Diffuse Radio Emission from Galaxy Clusters
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Arxiv:1903.02002V1 [Astro-Ph.GA] 5 Mar 2019
Draft version March 7, 2019 Typeset using LATEX twocolumn style in AASTeX62 RELICS: Reionization Lensing Cluster Survey Dan Coe,1 Brett Salmon,1 Maruˇsa Bradacˇ,2 Larry D. Bradley,1 Keren Sharon,3 Adi Zitrin,4 Ana Acebron,4 Catherine Cerny,5 Nathalia´ Cibirka,4 Victoria Strait,2 Rachel Paterno-Mahler,3 Guillaume Mahler,3 Roberto J. Avila,1 Sara Ogaz,1 Kuang-Han Huang,2 Debora Pelliccia,2, 6 Daniel P. Stark,7 Ramesh Mainali,7 Pascal A. Oesch,8 Michele Trenti,9, 10 Daniela Carrasco,9 William A. Dawson,11 Steven A. Rodney,12 Louis-Gregory Strolger,1 Adam G. Riess,1 Christine Jones,13 Brenda L. Frye,7 Nicole G. Czakon,14 Keiichi Umetsu,14 Benedetta Vulcani,15 Or Graur,13, 16, 17 Saurabh W. Jha,18 Melissa L. Graham,19 Alberto Molino,20, 21 Mario Nonino,22 Jens Hjorth,23 Jonatan Selsing,24, 25 Lise Christensen,23 Shotaro Kikuchihara,26, 27 Masami Ouchi,26, 28 Masamune Oguri,29, 30, 28 Brian Welch,31 Brian C. Lemaux,2 Felipe Andrade-Santos,13 Austin T. Hoag,2 Traci L. Johnson,32 Avery Peterson,32 Matthew Past,32 Carter Fox,3 Irene Agulli,4 Rachael Livermore,9, 10 Russell E. Ryan,1 Daniel Lam,33 Irene Sendra-Server,34 Sune Toft,24, 25 Lorenzo Lovisari,13 and Yuanyuan Su13 1Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA 2Department of Physics, University of California, Davis, CA 95616, USA 3Department of Astronomy, University of Michigan, 1085 South University Ave, Ann Arbor, MI 48109, USA 4Physics Department, Ben-Gurion University of the Negev, P.O. -
The Puzzle of the Strange Galaxy Made of 99.9% Dark Matter Is Solved 13 October 2020
The puzzle of the strange galaxy made of 99.9% dark matter is solved 13 October 2020 The galaxy Dragonfly 44 was discovered in a deep survey of the Coma cluster, a cluster with several thousand galaxies. From the start, the galaxy was considered remarkable by the researchers because the quantity of dark matter they inferred was almost as much as that in the Milky Way, the equivalent of a billion solar masses. However, instead of containing around a hundred thousand million stars, as has the Milky Way, DF44 has only a hundred million stars, a thousand times Image and amplification (in color) of the ultra-diffuse fewer. This means that the amount of dark matter galaxy Dragonfly 44 taken with the Hubble space was ten thousand times greater than that of its telescope. Credit: Teymoor Saifollahi and NASA/HST. stars. If this had been true, it would have been a unique object, with almost 100 times as much dark matter as that expected from the number of its stars. At present, the formation of galaxies is difficult to understand without the presence of a ubiquitous, Nevertheless, by an exhaustive analysis of the but mysterious component, termed dark matter. system of globular cluster around Dragonfly 44, the Astronomers have measure how much dark matter researchers have detected that the total number of there is around galaxies, and have found that it globular clusters is only 20, and that the total varies between 10 and 300 times the quantity of quantity of dark matter is around 300 times that of visible matter. -
PUBLICATIONS Publications (As of Dec 2020): 335 on Refereed Journals, 90 Selected from Non-Refereed Journals. Citations From
PUBLICATIONS Publications (as of Sep 2021): 350 on refereed journals, 92 selected from non-refereed journals. Citations from ADS: 32263, H-index= 97. Refereed 350. Caminha, G.B.; Suyu, S.H.; Grillo, C.; Rosati, P.; et al. 2021 Galaxy cluster strong lensing cosmography: cosmological constraints from a sample of regular galaxy clusters, submitted to A&A 349. Mercurio, A..; Rosati, P., Biviano, A. et al. 2021 CLASH-VLT: Abell S1063. Cluster assembly history and spectroscopic catalogue, submitted to A&A, (arXiv:2109.03305) 348. G. Granata et al. (9 coauthors including P. Rosati) 2021 Improved strong lensing modelling of galaxy clusters using the Fundamental Plane: the case of Abell S1063, submitted to A&A, (arXiv:2107.09079) 347. E. Vanzella et al. (19 coauthors including P. Rosati) 2021 High star cluster formation efficiency in the strongly lensed Sunburst Lyman-continuum galaxy at z = 2:37, submitted to A&A, (arXiv:2106.10280) 346. M.G. Paillalef et al. (9 coauthors including P. Rosati) 2021 Ionized gas kinematics of cluster AGN at z ∼ 0:8 with KMOS, MNRAS, 506, 385 6 crediti 345. M. Scalco et al. (12 coauthors including P. Rosati) 2021 The HST large programme on Centauri - IV. Catalogue of two external fields, MNRAS, 505, 3549 344. P. Rosati et al. 2021 Synergies of THESEUS with the large facilities of the 2030s and guest observer opportunities, Experimental Astronomy, 2021ExA...tmp...79R (arXiv:2104.09535) 343. N.R. Tanvir et al. (33 coauthors including P. Rosati) 2021 Exploration of the high-redshift universe enabled by THESEUS, Experimental Astronomy, 2021ExA...tmp...97T (arXiv:2104.09532) 342. -
A High Stellar Velocity Dispersion and ~100 Globular Clusters for the Ultra
San Jose State University From the SelectedWorks of Aaron J. Romanowsky 2016 A High Stellar Velocity Dispersion and ~100 Globular Clusters for the Ultra-Diffuse Galaxy Dragonfly 44 Pieter van Dokkum, Yale University Roberto Abraham, University of Toronto Jean P. Brodie, University of California Observatories Charlie Conroy, Harvard-Smithsonian Center for Astrophysics Shany Danieli, Yale University, et al. Available at: https://works.bepress.com/aaron_romanowsky/117/ The Astrophysical Journal Letters, 828:L6 (6pp), 2016 September 1 doi:10.3847/2041-8205/828/1/L6 © 2016. The American Astronomical Society. All rights reserved. A HIGH STELLAR VELOCITY DISPERSION AND ∼100 GLOBULAR CLUSTERS FOR THE ULTRA-DIFFUSE GALAXY DRAGONFLY 44 Pieter van Dokkum1, Roberto Abraham2, Jean Brodie3, Charlie Conroy4, Shany Danieli1, Allison Merritt1, Lamiya Mowla1, Aaron Romanowsky3,5, and Jielai Zhang2 1 Astronomy Department, Yale University, New Haven, CT 06511, USA 2 Department of Astronomy & Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4, Canada 3 University of California Observatories, 1156 High Street, Santa Cruz, CA 95064, USA 4 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA, USA 5 Department of Physics and Astronomy, San José State University, San Jose, CA 95192, USA Received 2016 June 20; revised 2016 July 14; accepted 2016 July 15; published 2016 August 25 ABSTRACT Recently a population of large, very low surface brightness, spheroidal galaxies was identified in the Coma cluster. The apparent survival of these ultra-diffuse galaxies (UDGs) in a rich cluster suggests that they have very high masses. Here, we present the stellar kinematics of Dragonfly44, one of the largest Coma UDGs, using a 33.5 hr fi +8 -1 integration with DEIMOS on the Keck II telescope. -
THE DISTRIBUTION of ACTIVE GALACTIC NUCLEI in CLUSTERS of GALAXIES ABSTRACT We Present a Study of the Distribution of AGN In
APJ ACCEPTED [18 APRIL 2007] Preprint typeset using LATEX style emulateapj v. 12/14/05 THE DISTRIBUTION OF ACTIVE GALACTIC NUCLEI IN CLUSTERS OF GALAXIES PAUL MARTINI Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210, [email protected] JOHN S. MULCHAEY, DANIEL D. KELSON Carnegie Observatories, 813 Santa Barbara St., Pasadena, CA 91101-1292 ApJ accepted [18 April 2007] ABSTRACT We present a study of the distribution of AGN in clusters of galaxies with a uniformly selected, spectroscop- ically complete sample of 35 AGN in eight clusters of galaxies at z = 0:06 ! 0:31. We find that the 12 AGN 42 −1 with LX > 10 erg s in cluster members more luminous than a rest-frame MR < −20 mag are more centrally concentrated than typical cluster galaxies of this luminosity, although these AGN have comparable velocity and substructure distributions to other cluster members. In contrast, a larger sample of 30 cluster AGN with 41 −1 LX > 10 erg s do not show evidence for greater central concentration than inactive cluster members, nor evidence for a different kinematic or substructure distribution. As we do see clear differences in the spatial and kinematic distributions of the blue Butcher-Oemler and red cluster galaxy populations, any difference in the AGN and inactive galaxy population must be less distinct than that between these two pairs of popula- tions. Comparison of the AGN fraction selected via X-ray emission in this study to similarly-selected AGN in the field indicates that the AGN fraction is not significantly lower in clusters, contrary to AGN identified via visible-wavelength emission lines, but similar to the approximately constant radio-selected AGN fraction in clusters and the field. -
Radio Observations of the Merging Galaxy Cluster Abell 520 D
A&A 622, A20 (2019) Astronomy https://doi.org/10.1051/0004-6361/201833900 & c ESO 2019 Astrophysics LOFAR Surveys: a new window on the Universe Special issue Radio observations of the merging galaxy cluster Abell 520 D. N. Hoang1, T. W. Shimwell2,1, R. J. van Weeren1, G. Brunetti3, H. J. A. Röttgering1, F. Andrade-Santos4, A. Botteon3,5, M. Brüggen6, R. Cassano3, A. Drabent7, F. de Gasperin6, M. Hoeft7, H. T. Intema1, D. A. Rafferty6, A. Shweta8, and A. Stroe9 1 Leiden Observatory, Leiden University, PO Box 9513, NL-2300 RA Leiden, The Netherlands e-mail: [email protected] 2 Netherlands Institute for Radio Astronomy (ASTRON), PO Box 2, 7990 AA Dwingeloo, The Netherlands 3 INAF-Istituto di Radioastronomia, via P. Gobetti 101, 40129 Bologna, Italy 4 Harvard-Smithsonian for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 5 Dipartimento di Fisica e Astronomia, Università di Bologna, via P. Gobetti 93/2, 40129 Bologna, Italy 6 Hamburger Sternwarte, University of Hamburg, Gojenbergsweg 112, 21029 Hamburg, Germany 7 Thüringer Landessternwarte, Sternwarte 5, 07778 Tautenburg, Germany 8 Indian Institute of Science Education and Research (IISER), Pune, India 9 European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching, Germany Received 18 July 2018 / Accepted 10 September 2018 ABSTRACT Context. Extended synchrotron radio sources are often observed in merging galaxy clusters. Studies of the extended emission help us to understand the mechanisms in which the radio emitting particles gain their relativistic energies. Aims. We examine the possible acceleration mechanisms of the relativistic particles that are responsible for the extended radio emis- sion in the merging galaxy cluster Abell 520. -
Arxiv:1811.05004V2 [Astro-Ph.GA] 19 Dec 2018 2 the Atmospheric Cooling
Noname manuscript No. (will be inserted by the editor) Hot Atmospheres, Cold Gas, AGN Feedback and the Evolution of Early Type Galaxies: a Topical Perspective N. Werner · B. R. McNamara · E. Churazov · E. Scannapieco Received: date / Accepted: date Abstract Most galaxies comparable to or larger than the mass of the Milky Way host hot, X-ray emitting atmospheres, and many such galaxies are radio sources. Hot atmospheres and radio jets and lobes are the ingredients of radio- mechanical active galactic nucleus (AGN) feedback. While a consensus has emerged that such feedback suppresses cooling of hot cluster atmospheres, less attention has been paid to massive galaxies where similar mechanisms are at play. Observation indicates that the atmospheres of elliptical and S0 galaxies were accreted externally during the process of galaxy assembly and augmented significantly by stellar mass loss. Their atmospheres have entropy and cooling time profiles that are remarkably similar to those of central cluster galaxies. About half display filamentary or disky nebulae of cool and cold gas, much of which has likely cooled from the hot atmospheres. We review the observational and theoretical perspectives on thermal instabilities in galactic atmospheres and the evidence that AGN heating is able to roughly balance N. Werner MTA-E¨otv¨osUniversity Lend¨uletHot Universe and Astrophysics Research Group, P´azm´any P´eters´et´any 1/A, Budapest, 1117, Hungary Department of Theoretical Physics and Astrophysics, Faculty of Science, Masaryk Univer- sity, Kotl´aˇrsk´a2, Brno, 611 37, Czech Republic School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan E-mail: [email protected] B. -
INVESTIGATING ACTIVE GALACTIC NUCLEI with LOW FREQUENCY RADIO OBSERVATIONS By
INVESTIGATING ACTIVE GALACTIC NUCLEI WITH LOW FREQUENCY RADIO OBSERVATIONS by MATTHEW LAZELL A thesis submitted to The University of Birmingham for the degree of DOCTOR OF PHILOSOPHY School of Physics & Astronomy College of Engineering and Physical Sciences The University of Birmingham March 2015 University of Birmingham Research Archive e-theses repository This unpublished thesis/dissertation is copyright of the author and/or third parties. The intellectual property rights of the author or third parties in respect of this work are as defined by The Copyright Designs and Patents Act 1988 or as modified by any successor legislation. Any use made of information contained in this thesis/dissertation must be in accordance with that legislation and must be properly acknowledged. Further distribution or reproduction in any format is prohibited without the permission of the copyright holder. Abstract Low frequency radio astronomy allows us to look at some of the fainter and older synchrotron emission from the relativistic plasma associated with active galactic nuclei in galaxies and clusters. In this thesis, we use the Giant Metrewave Radio Telescope to explore the impact that active galactic nuclei have on their surroundings. We present deep, high quality, 150–610 MHz radio observations for a sample of fifteen predominantly cool-core galaxy clusters. We in- vestigate a selection of these in detail, uncovering interesting radio features and using our multi-frequency data to derive various radio properties. For well-known clusters such as MS0735, our low noise images enable us to see in improved detail the radio lobes working against the intracluster medium, whilst deriving the energies and timescales of this event. -
Small-Scale Structure Is It a Valid Motivation?
Small-scale Structure Is it a valid motivation? Jakub Scholtz IPPP (Durham) Small Scale Structure Problems <—> All the reasons why “CDM is not it” How did we get here? We are gravitationally sensitive to something sourcing T • <latexit sha1_base64="055AcnSYYRkGsBe2aYAe7vH1peg=">AAAB8XicbVDLSgNBEOz1GeMr6tHLYBA8hV0R9Bj04jFCXphdwuxkNhkyM7vMQwhL/sKLB0W8+jfe/BsnyR40saChqOqmuyvOONPG97+9tfWNza3t0k55d2//4LBydNzWqVWEtkjKU9WNsaacSdoyzHDazRTFIua0E4/vZn7niSrNUtk0k4xGAg8lSxjBxkmPzX4eChtKO+1Xqn7NnwOtkqAgVSjQ6Fe+wkFKrKDSEI617gV+ZqIcK8MIp9NyaDXNMBnjIe05KrGgOsrnF0/RuVMGKEmVK2nQXP09kWOh9UTErlNgM9LL3kz8z+tZk9xEOZOZNVSSxaLEcmRSNHsfDZiixPCJI5go5m5FZIQVJsaFVHYhBMsvr5L2ZS3wa8HDVbV+W8RRglM4gwsI4BrqcA8NaAEBCc/wCm+e9l68d+9j0brmFTMn8Afe5w/beZEG</latexit> µ⌫ —> we are fairly certain that DM exists. • An exception is MOND, which has issues of its own. However, the MOND community has been instrumental in pointing out some of the discrepancies with CDM. • But how do we verify the picture? —> NBODY simulations (disclaimer: I have never run a serious body simulation) 2WalterDehnen,JustinI.Read:N-body SimulationsN-body simulations of gravitational dynamics have reached over 106 particles [6], while collisionless calculations can now reach more than 109 particles [7–10]. This disparity reflects the difference in complexity of these rather dissimilar N-body problems. The significant increase in N in the last decade was driven by the usage of parallel computers. In this review, we discuss the state-of-the art software algo- Takerithms N and dark hardware matter improvements -
Chapter 1 the PHYSICS of CLUSTER MERGERS
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server To appear in Merging Processes in Clusters of Galaxies, edited by L. Feretti, I. M. Gioia, and G. Giovannini (Dordrecht: Kluwer), in press (2001) Chapter 1 THE PHYSICS OF CLUSTER MERGERS Craig L. Sarazin Department of Astronomy University of Virginia [email protected] Abstract Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. Some of the basic physical proper- ties of mergers will be discussed, with an emphasis on simple analytic arguments rather than numerical simulations. Semi-analytic estimates of merger rates are reviewed, and a simple treatment of the kinematics of binary mergers is given. Mergers drive shocks into the intracluster medium, and these shocks heat the gas and should also accelerate non- thermal relativistic particles. X-ray observations of shocks can be used to determine the geometry and kinematics of the merger. Many clus- ters contain cooling flow cores; the hydrodynamical interactions of these cores with the hotter, less dense gas during mergers are discussed. As a result of particle acceleration in shocks, clusters of galaxies should con- tain very large populations of relativistic electrons and ions. Electrons 2 with Lorentz factors γ 300 (energies E = γmec 150 MeV) are expected to be particularly∼ common. Observations and∼ models for the radio, extreme ultraviolet, hard X-ray, and gamma-ray emission from nonthermal particles accelerated in these mergers are described. -
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A&A 566, A68 (2014) Astronomy DOI: 10.1051/0004-6361/201322450 & c ESO 2014 Astrophysics Mass, velocity anisotropy, and pseudo phase-space density profiles of Abell 2142 E. Munari1,A.Biviano2,3, and G. A. Mamon3 1 Astronomy Unit, Department of Physics, University of Trieste, via Tiepolo 11, 34131 Trieste, Italy e-mail: [email protected] 2 INAF/Osservatorio Astronomico di Trieste, via Tiepolo 11, 34131 Trieste, Italy e-mail: [email protected] 3 Institut d’Astrophysique de Paris (UMR 7095: CNRS & UPMC), 98 bis Bd Arago, 75014 Paris, France e-mail: [email protected] Received 6 August 2013 / Accepted 12 April 2014 ABSTRACT Aims. We aim to compute the mass and velocity anisotropy profiles of Abell 2142 and, from there, the pseudo phase–space density profile Q(r) and the density slope − velocity anisotropy β − γ relation, and then to compare them with theoretical expectations. Methods. The mass profiles were obtained by using three techniques based on member galaxy kinematics, namely the caustic method, the method of dispersion-kurtosis, and MAMPOSSt. Through the inversion of the Jeans equation, it was possible to compute the velocity anisotropy profiles. Results. The mass profiles, as well as the virial values of mass and radius, computed with the different techniques agree with one another and with the estimates coming from X-ray and weak lensing studies. A combined mass profile is obtained by averaging the lensing, X-ray, and kinematics determinations. The cluster mass profile is well fitted by an NFW profile with c = 4.0 ± 0.5. The population of red and blue galaxies appear to have a different velocity anisotropy configuration, since red galaxies are almost isotropic, while blue galaxies are radially anisotropic, with a weak dependence on radius. -
Hst Frontier Fields Preliminary Map Modeling
HST FRONTIER FIELDS PRELIMINARY MAP MODELING CATs Team (Clusters As Telescopes) Johan Richard (CRAL Lyon), Benjamin Clement (University of Arizona), Mathilde Jauzac (University of KwaZulu-Natal), Eric Jullo (LAM Marseille), Marceau Limousin (LAM, Marseille), Harald Ebeling (IfA, Hawaii), Priyamvada Natarajan (Yale University), Jean-Paul Kneib (EPFL Lausanne) & Eiichi Egami (University of Arizona). RECONSTRUCTION METHODOLOGY Producing a magnification map involves solving the lens equation for light rays originating from distant sources and deflected by the massive foreground cluster. This is ultimately an inversion problem for which several sets of codes and approaches have been developed independently (see recent review by Kneib & Natarajan 2010). Our collaboration uses LENSTOOL1, an algorithm developed collectively by us over the years. LENSTOOL is a hybrid code that combines observational strong- and weak-lensing data to constrain the cluster mass model. The total mass distribution of clusters is assumed to consist of several smooth, large-scale potentials that are modeled either in a parametric form or non-parametrically, along with contributions from many (typically N > 50) individual cluster galaxies that are modeled using physically motivated parametric forms. For lensing clusters a multi-scale approach is optimal, in as much as the constraints resulting from this inversion exercise are derived from a range of scales. Further details of the methodology are outlined in Jullo & Kneib (2009) and have been extended to the weak-lensing regime (Jauzac et al. 2012). At present, the prevailing modeling approach is to assign a small-scale dark-matter clump to each major cluster galaxy and a large-scale dark-matter clump to prominent concentrations of cluster galaxies (Natarajan & Kneib 1997).