∼ cH0=7, with H0 being the present Hubble expansion rate, below which the observed present the full range of diversity in the SPARC data set, pffiffiffiffiffiffiffiffiffiffiffiffi and they cannot yet explain the rotation curves of low- and acceleration can be approximated as g†g , with g bar bar high-surface-brightness galaxies simultaneously. being the baryonic acceleration (a.k.a. Milgrom’slaw). In this paper, we show that self-interacting dark matter More recently, McGaugh et al. [17] analyzed the Spitzer (SIDM) provides a unified way to understand the diverse Photometry and Accurate Rotation Curves (SPARC) data rotation curves of spiral galaxies while reproducing set [18] and showed that there is a tight relation between the RAR with a small scatter. We analyze the SPARC the total gravitational acceleration at any radius and the data set based on the SIDM halo model proposed in acceleration contributed by the baryons, assuming a Refs. [25,26] and demonstrate three key observations leading to this result. σ ∼ 1 2 *Corresponding author. (i) For cross section per unit mass =m cm =g, [email protected] dark matter self-interactions thermalize the inner † Corresponding author. regions at distances less than about 10% of the virial [email protected] radius of galactic halos, while the outer regions remain unchanged. Thus, SIDM inherits essential Published by the American Physical Society under the terms of features of the ΛCDM hierarchical structure for- the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to mation model such as the halo concentration-mass the author(s) and the published article’s title, journal citation, relation, which sets the characteristic acceleration and DOI. scale of halos. 2160-3308=19=9(3)=031020(12) 031020-1 Published by the American Physical Society REN, KWA, KAPLINGHAT, and YU PHYS. REV. X 9, 031020 (2019) (ii) In the inner halo, thermalization ties dark matter and We match this isothermal profile to a Navarro-Frenk- baryon distributions together [25,27,28], and the White (NFW) form [33,34] at r1, where a dark matter SIDM halo can naturally accommodate the diverse particle has scattered Oð1Þ timesovertheageofthe range of “cored” and “cusped” central density pro- galaxy, assuming continuity in both the density and the files, depending on how the baryons are distributed. enclosed mass at r1.Inthisway,theisothermal ρ σ Combined with the scatter in the concentration-mass parameters ( 0, v0) directly map onto the NFW param- ρ relation, this provides the diversity required to ex- eters (rs, s)or(rmax, Vmax). This model provides an plain the rotation curves [26,29,30]. approximate way to calculate the SIDM distribution in a (iii) For the same σ=m that addresses the diversity halo if its CDM counterpart is known, and vice versa. It problem, the baryon content of the galaxies and correctly predicts the halo central density and its the mass model of their host halos also lead to the scalings with the outer halo properties, stellar profiles, RAR with a scatter as small as the one in Ref. [17].In andcrosssection,asconfirmedinbothisolatedand ϒ our SIDM fits, the inferred stellar ⋆;disk values for cosmological N-body simulations with and without individual galaxies have a distribution peaked toward baryons; see, e.g., Refs. [26,28,30,35,36].Seethe 0.5 M⊙=L⊙, as expected from stellar population Appendix and the Supplemental Material [32] for a synthesis models [31]. detailed description of the model and additional com- The rest of the paper is organized as follows. In parisons between model predictions and cosmological Sec. II, we present the SIDM fits to 135 galaxies from simulations. the SPARC sample, which exemplify the full range of We adopt two independent but complementary the diversity. In Sec. III, we show the radial acceleration approaches to perform the analysis. In the controlled relation and the distribution of the stellar mass-to-light sampling (CS) approach, we demand that the host halos ratios from our SIDM fits, compared to the MOND fits. follow the concentration-mass relation within a 2σ range In Sec. IV, we discuss the host halo properties and the predicted in cosmological simulations [37]. We model the origin of the acceleration scale. In Sec. V,weshowthe stellar distribution as an axisymmetric thin disk as in predicted stellar-halo mass relation and the baryonic Ref. [29], which directly enters into the calculation of Tully-Fisher relation (BTFR). We comment on future the density profile of SIDM through the gravitational directions and conclude in Sec. VI. In the Appendix, we potential ΦðR; zÞ. In the CS fits, we start with the outer provide detailed information about the model and the NFW halo and find the SIDM density profile that matches fitting procedure. In the Supplemental Material [32],we its mass and density at r1. In the second approach, we use present SIDM and MOND fits to 135 individual galaxies the Markov chain Monte Carlo (MCMC) sampling (MS) to from the SPARC sample and additional results that explore the full likelihood. To save computational time, we support the main text, including model fits to simulated assume spherical symmetry by spreading the mass within halos. the disk at radius R into a sphere of the same radius [25,28]. The rotation curves generated from two approaches II. THE DIVERSITY OF GALACTIC agree well, and the differences in the fits are small (see ROTATION CURVES Supplemental Material [32]). For our main results, we show inferences from both of the approaches. We select 135 out of 175 galaxies in the full SPARC In Fig. 1, we show the SIDM fits to the diverse rotation sample based on the criteria that they must have a curves from the controlled sampling with σ=m ¼ 3 cm2=g. recorded value for the flat part of the rotation curve, Vf . In each panel, galaxies are selected to have similar flat In our sample, 87, 42, and 6 galaxies have quality rotation velocities at their outermost data points. The rise up flags 1, 2, and 3, respectively. It spans a wide range to Vf within their central regions displays a wide variety of of galaxy masses and inner shapes of rotation curves slopes, and the SIDM halo model provides equally good 20 300 with Vf ranging from km=sto km=s. In fitting fits to the shallow and steeply rising rotation curves. The to the data, we utilize the analytical SIDM halo fits for the other galaxies in the sample are as good as those model [26,29], where we assume the dark matter in Fig. 1 (see Supplemental Material [32]). distribution in the inner halo follows the isothermal The success of the SIDM halo model stems from a density profile, combination of the following effects. First, SIDM thermal- ization ties the baryon and dark matter distributions together. ρ ð Þ¼ρ (½Φ ð0 0Þ − Φ ð Þ σ2 ) ð Þ iso R; z 0 exp tot ; tot R; z = v0 ; 1 For low-surface-brightness galaxies, thermalization leads to a shallow density core and a circular velocity profile that ρ σ – where 0 is the central dark matter density, v0 is the rises mildly with radius [38 44].
Load more

Recommended publications
  • Small Scale Problems of the CDM Model
    galaxies Article Small Scale Problems of the LCDM Model: A Short Review Antonino Del Popolo 1,2,3,* and Morgan Le Delliou 4,5,6 1 Dipartimento di Fisica e Astronomia, University of Catania , Viale Andrea Doria 6, 95125 Catania, Italy 2 INFN Sezione di Catania, Via S. Sofia 64, I-95123 Catania, Italy 3 International Institute of Physics, Universidade Federal do Rio Grande do Norte, 59012-970 Natal, Brazil 4 Instituto de Física Teorica, Universidade Estadual de São Paulo (IFT-UNESP), Rua Dr. Bento Teobaldo Ferraz 271, Bloco 2 - Barra Funda, 01140-070 São Paulo, SP Brazil; [email protected] 5 Institute of Theoretical Physics Physics Department, Lanzhou University No. 222, South Tianshui Road, Lanzhou 730000, Gansu, China 6 Instituto de Astrofísica e Ciências do Espaço, Universidade de Lisboa, Faculdade de Ciências, Ed. C8, Campo Grande, 1769-016 Lisboa, Portugal † [email protected] Academic Editors: Jose Gaite and Antonaldo Diaferio Received: 30 May 2016; Accepted: 9 December 2016; Published: 16 February 2017 Abstract: The LCDM model, or concordance cosmology, as it is often called, is a paradigm at its maturity. It is clearly able to describe the universe at large scale, even if some issues remain open, such as the cosmological constant problem, the small-scale problems in galaxy formation, or the unexplained anomalies in the CMB. LCDM clearly shows difficulty at small scales, which could be related to our scant understanding, from the nature of dark matter to that of gravity; or to the role of baryon physics, which is not well understood and implemented in simulation codes or in semi-analytic models.
    [Show full text]
  • Cosmological and Astrophysical Structures in the Einstein-De Sitter Universe
    Cosmological and astrophysical structures in the Einstein-de Sitter universe A Thesis Submitted to the Faculty of Sciences of Universidad de los Andes In Partial Fulfillment of the Requirements For the Degree of Master of Sciences-Physics by Andres´ Balaguera Antol´ınez Bogot´a D.C Colombia 2006 Universidad de los Andes Cosmological and astrophysical structures in the Einstein-de Sitter universe A thesis submitted to the Faculty of Sciences of Universidad de los Andes In Partial Fulfillment of the Requirements For the Degree of Master of Sciences-Physics c Copyright All rights reserved by Andr´es Balaguera Antol´ınez Bogot´a D.C Colombia 2006 LATEX2006 La tesis escrita por Andres´ Balaguera Antol´ınez cumple con los requerimientos exigidos para aplicar al titulo de Maestr´ıa en Ciencias-F´ısica y ha sido aprobada por el profesor Marek Nowakowski Ph.D, como director y por los profesores Juan Manuel Tejeiro Ph.D. y Rolando Roldan,´ Ph.D., como evaluadores. Marek Nowakowski Ph.D., Director Universidad de los Andes Juan Manuel Tejeiro, Ph.D., Evaluador Universidad Nacional de Colombia Rolando Roldan,´ Ph.D., Evaluador Universidad de los Andes Cosmological and astrophysical structures in the Einstein-de Sitter universe Andr´es Balaguera Antol´ınez, Physicist Director: Marek Nowakowski Ph.D Abstract In this work we explore the consequences of a non zero cosmological constant on cosmological and as- trophysical structures. We find that the effects are associated to the density of the configurations as well as to the geometry. Homogeneous and spherical configurations are slightly affected. For non ho- mogeneous configurations, we calculate the effects on a polytropic configurations and on the isothermal sphere, making special emphasis on the fact that the cosmological constant sets certain scales of length, time, mass and density.
    [Show full text]
  • Relation Between the Turnaround Radius and Virial Mass in F(R) Model
    Prepared for submission to JCAP Relation between the Turnaround radius and virial mass in f(R) model Rafael C. C. Lopes,a;b Rodrigo Voivodic,a L. Raul Abramo,a Laerte Sodré Jrc aInstituto de Física, Universidade de São Paulo, Rua do Matão, 1371, São Paulo, SP 05508- 090, Brazil bInstituto Federal de Educação, Ciência e Tecnologia do Maranhão, Campus Santa Inês, BR-316, s/n, Santa Inês, MA 65304-770, Brazil cInstituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, Rua do Matão, 1226, São Paulo, SP 05508-090, Brazil E-mail: [email protected], [email protected], [email protected], [email protected] Abstract. We investigate the relationship between the turnaround radius Rt and the virial mass Mv of cosmic structures in the context of ΛCDM model and in an f(R) model of modified gravity – namely, the Hu-Sawicki model. The turnaround radius is the distance from the center of the cosmic structure to the shell that is detaching from the Hubble flow at a given time, while the virial mass is defined, for this work, as the mass enclosed within the volume where the density is 200 times the background density. We employ a new approach by considering that, on average, gravitationally bound astrophysical systems (e.g., galaxies, groups and clusters of galaxies) follow, in their innermost region, a Navarro-Frenk-White density profile, while beyond the virial radius (Rv) the profile is well approximated by the 2-halo term of the matter correlation function. By combining these two properties together with the information drawn from solving the spherical collapse for the structures, we are able to connect two observables that can be readily measured in cosmic structures: the turnaround radius and the virial mass.
    [Show full text]
  • The Stellar Mass Content of Groups and Clusters of Galaxies
    MNRAS 000, 000–000 (0000) Preprint 1 February 2018 Compiled using MNRAS LATEX style file v3.0 First results from the IllustrisTNG simulations: the stellar mass content of groups and clusters of galaxies Annalisa Pillepich1;2?, Dylan Nelson3, Lars Hernquist2, Volker Springel4;5, Rudiger¨ Pakmor4, Paul Torrey6y, Rainer Weinberger4, Shy Genel7;8, Jill P. Naiman2, Federico Marinacci6, and Mark Vogelsberger6z 1Max-Planck-Institut fur¨ Astronomie, Konigstuhl¨ 17, 69117 Heidelberg, Germany 2Harvard–Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 3Max-Planck-Institut fur¨ Astrophysik, Karl-Schwarzschild-Str. 1, 85741 Garching, Germany 4Heidelberg Institute for Theoretical Studies, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg, Germany 5Zentrum fur¨ Astronomie der Universitat¨ Heidelberg, ARI, Monchhofstr.¨ 12-14, D-69120 Heidelberg, Germany 6Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA 7Center for Computational Astrophysics, Flatiron Institute, 162 Fifth Avenue, New York, NY 10010, USA 8Columbia Astrophysics Laboratory, Columbia University, 550 West 120th Street, New York, NY 10027, USA 1 February 2018 ABSTRACT The IllustrisTNG project is a new suite of cosmological magneto-hydrodynamical simula- tions of galaxy formation performed with the AREPO code and updated models for feedback physics. Here we introduce the first two simulations of the series, TNG100 and TNG300, and quantify the stellar mass content of about 4000 massive galaxy groups and clusters 13 15 (10 6 M200c=M 6 10 ) at recent times (z 6 1). The richest clusters have half of their to- tal stellar mass bound to satellite galaxies, with the other half being associated with the central 14 galaxy and the diffuse intra-cluster light.
    [Show full text]
  • Dark Matter Heats up in Dwarf Galaxies
    MNRAS 000, 000{000 (0000) Preprint 15 April 2019 Compiled using MNRAS LATEX style file v3.0 Dark matter heats up in dwarf galaxies J. I. Read1?, M. G. Walker2, P. Steger3 1Department of Physics, University of Surrey, Guildford, GU2 7XH, UK 2McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, PA 15213, United States 3Institute for Astronomy, Department of Physics, ETH Z¨urich,Wolfgang-Pauli-Strasse 27, CH-8093 Z¨urich,Switzerland 15 April 2019 ABSTRACT Gravitational potential fluctuations driven by bursty star formation can kinematically `heat up' dark matter at the centres of dwarf galaxies. A key prediction of such models is that, at a fixed dark matter halo mass, dwarfs with a higher stellar mass will have a lower central dark matter density. We use stellar kinematics and HI gas rotation curves to infer the inner dark matter densities of eight dwarf spheroidal and eight dwarf irregular galaxies with a wide range of star formation histories. For all galaxies, we estimate the dark matter density at a common radius of 150 pc, ρDM(150 pc). We find that our sample of dwarfs falls into two distinct classes. Those that stopped 8 −3 forming stars over 6 Gyrs ago favour central densities ρDM(150 pc) > 10 M kpc , consistent with cold dark matter cusps, while those with more extended star formation 8 −3 favour ρDM(150 pc) < 10 M kpc , consistent with shallower dark matter cores. Using abundance matching to infer pre-infall halo masses, M200, we show that this dichotomy is in excellent agreement with models in which dark matter is heated up by bursty star formation.
    [Show full text]
  • Dark Matter Halo Mergers and Quasars
    University of Pennsylvania ScholarlyCommons Publicly Accessible Penn Dissertations Spring 2010 Dark Matter Halo Mergers and Quasars Jorge Moreno University of Pennsylvania, [email protected] Follow this and additional works at: https://repository.upenn.edu/edissertations Part of the Cosmology, Relativity, and Gravity Commons, and the External Galaxies Commons Recommended Citation Moreno, Jorge, "Dark Matter Halo Mergers and Quasars" (2010). Publicly Accessible Penn Dissertations. 177. https://repository.upenn.edu/edissertations/177 This paper is posted at ScholarlyCommons. https://repository.upenn.edu/edissertations/177 For more information, please contact [email protected]. Dark Matter Halo Mergers and Quasars Abstract The formation and evolution of galaxies and the supermassive black holes they harbor at their nuclei depends strongly on the merger history of their surrounding dark matter haloes. First we developed a semi-analytic algorithm that describes the merger history tree of a halo. The following tests were performed: the conditional mass function, the time and mass distributions at formation, and the time distribution of the last major merger. We provide a model for the creation rate of dark matter haloes, informed by both coagulation theory and the modified excursion set approach with moving barriers. A comparison with N-body simulations shows that our square-root barrier merger rate is significantly better than the standard extended Press-Schechter rate used in the literature. The last chapter is dedicated to a simple model of quasar activation by major mergers of dark matter haloes. The model consists of two main ingredients: the halo merger rate describing triggering, and a quasar light curve, which tracks the evolution of individual quasars.
    [Show full text]
  • Surface Term Effects on Mass Estimators M
    A&A 590, A58 (2016) Astronomy DOI: 10.1051/0004-6361/201527788 & c ESO 2016 Astrophysics Surface term effects on mass estimators M. Membrado1 and A. F. Pacheco2; 3 1 Departamento de Física Teórica, Universidad de Zaragoza, 50009 Zaragoza, Spain e-mail: [email protected] 2 Departamento de Física Teórica, Universidad de Zaragoza, 50009 Zaragoza, Spain 3 BIFI, Instituto de Biofísica y Física de Sistemas Complejos, Universidad de Zaragoza, 50009 Zaragoza, Spain e-mail: [email protected] Received 19 November 2015 / Accepted 26 February 2016 ABSTRACT Context. We propose a way of estimating the mass contained in the volume occupied by a sample of galaxies in a virialized system. Aims. We analyze the influence of surface effects and the contribution of the cosmological constant terms on our mass estimations of galaxy systems. Methods. We propose two equations that contain surface terms to estimate galaxy sample masses. When the surface terms are ne- glected, these equations provide the so-called virial and projected masses. Both equations lead to a single equation that allows sample masses to be estimated without the need for calculating surface terms. Sample masses for some nearest galaxy groups are estimated and compared with virialized masses determined from turn-around radii and results of a spherical infall model. Results. Surface effects have a considerable effect on the mass estimations of the studied galaxy groups. According to our results, they lead sample masses of some groups to being less than half the virial mass estimations and even less than 10% of projected mass estimations. However, the contributions of cosmological constant terms to mass estimations are smaller than 2% for the majority of the virialized groups studied.
    [Show full text]
  • A Dark Matter Profile to Model Diverse Feedback-Induced Core Sizes Of
    Mon. Not. R. Astron. Soc. 000,1{25 (2020) Printed 9 July 2020 (MN LATEX style file v2.2) A dark matter profile to model diverse feedback-induced core sizes of ΛCDM haloes Alexandres Lazar1?, James S. Bullock1, Michael Boylan-Kolchin2, T.K. Chan3;4, Philip F. Hopkins5, Andrew S. Graus2, Andrew Wetzel6, Kareem El-Badry7, Coral Wheeler4, Maria C. Straight8;2, Duˇsan Kereˇs4, Claude-Andr´eFaucher-Gigu`ere9, Alex Fitts2 and Shea Garrison-Kimmel5 1Department of Physics and Astronomy, University of California, Irvine, CA 92697 USA 2Department of Astronomy, The University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, Texas 78712-1205, USA 3Institute for Computational Cosmology, Durham University, South Road, Durham, DH1 3LE, UK 4Department of Physics, Center for Astrophysics and Space Science, University of California at San Diego, 9500 Gilman Dr. 5California Institute of Technology, TAPIR, Mailcode 350-17, Pasadena, CA 91125, USA 6Department of Physics, University of California, Davis, CA 95616, USA 7Department of Astronomy and Theoretical Astrophysics Center, University of California Berkeley, Berkeley, CA 94720 8Department of Physics, Whitworth University, 300 West Hawthorne Road, Spokane, Washington 99251, USA 9Department of Physics and Astronomy and CIERA, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA Working Draft ABSTRACT We analyze the cold dark matter density profiles of 54 galaxy halos simulated with FIRE-2 galaxy formation physics, each resolved within 0:5% of the halo virial radius. These halos contain galaxies with masses that range 4:5 11 from ultra-faint dwarfs (M? ' 10 M ) to the largest spirals (M? ' 10 M ) and have density profiles that are both cored and cuspy.
    [Show full text]
  • Gravitational Lensing of the Supernovae from the Supernova Legacy Survey (SNLS) Ayan Mitra
    Gravitational Lensing of the supernovae from the Supernova Legacy Survey (SNLS) Ayan Mitra To cite this version: Ayan Mitra. Gravitational Lensing of the supernovae from the Supernova Legacy Survey (SNLS). Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]. Sorbonne Universités, UPMC Univ Paris 06, CNRS, LIP6 UMR 7606, 4 place Jussieu 75005 Paris., 2016. English. tel-01797973 HAL Id: tel-01797973 https://tel.archives-ouvertes.fr/tel-01797973 Submitted on 23 May 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. THÈSE DE DOCTORAT DE L’UNIVERSITÉ PIERRE ET MARIE CURIE Spécialité Astrophysique et Cosmologie Particules, Noyaux et Cosmos (ED 517) Présentée par M. Ayan MITRA En vue de l’obtention du grade de DOCTEUR de l’UNIVERSITÉ PIERRE et MARIE CURIE Gravitational lensing of the supernovae from the SuperNova Legacy Survey Date de la soutenance : le 30 septembre 2016 devant le jury composé de : M. Dominique FOUCHEZ Examinateur Mme Delphine HARDIN Directrice de thèse M. Michael JOYCE Examinateur Mme Simona MEI Rapporteur Mme Cécile RENAULT Rapporteur Mme Vanina RUHLMANN-KLEIDER Examinateur ii Contents 1 Cosmology 3 1.1 A homogeneous expanding universe . .3 1.2 The Friedman universe .
    [Show full text]
  • Estimating Masses of Galaxy Clusters a first Step in Exploring Dark Matter
    Estimating masses of galaxy clusters a first step in exploring dark matter Master of Science Thesis in the Fundamental Physics program Elisabet Liljeblad Department of Earth and Space Sciences Chalmers University of Technology Gothenburg, Sweden, 2012 Primary supervisor: Kristian Pedersen Consultants and collaborators: Radek Wojtak and Andreas Skielboe University of Copenhagen Niels Bohr Institute,Dark Cosmology Center Examiner: Magnus Thomasson Chalmers University of Technology Contents Estimating the mass of galaxy clusters Contents 1 Introduction 1 1.1 Background . .1 1.2 Method and goals . .2 2 Theory and Methods 3 2.1 Virial Theorem . .3 2.2 Mass Estimators . .3 2.2.1 Virial Mass . .3 2.2.2 The Projected Mass . .4 2.3 Mass function by Klypin et al. .4 2.4 Galaxy velocities with respect to cluster center . .5 2.5 Spherical Law of Cosines and Distance Between Galaxies and Clusters . .6 2.6 Overdensity . .6 2.7 MATLAB . .6 2.8 Bootstrapping . .7 2.9 Estimating the cluster mass function . .7 2.10 Data . .8 2.10.1 SDSS . .8 2.10.2 GMBCG . .8 2.10.3 200 clusters from Wang et al. (2012) . .9 3 Analysis 11 3.1 Procedure . 11 3.2 Interloper Removal Methods . 13 3.2.1 The Initial Velocity Constraints and Distance Constraints . 13 3.2.2 The Maximum Velocity Approach . 13 3.2.3 The 2-3σ-clipping Approach . 15 3.2.4 The Maximum Velocity Gap Approach . 15 3.2.5 The Virial Mass Projected Mass Ratio Approach . 16 4 Results 17 4.1 Mass function . 17 4.2 The Maximum Velocity Approach .
    [Show full text]
  • Cosmological Constraints from the Virial Mass Function of Nearby
    Cosmological Constraints from the Virial Mass Function of Nearby Galaxy Groups and Clusters by James Colin Hill Submitted to the Department of Physics in partial fulfillment of the requirements for the degree of Bachelor of Science at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY June 2008 @ James Colin Hill, MMVIII. All rights reserved. The author hereby grants to MIT permission to reproduce and distribute publicly paper and electronic copies of this thesis document in whole or in part. Author. Department of Physics May 16, 2008 Certified by. (I Professor Claude R. Canizares Department of Physics Thesis Supervisor Certified by.. Dr. Kenneth J. Rines Harvard-Smithsonian Center for Astrophysics Thesis Supervisor Accepted by ........ Professor David E. Pritchard MASSACHUSETTS INSTiTUTE OF TECHNOLOGY Senior Thesis Coordinator, Department of Physics JUN 132008 LIBRARIES Cosmological Constraints from the Virial Mass Function of Nearby Galaxy Groups and Clusters by James Colin Hill Submitted to the Department of Physics on May 16, 2008, in partial fulfillment of the requirements for the degree of Bachelor of Science Abstract In this thesis, I present a new determination of the cluster mass function in a volume 107 h -3 Mpc3 using the ROSAT-2MASS-FAST Group Survey (R2FGS). R2FGS is an X-ray-selected sample of systems from the ROSAT All-Sky Survey in the region 6 > 0' and 0.01 < z < 0.06, with target galaxies for each system compiled from the Two Micron All Sky Survey (2MASS). The sample is designed to focus on low- mass groups and clusters, so as to break a degeneracy between the cosmological parameters m, and os.
    [Show full text]
  • Virial Masses and the Baryon Fraction in Galaxies1 H
    The Astrophysical Journal, 635:73–85, 2005 December 10 A # 2005. The American Astronomical Society. All rights reserved. Printed in U.S.A. VIRIAL MASSES AND THE BARYON FRACTION IN GALAXIES1 H. Hoekstra,2,3,4 B. C. Hsieh,5,6 H. K. C. Yee,4 H. Lin,7 and M. D. Gladders8 Received 2005 April 28; accepted 2005 July 30 ABSTRACT We have measured the weak-lensing signal as a function of rest-frame B-, V-, and R-band luminosity for a sample of ‘‘isolated’’ galaxies. These results are based on four-band photometry from the Red-Sequence Cluster Survey, enabling us to determine photometric redshifts for a large number of galaxies. We select a secure sample of lenses with photometric redshifts 0:2 < z < 0:4 and study the relation between the virial mass and baryonic contents. In addition, we discuss the implications of the derived photometric redshift distribution for published cosmic shear studies. The virial masses are derived from a fit to the observed lensing signal. For a galaxy with a fiducial lumi- 10 À2 þ1:5 ; 11 nosity of 10 h LB, , we obtain a mass Mvir ¼ 9:9À1:3 10 M . The virial mass as a function of luminosity is consistent with a power law /L1.5, with similar slopes for the three filters considered here. These findings are in excellent agreement with results from the Sloan Digital Sky Survey and semianalytic models of galaxy formation. We measure the fraction of mass in stars and the baryon fraction in galaxies by comparing the virial mass-to-light ratio to predicted stellar mass-to-light ratios.
    [Show full text]