The Historical 1900 and 1913 Outbursts of the Binary Blazar Candidate OJ287
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Very High Energy Emission from Blazars Interpreted Through Simultaneous Multiwavelength Observations
UNIVERSITA` DEGLI STUDI DI SIENA FACOLTA` DI SCIENZE MATEMATICHE, FISICHE E NATURALI Dipartimento di Fisica Very High Energy emission from blazars interpreted through simultaneous multiwavelength observations Relatore/Supervisor: Candidato/Candidate: Dr. Antonio Stamerra Giacomo Bonnoli Tutore/Tutor: Prof. Riccardo Paoletti Ph.D. School in Physics Cycle XXI December 2010 Abstract In the framework of Astroparticle Physics the understanding of the particle acceleration process and related high energy electromagnetic emission within astrophysical sources is an issue of fundamental importance to unravel the structure and evolution of many classes of celestial objects, on different scales from micro{quasars to active galactic nuclei. This has an important role not only for astrophysics itself, but for many related topics of cosmic ray physics and High Energy physics, such as the search for dark matter. Also cosmology is interested, as deepening our knowledge on Active Galactic Nuclei and their interaction with the environment can help to clarify open issues on the formation of cosmic structures and evolution of universe on large scales. The present view on sources emitting high energy radiation is now gaining new insight thanks to multiwavelength observations. This approach allows to explore the spectral energy distribution of the sources all across the electromagnetic spectrum, therefore granting the best achievable understanding of the physical processes that originate the radiation that we see, and their mutual relationships. Our theories model the sources in terms of parameters that can be inferred from the observables quantities measured, and the multiwavelength observations are a key instrument in order to rule out or support some selected models out of the many that compete in the effort of describing the processes at work. -
Dynamics and Evolution of Supermassive Black Holes in Merging Galaxies
Dynamics and Evolution of Supermassive Black Holes in Merging Galaxies Fazeel Mahmood Khan Astronomisches Rechen-Institut Zentrum f¨urAstronomie der Universit¨atHeidelberg Heidelberg 2011 Cover picture: Gemini image of NGC 5426-27 (Arp 271). Dissertation submitted to the Combined Faculties for the Natural Sciences and for Mathematics of the Ruperto-Carola University of Heidelberg, Germany for the degree of Doctor of Natural Sciences Put forward by Fazeel Mahmood Khan Born in: Azad Kashmir, Pakistan Oral examination: January 25, 2012 Dynamics and Evolution of Supermassive Black Holes in Merging Galaxies Referees: PD Dr. Andreas Just Prof. Dr. Volker Springel Abstract Supermassive black holes (SMBHs) are ubiquitous in galaxy centers and are correlated with their hosts in fundamental ways, suggesting an intimate link between SMBH and galaxy evolution. In the paradigm of hierarchical galaxy formation this correlation demands prompt coalescence of SMBH binaries, presumably due to dynamical friction, interaction of stars and gas with the binary and finally due to gravitational wave emission. If they are able to coalesce in less than a Hubble time, SMBH binaries will be a promising source of gravitational waves for gravitational wave detectors. However, it has been suggested that SMBH binaries may stall at a separation of 1 parsec. This stalling is sometimes referred to as the \Final Parsec Problem (FPP)". This study uses N-body simulations to test an improved formula for the orbital decay of SMBHs due to dynamical friction. Using a large set of N-body simulations, we show that the FPP does not occur in galaxies formed via mergers. The non spherical shape of the merger remnants ensures a constant supply of stars for the binary to interact with. -
Life and Adventures of Binary Supermassive Black Holes
Life and adventures of binary supermassive black holes Eugene Vasiliev Lebedev Physical Institute Plan of the talk • Why binary black holes? • Evolutionary stages: – galaxy merger and dynamical friction: the first contact – king of the hill: the binary hardens – the lean years: the final parsec problem – runaway speedup: gravitational waves kick in – anschluss • Life after merger • Perspectives of detection Origin of binary supermassive black holes • Most galaxies are believed to host central massive black holes • In the hierarchical merger paradigm, galaxies in the Universe have typically 1-3 major and multiple minor mergers in their lifetime • Every such merger brings two central black holes from parent galaxies together to form a binary system • We don’t see much evidence for widespread binary SMBH (to say the least) – therefore they need to merge rather efficiently • Merger is a natural way of producing huge black holes from smaller seeds Evolutionary track of binary SMBH • Merger of two galaxies creates a common nucleus; dynamical friction rapidly brings two black holes together to form a binary (a~10 pc) • Three-body interaction of binary with stars of galactic nucleus ejects most stars from the vicinity of the binary by the slingshot effect; a “mass deficit” is created and the binary becomes “hard” (a~1 pc) • The binary further shrinks by scattering off stars that continue to flow into the “loss cone”, due to two-body relaxation or other factors • As the separation reaches ~10–2 pc, gravitational wave emission becomes the dominant mechanism that carries away the energy • Reaching a few Schwarzschild radii (~10–5 pc), the binary finally merges Evolution timescales I. -
Binary Black Holes: an Introduction
Binary Black Holes: An Introduction Roger Blandford KIPAC Stanford 29 xi 2012 Tucson 1 Inertial Confinement of Extended Radio Sources Three‐Dimensional Magnetohydrodynamic Simulations of Buoyant Bubbles in Galaxy Clusters De Young and Axford 1967, Nature O’Neill, De Young and Jones 2011 29 xi 2012 Tucson 2 Mergers and Acquisitions • Mpc Problem • kpc Problem • pc Problem • mpc Problem 29 xi 2012 Tucson 3 The Megaparsec Problem • Galaxies with Spheroids have massive black holes (MBH) 4 -3 – m8~σ200 ; m ~ 10 Msph – Evolution? (Treu et al) • Galaxies assembled through hierarchical mergers of DM halos. – Major and minor – Halo Occupation Density Mayer – DM simulations quantitative; gas messy 29 xi 2012 Tucson 4 Can we calculate R(m1,m2,z,ρ…)? Energy self-sufficiency? • Kocevski eg (2012) [CANDELS] – Modest power – X-ray selected – Imaged in NIR – z~2 • AGN – ~0.5 in disks; ~0.3 in spheroids – >0.8 undisturbed like control sample • Selection effects rampant! – Opposite conclusions drawn from other studies 29 xi 2012 Tucson 5 How do we ask the right questions observationally? The kiloparsec Problem • Circum-Nuclear Disks – ULIRGs ~ 100pc – Sgr A* ~ 1 pc • Invoked to supply friction – Is it necessary for merger? 29 xi 2012 Tucson 6 Max et al Double AGN • Sample – SDSSIII etc – Double-peaked spectra • O[III] 5007 ΔV ~ 300-1000 km s-1 Blecha – Adaptive optics – X-rays, radio – Spectra • Are they outflows/jets/NLR? Double gas, disks, holes, NLR? 29 xi 2012 Tucson 7 Deadbeat Dads? • Are quasars mergers of two gas-rich galaxies • Is there a deficit -
Supermassive Black-Hole Demographics & Environments
Astro2020 Science White Paper Supermassive Black-hole Demographics & Environments With Pulsar Timing Arrays Principal authors Stephen R. Taylor (California Institute of Technology), [email protected] Sarah Burke-Spolaor (West Virginia University/Center for Gravitational Waves and Cosmology/CIFAR Azrieli Global Scholar), [email protected] Co-authors • Paul T. Baker (West Virginia University) • Maria Charisi (California Institute of Technology) • Kristina Islo (University of Wisconsin-Milwaukee) • Luke Z. Kelley (Northwestern University) • Dustin R. Madison (West Virginia University) • Joseph Simon (Jet Propulsion Laboratory, California Institute of Technology) • Sarah Vigeland (University of Wisconsin-Milwaukee) This is one of five core white papers written by members of the NANOGrav Collaboration. Related white papers • Nanohertz Gravitational Waves, Extreme Astrophysics, And Fundamental Physics With arXiv:1903.08183v1 [astro-ph.GA] 19 Mar 2019 Pulsar Timing Arrays, J. Cordes, M. McLaughlin, et al. • Fundamental Physics With Radio Millisecond Pulsars, E. Fonseca, et al. • Physics Beyond The Standard Model With Pulsar Timing Arrays, X. Siemens, et al. • Multi-messenger Astrophysics With Pulsar-timing Arrays, L. Z. Kelley, et al. Thematic Areas: Planetary Systems Star and Planet Formation Formation and Evolution of Compact Objects X Cosmology and Fundamental Physics Stars and Stellar Evolution Resolved Stellar Populations and their Environments X Galaxy Evolution X Multi-Messenger Astronomy and Astrophysics 1 Science Opportunity: Probing the Supermassive Black Hole Population With Gravitational Waves 6 9 With masses in the range 10 {10 M , supermassive black holes (SMBHs) are the most massive compact objects in the Universe. They lurk in massive galaxy centers, accreting inflowing gas, and powering jets that regulate their further accretion as well as galactic star formation. -
Gravitational Waves from Binary Supermassive Black Holes Missing in Pulsar Observations Authors: R
Gravitational waves from binary supermassive black holes missing in pulsar observations Authors: R. M. Shannon1,2*, V. Ravi3*, L. T. Lentati4, P. D. Lasky5, G. Hobbs1, M. Kerr1, R. N. Manchester1, W. A. Coles6, Y. Levin5, M. Bailes3, N. D. R. Bhat2, S. Burke-Spolaor7, S. Dai1,8, M. J. Keith9, S. Osłowski10,11, D. J. Reardon5, W. van Straten3, L. Toomey1, J.-B. Wang12, L. Wen13, J. S. B. Wyithe14, X.-J. Zhu13 Affiliations: 1 CSIRO Astronomy and Space Science, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia. 2 International Centre for Radio Astronomy Research, Curtin University, Bentley, WA 6102, Australia. 3 Centre for Astrophysics and Supercomputing, Swinburne University of Technology, PO Box 218, Hawthorn, VIC 3122, Australia. 4 Astrophysics Group, Cavendish Laboratory, JJ Thomson Avenue, Cambridge CB3 0HE, UK. 5 Monash Centre for Astrophysics, School of Physics and Astronomy, Monash University, PO Box 27, VIC 3800, Australia. 6 Department of Electrical and Computer Engineering, University of California at San Diego, La Jolla, CA 92093, USA. 7 National Radio Astronomical Observatory, Array Operations Center, P.O. Box O, Socorro, NM 87801-0387, USA. 8 Department of Astronomy, School of Physics, Peking University, Beijing, 100871, China. 9 Jodrell Bank Centre for Astrophysics, University of Manchester, M13 9PL, UK. 10 Department of Physics, Universitat Bielefeld, Universitatsstr 25, D-33615 Bielefeld, Germany. 11 Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany. 12 Xinjiang Astronomical Observatory, CAS, 150 Science 1-Street, Urumqi, Xinjiang 830011, China. 13 School of Physics, University of Western Australia, Crawley, WA 6009, Australia. -
Trumpet Initial Data for Highly Boosted Black Holes and High Energy Binaries
TRUMPET INITIAL DATA FOR HIGHLY BOOSTED BLACK HOLES AND HIGH ENERGY BINARIES Kyle Patrick Slinker A dissertation submitted to the faculty at the University of North Carolina at Chapel Hill in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Physics and Astronomy. Chapel Hill 2017 Approved by: Charles R. Evans J. Christopher Clemens Louise A. Dolan Joaqu´ınE. Drut Fabian Heitsch Reyco Henning c 2017 Kyle Patrick Slinker ALL RIGHTS RESERVED ii ABSTRACT Kyle Patrick Slinker: Trumpet Initial Data for Highly Boosted Black Holes and High Energy Binaries (Under the direction of Charles R. Evans) Initial data for a single boosted black hole is constructed that analytically contains no initial transient (junk) gravitational radiation and is adapted to the moving punctures gauge conditions. The properties of this data are investigated in detail. It is found to be generally superior to canonical Bowen-York data and, when implemented numerically in simulations, yields orders of magnitude less junk gravitational radiation content and more accurate black hole velocities. This allows for modeling of black holes that are boosted faster than previously possible. An approximate superposition of the data is used to demonstrate how a binary black hole system can be constructed to retain the advantages found for the single black hole. Extensions to black holes with spin are considered. iii TABLE OF CONTENTS LIST OF TABLES ............................................. vii LIST OF FIGURES ............................................ viii LIST OF ABBREVIATIONS AND SYMBOLS ........................... xii 1 Introduction ............................................... 1 1.1 Testing General Relativity Through Gravitational Wave Astronomy . 1 1.2 Numerical Relativity . 2 1.3 Project Goals . -
IAU Symp 269, POST MEETING REPORTS
IAU Symp 269, POST MEETING REPORTS C.Barbieri, University of Padua, Italy Content (i) a copy of the final scientific program, listing invited review speakers and session chairs; (ii) a list of participants, including their distribution on gender (iii) a list of recipients of IAU grants, stating amount, country, and gender; (iv) receipts signed by the recipients of IAU Grants (done); (v) a report to the IAU EC summarizing the scientific highlights of the meeting (1-2 pages). (vi) a form for "Women in Astronomy" statistics. (i) Final program Conference: Galileo's Medicean Moons: their Impact on 400 years of Discovery (IAU Symposium 269) Padova, Jan 6-9, 201 Program Wednesday 6, location: Centro San Gaetano, via Altinate 16.0 0 – 18.00 meeting of Scientific Committee (last details on the Symp 269; information on the IYA closing ceremony program) 18.00 – 20.00 welcome reception Thursday 7, morning: Aula Magna University 8:30 – late registrations 09.00 – 09.30 Welcome Addresses (Rector of University, President of COSPAR, Representative of ESA, President of IAU, Mayor of Padova, Barbieri) Session 1, The discovery of the Medicean Moons, the history, the influence on human sciences Chair: R. Williams Speaker Title 09.30 – 09.55 (1) G. Coyne Galileo's telescopic observations: the marvel and meaning of discovery 09.55 – 10.20 (2) D. Sobel Popular Perceptions of Galileo 10.20 – 10.45 (3) T. Owen The slow growth of human humility (read by Scott Bolton) 10.45 – 11.10 (4) G. Peruzzi A new Physics to support the Copernican system. Gleanings from Galileo's works 11.10 – 11.35 Coffee break Session 1b Chair: T. -
Pos(AASKA14)151
Multiple supermassive black hole systems: SKA’s future leading role PoS(AASKA14)151 Roger Deane∗1;2, Zsolt Paragi3, Matt Jarvis4;5, Mickäel Coriat1;2, Gianni Bernardi2;6;7, Sandor Frey8, Ian Heywood9;6, Hans-Rainer Klöckner10 1 University of Cape Town, 2 Square Kilometre Array South Africa, 3 Joint Institute for VLBI in Europe, 4 University of Oxford, 5 University of the Western Cape, 6 Rhodes University, 7 Harvard-Smithsonian Center for Astrophysics, 8 FÖMI Satellite Geodetic Observatory, 9 CSIRO Astronomy and Space Science, 10 Max-Planck-Institut für Radioastronomie E-mail: roger.deane [at] ast.uct.ac.za Galaxies and supermassive black holes (SMBHs) are believed to evolve through a process of hierarchical merging and accretion. Through this paradigm, multiple SMBH systems are expected to be relatively common in the Universe. However, to date there are poor observational constraints on multiple SMBHs systems with separations comparable to a SMBH gravitational sphere of influence (« 1 kpc). In this chapter, we discuss how deep continuum observations with the SKA will make leading contributions towards understanding how multiple black hole systems impact galaxy evolution. In addition, these observations will provide constraints on and an understanding of stochastic gravitational wave background detections in the pulsar timing array sensitivity band (nHz -mHz). We also discuss how targets for pointed gravitational wave experiments (that cannot be resolved by VLBI) could potentially be found using the large-scale radio-jet morphology, which can be modulated by the presence of a close-pair binary SMBH system. The combination of direct imaging at high angular resolution; low-surface brightness radio-jet tracers; and pulsar timing arrays will allow the SKA to trace black hole binary evolution from separations of a galaxy virial radius down to the sub-parsec level. -
A RADIO RELIC and a SEARCH for the CENTRAL BLACK HOLE in the ABELL 2261 BRIGHTEST CLUSTER GALAXY Sarah Burke-Spolaor1,2,3,4 Kayhan Gultekin¨ 5, Marc Postman6, Tod R
Faculty Scholarship 2017 A Radio Relic And A Search For The eC ntral Black Hole In The Abell 2261 Brightest Cluster Galaxy Sarah Burke-Spolaor Kayhan Gültekin Marc Postman Tod R. Lauer Joanna M. Taylor See next page for additional authors Follow this and additional works at: https://researchrepository.wvu.edu/faculty_publications Digital Commons Citation Burke-Spolaor, Sarah; Gültekin, Kayhan; Postman, Marc; Lauer, Tod R.; Taylor, Joanna M.; Lazio, T. Joseph W.; and Moustakas, Leonidas A., "A Radio Relic And A Search For The eC ntral Black Hole In The Abell 2261 Brightest Cluster Galaxy" (2017). Faculty Scholarship. 448. https://researchrepository.wvu.edu/faculty_publications/448 This Article is brought to you for free and open access by The Research Repository @ WVU. It has been accepted for inclusion in Faculty Scholarship by an authorized administrator of The Research Repository @ WVU. For more information, please contact [email protected]. Authors Sarah Burke-Spolaor, Kayhan Gültekin, Marc Postman, Tod R. Lauer, Joanna M. Taylor, T. Joseph W. Lazio, and Leonidas A. Moustakas This article is available at The Research Repository @ WVU: https://researchrepository.wvu.edu/faculty_publications/448 Draft version September 5, 2018 Preprint typeset using LATEX style emulateapj v. 12/16/11 A RADIO RELIC AND A SEARCH FOR THE CENTRAL BLACK HOLE IN THE ABELL 2261 BRIGHTEST CLUSTER GALAXY Sarah Burke-Spolaor1,2,3,4 Kayhan Gultekin¨ 5, Marc Postman6, Tod R. Lauer7, Joanna M. Taylor6, T. Joseph W. Lazio8, and Leonidas A. Moustakas8 Draft version September 5, 2018 ABSTRACT We present VLA images and HST/STIS spectra of sources within the center of the brightest cluster galaxy (BCG) in Abell 2261. -
Gamma Ray Bursts from Binary Black Holes
Gamma ray bursts from binary black holes Agnieszka Janiuk Center for Theoretical Physics, Polish Academy of Sciences, Warsaw Collaboration: Szymon Charzyński (Warsaw University) Michał Bejger (Copernicus Astronomical Center, Warsaw) www.cft.edu.pl A&A, 2013, 560, 25 Gamma Ray Bursts Prompt emission in Gamma, late-time emission with X-rays Energetic explosions connected with collapse of massive stars or compact object mergers Especially interesting is scenario when two compact objects merge within a collapsar Electromagnetic signal accompanied by gravitational waves We unify the two “standard” models Massive star explosion and mass fallback from the envelope Paczyński (1998); McFadyen & Compact binary merger: neutron Woosley (1999) star disruption Eichler et al. (1989); Ruffert & Janka (1999) Compact companion enters the massive star's envelope Common envelope phase, transient phase (analog of a Thorne-Żytkov object) Trigger of the core collapse, SN (Hypernova) explosion -> GRB Ultimate fate of HMXBs: Binary pulsar NS-BH BH-BH Possible progenitors: known high mass X-ray binaries Close binary: massive OB star plus compact remnant Examples: Cyg X-3, IC 10 X-1, NGC 300 X-1, M33 X-7 Statistics: the advanced LIGO/VIRGO detection rate of BH-BH mergers from Cyg X-3 formation channel is estimated at 10 yr-1 BH HMXBs formed at z>6 might have impact on cosmic reionisation. Their Zhang & Fryer (2001); Barkov & fraction should increase with redshift Komissarov (2010); Church et al. (2012); Belczyński et al. (2013); Mirabel et al (2011) Our scenario -
Pete and Paul's Observing Challenges
BAA Winchester Weekend 2019 Pete and Paul’s Observing Challenges Pete Lawrence & Paul G. Abel. Challenge 1: Observing the Transit of Mercury On 2019 November 11th the planet Mercury will pass in front of the sun. The first challenge is to observe the transit. The chart below gives the start and end time of the transit along with Mercury’s path across the sun. If you have a refractor under 150mm aperture you can project the Sun and observe the transit in white light. Alternatively certified solar film can be used to make any telescope safe for solar viewing by covering the entire front aperture – remember to cap or remove the finder! Another method is to observe with a hydrogen-alpha telescope directly. BE CAREFUL WHEN OBSERVING THE SUN! Never observe the Sun directly without a certified filter. UK observers will be able to observe the start of the transit but the Sun will set before the transit concludes. 1 Challenge 2: Viewing Mercury Against the Spicule Layer at the Start of the Transit Just before the start of the transit, Mercury will pass against the spicule layer of the Sun. The spicule layer is a cross-section through the chromosphere as seen at the edge of the Sun via a hydrogen alpha filter. It is not visible in white light, only H-alpha, so you will need a solar telescope for this challenge. In H-alpha, Mercury will appear as a black silhouette against the spicule layer (see image below). It’s best to start observing from around 1215UT- make sure you know which side is east and west in your telescope! If you get the wrong side, you will miss the event and remember the sun sets from the UK by the time the transit ends.