AGN Singularities and Jets Modelled with the Superstar Scenario
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Polarimetric Properties of Blazars Caught by the WEBT
galaxies Review Polarimetric Properties of Blazars Caught by the WEBT Claudia M. Raiteri * and Massimo Villata INAF, Osservatorio Astrofisico di Torino, via Osservatorio 20, I-10025 Pino Torinese, Italy; [email protected] * Correspondence: [email protected] Abstract: Active galactic nuclei come in many varieties. A minority of them are radio-loud, and exhibit two opposite prominent plasma jets extending from the proximity of the supermassive black hole up to megaparsec distances. When one of the relativistic jets is oriented closely to the line of sight, its emission is Doppler beamed and these objects show extreme variability properties at all wavelengths. These are called “blazars”. The unpredictable blazar variability, occurring on a continuous range of time-scales, from minutes to years, is most effectively investigated in a multi-wavelength context. Ground-based and space observations together contribute to give us a comprehensive picture of the blazar emission properties from the radio to the g-ray band. Moreover, in recent years, a lot of effort has been devoted to the observation and analysis of the blazar polarimetric radio and optical behaviour, showing strong variability of both the polarisation degree and angle. The Whole Earth Blazar Telescope (WEBT) Collaboration, involving many tens of astronomers all around the globe, has been monitoring several blazars since 1997. The results of the corresponding data analysis have contributed to the understanding of the blazar phenomenon, particularly stressing the viability of a geometrical interpretation of the blazar variability. We review here the most significant polarimetric results achieved in the WEBT studies. Keywords: active galactic nuclei; blazars; jets; polarimetry Citation: Raiteri, C.M.; Villata, M. -
Quantum Detection of Wormholes Carlos Sabín
www.nature.com/scientificreports OPEN Quantum detection of wormholes Carlos Sabín We show how to use quantum metrology to detect a wormhole. A coherent state of the electromagnetic field experiences a phase shift with a slight dependence on the throat radius of a possible distant wormhole. We show that this tiny correction is, in principle, detectable by homodyne measurements Received: 16 February 2017 after long propagation lengths for a wide range of throat radii and distances to the wormhole, even if the detection takes place very far away from the throat, where the spacetime is very close to a flat Accepted: 15 March 2017 geometry. We use realistic parameters from state-of-the-art long-baseline laser interferometry, both Published: xx xx xxxx Earth-based and space-borne. The scheme is, in principle, robust to optical losses and initial mixedness. We have not observed any wormhole in our Universe, although observational-based bounds on their abundance have been established1. The motivation of the search of these objects is twofold. On one hand, the theoretical implications of the existence of topological spacetime shortcuts would entail a challenge to our understanding of deep physical principles such as causality2–5. On the other hand, typical phenomena attributed to black holes can be mimicked by wormholes. Therefore, if wormholes exist the identity of the objects in the center of the galaxies might be questioned6 as well as the origin of the already observed gravitational waves7, 8. For these reasons, there is a renewed interest in the characterization of wormholes9–11 and in their detection by classical means such as gravitational lensing12, 13, among others14. -
Active Galactic Nuclei: a Brief Introduction
Active Galactic Nuclei: a brief introduction Manel Errando Washington University in St. Louis The discovery of quasars 3C 273: The first AGN z=0.158 2 <latexit sha1_base64="4D0JDPO4VKf1BWj0/SwyHGTHSAM=">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</latexit> <latexit sha1_base64="H7Rv+ZHksM7/70841dw/vasasCQ=">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</latexit> The power source of quasars • The luminosity (L) of quasars, i.e. how bright they are, can be as high as Lquasar ~ 1012 Lsun ~ 1040 W. • The energy source of quasars is accretion power: - Nuclear fusion: 2 11 1 ∆E =0.007 mc =6 10 W s g− -
Messier Objects
Messier Objects From the Stocker Astroscience Center at Florida International University Miami Florida The Messier Project Main contributors: • Daniel Puentes • Steven Revesz • Bobby Martinez Charles Messier • Gabriel Salazar • Riya Gandhi • Dr. James Webb – Director, Stocker Astroscience center • All images reduced and combined using MIRA image processing software. (Mirametrics) What are Messier Objects? • Messier objects are a list of astronomical sources compiled by Charles Messier, an 18th and early 19th century astronomer. He created a list of distracting objects to avoid while comet hunting. This list now contains over 110 objects, many of which are the most famous astronomical bodies known. The list contains planetary nebula, star clusters, and other galaxies. - Bobby Martinez The Telescope The telescope used to take these images is an Astronomical Consultants and Equipment (ACE) 24- inch (0.61-meter) Ritchey-Chretien reflecting telescope. It has a focal ratio of F6.2 and is supported on a structure independent of the building that houses it. It is equipped with a Finger Lakes 1kx1k CCD camera cooled to -30o C at the Cassegrain focus. It is equipped with dual filter wheels, the first containing UBVRI scientific filters and the second RGBL color filters. Messier 1 Found 6,500 light years away in the constellation of Taurus, the Crab Nebula (known as M1) is a supernova remnant. The original supernova that formed the crab nebula was observed by Chinese, Japanese and Arab astronomers in 1054 AD as an incredibly bright “Guest star” which was visible for over twenty-two months. The supernova that produced the Crab Nebula is thought to have been an evolved star roughly ten times more massive than the Sun. -
A Multimessenger View of Galaxies and Quasars from Now to Mid-Century M
A multimessenger view of galaxies and quasars from now to mid-century M. D’Onofrio 1;∗, P. Marziani 2;∗ 1 Department of Physics & Astronomy, University of Padova, Padova, Italia 2 National Institute for Astrophysics (INAF), Padua Astronomical Observatory, Italy Correspondence*: Mauro D’Onofrio [email protected] ABSTRACT In the next 30 years, a new generation of space and ground-based telescopes will permit to obtain multi-frequency observations of faint sources and, for the first time in human history, to achieve a deep, almost synoptical monitoring of the whole sky. Gravitational wave observatories will detect a Universe of unseen black holes in the merging process over a broad spectrum of mass. Computing facilities will permit new high-resolution simulations with a deeper physical analysis of the main phenomena occurring at different scales. Given these development lines, we first sketch a panorama of the main instrumental developments expected in the next thirty years, dealing not only with electromagnetic radiation, but also from a multi-messenger perspective that includes gravitational waves, neutrinos, and cosmic rays. We then present how the new instrumentation will make it possible to foster advances in our present understanding of galaxies and quasars. We focus on selected scientific themes that are hotly debated today, in some cases advancing conjectures on the solution of major problems that may become solved in the next 30 years. Keywords: galaxy evolution – quasars – cosmology – supermassive black holes – black hole physics 1 INTRODUCTION: TOWARD MULTIMESSENGER ASTRONOMY The development of astronomy in the second half of the XXth century followed two major lines of improvement: the increase in light gathering power (i.e., the ability to detect fainter objects), and the extension of the frequency domain in the electromagnetic spectrum beyond the traditional optical domain. -
A Supernova Origin for Dust in a High-Redshift Quasar
A SUPERNOVA ORIGIN FOR DUST IN A HIGH-REDSHIFT QUASAR R. Maiolino ∗, R. Schneider †∗, E. Oliva ‡∗, S. Bianchi §, A. Ferrara ¶, F. Mannucci§, M. Pedani‡, M. Roca Sogorb k ∗ INAF - Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy † “Enrico Fermi” Center, Via Panisperna 89/A, 00184 Roma, Italy ‡ Telescopio Nazionale Galileo, C. Alvarez de Abreu, 70, 38700 S.ta Cruz de La Palma, Spain § CNR-IRA, Sezione di Firenze, Largo Enrico Fermi 5, 50125 Firenze, Italy ¶ SISSA/International School for Advanced Studies, Via Beirut 4, 34100 Trieste, Italy k Astrofisico Fco. S`anchez, Universidad de La Laguna, 38206 La Laguna, Tenerife, Spain Interstellar dust plays a crucial role in the evolution of the Universe by assisting the formation of molecules1, by triggering the formation of the first low-mass stars2, and by absorbing stellar ultraviolet-optical light and subsequently re-emitting it at infrared/millimetre wavelengths. Dust is thought to be produced predominantly in the envelopes of evolved (age >1 Gyr), low-mass stars3. This picture has, however, recently been brought into question by the discovery of large masses of dust in the host galaxies of quasars4,5 at redshift z > 6, when the age of the Universe was less than 1 Gyr. Theoretical studies6,7,8, corroborated by observations of nearby supernova remnants9,10,11, have suggested that supernovae provide a fast and efficient dust formation environment in the early Universe. Here we report infrared observations of a quasar at redshift 6.2, which are used to obtain directly its dust extinction curve. We then show that such a curve is in excellent agreement with supernova dust models. -
New APS CEO: Jonathan Bagger APS Sends Letter to Biden Transition
Penrose’s Connecting students A year of Back Page: 02│ black hole proof 03│ and industry 04│ successful advocacy 08│ Bias in letters of recommendation January 2021 • Vol. 30, No. 1 aps.org/apsnews A PUBLICATION OF THE AMERICAN PHYSICAL SOCIETY GOVERNMENT AFFAIRS GOVERNANCE APS Sends Letter to Biden Transition Team Outlining New APS CEO: Jonathan Bagger Science Policy Priorities BY JONATHAN BAGGER BY TAWANDA W. JOHNSON Editor's note: In December, incoming APS CEO Jonathan Bagger met with PS has sent a letter to APS staff to introduce himself and President-elect Joe Biden’s answer questions. We asked him transition team, requesting A to prepare an edited version of his that he consider policy recom- introductory remarks for the entire mendations across six issue areas membership of APS. while calling for his administra- tion to “set a bold path to return the United States to its position t goes almost without saying of global leadership in science, that I am both excited and technology, and innovation.” I honored to be joining the Authored in December American Physical Society as its next CEO. I look forward to building by then-APS President Phil Jonathan Bagger Bucksbaum, the letter urges Biden matically improve the current state • Stimulus Support for Scientific on the many accomplishments of to consider recommendations in the of America’s scientific enterprise Community: Provide supple- my predecessor, Kate Kirby. But following areas: COVID-19 stimulus and put us on a trajectory to emerge mental funding of at least $26 before I speak about APS, I should back on track. -
Thunderkat: the Meerkat Large Survey Project for Image-Plane Radio Transients
ThunderKAT: The MeerKAT Large Survey Project for Image-Plane Radio Transients Rob Fender1;2∗, Patrick Woudt2∗ E-mail: [email protected], [email protected] Richard Armstrong1;2, Paul Groot3, Vanessa McBride2;4, James Miller-Jones5, Kunal Mooley1, Ben Stappers6, Ralph Wijers7 Michael Bietenholz8;9, Sarah Blyth2, Markus Bottcher10, David Buckley4;11, Phil Charles1;12, Laura Chomiuk13, Deanne Coppejans14, Stéphane Corbel15;16, Mickael Coriat17, Frederic Daigne18, Erwin de Blok2, Heino Falcke3, Julien Girard15, Ian Heywood19, Assaf Horesh20, Jasper Horrell21, Peter Jonker3;22, Tana Joseph4, Atish Kamble23, Christian Knigge12, Elmar Körding3, Marissa Kotze4, Chryssa Kouveliotou24, Christine Lynch25, Tom Maccarone26, Pieter Meintjes27, Simone Migliari28, Tara Murphy25, Takahiro Nagayama29, Gijs Nelemans3, George Nicholson8, Tim O’Brien6, Alida Oodendaal27, Nadeem Oozeer21, Julian Osborne30, Miguel Perez-Torres31, Simon Ratcliffe21, Valerio Ribeiro32, Evert Rol6, Anthony Rushton1, Anna Scaife6, Matthew Schurch2, Greg Sivakoff33, Tim Staley1, Danny Steeghs34, Ian Stewart35, John Swinbank36, Kurt van der Heyden2, Alexander van der Horst24, Brian van Soelen27, Susanna Vergani37, Brian Warner2, Klaas Wiersema30 1 Astrophysics, Department of Physics, University of Oxford, UK 2 Department of Astronomy, University of Cape Town, South Africa 3 Department of Astrophysics, Radboud University, Nijmegen, the Netherlands 4 South African Astronomical Observatory, Cape Town, South Africa 5 ICRAR, Curtin University, Perth, Australia 6 University -
Black Holes, out of the Shadows 12.3.20 Amelia Chapman
NASA’s Universe Of Learning: Black Holes, Out of the Shadows 12.3.20 Amelia Chapman: Welcome, everybody. This is Amelia and thanks for joining us today for Museum Alliance and Solar System Ambassador professional development conversation on NASA's Universe of Learning, on Black Holes: Out of the Shadows. I'm going to turn it over to Chris Britt to introduce himself and our speakers, and we'll get into it. Chris? Chris Britt: Thanks. Hello, this is Chris Britt from the Space Telescope Science Institute, with NASA's Universe of Learning. Welcome to today's science briefing. Thank you to everyone for joining us and for anyone listening to the recordings of this in the future. For this December science briefing, we're talking about something that always generates lots of questions from the public: Black holes. Probably one of the number one subjects that astronomers get asked about interacting with the public, and I do, too, when talking about astronomy. Questions like how do we know they're real? And what impact do they have on us? Or the universe is large? Slides for today's presentation can be found at the Museum Alliance and NASA Nationwide sites as well as NASA's Universe of Learning site. All of the recordings from previous talks should be up on those websites as well, which you are more than welcome to peruse at your leisure. As always, if you have any issues or questions, now or in the future, you can email Amelia Chapman at [email protected] or Museum Alliance members can contact her through the team chat app. -
Stellar Death: White Dwarfs, Neutron Stars, and Black Holes
Stellar death: White dwarfs, Neutron stars & Black Holes Content Expectaions What happens when fusion stops? Stars are in balance (hydrostatic equilibrium) by radiation pushing outwards and gravity pulling in What will happen once fusion stops? The core of the star collapses spectacularly, leaving behind a dead star (compact object) What is left depends on the mass of the original star: <8 M⦿: white dwarf 8 M⦿ < M < 20 M⦿: neutron star > 20 M⦿: black hole Forming a white dwarf Powerful wind pushes ejects outer layers of star forming a planetary nebula, and exposing the small, dense core (white dwarf) The core is about the radius of Earth Very hot when formed, but no source of energy – will slowly fade away Prevented from collapsing by degenerate electron gas (stiff as a solid) Planetary nebulae (nothing to do with planets!) THE RING NEBULA Planetary nebulae (nothing to do with planets!) THE CAT’S EYE NEBULA Death of massive stars When the core of a massive star collapses, it can overcome electron degeneracy Huge amount of energy BAADE ZWICKY released - big supernova explosion Neutron star: collapse halted by neutron degeneracy (1934: Baade & Zwicky) Black Hole: star so massive, collapse cannot be halted SN1006 1967: Pulsars discovered! Jocelyn Bell and her supervisor Antony Hewish studying radio signals from quasars Discovered recurrent signal every 1.337 seconds! Nicknamed LGM-1 now called PSR B1919+21 BRIGHTNESS TIME NATURE, FEBRUARY 1968 1967: Pulsars discovered! Beams of radiation from spinning neutron star Like a lighthouse Neutron -
Plasma Modes in Surrounding Media of Black Holes and Vacuum Structure - Quantum Processes with Considerations of Spacetime Torque and Coriolis Forces
COLLECTIVE COHERENT OSCILLATION PLASMA MODES IN SURROUNDING MEDIA OF BLACK HOLES AND VACUUM STRUCTURE - QUANTUM PROCESSES WITH CONSIDERATIONS OF SPACETIME TORQUE AND CORIOLIS FORCES N. Haramein¶ and E.A. Rauscher§ ¶The Resonance Project Foundation, [email protected] §Tecnic Research Laboratory, 3500 S. Tomahawk Rd., Bldg. 188, Apache Junction, AZ 85219 USA Abstract. The main forces driving black holes, neutron stars, pulsars, quasars, and supernovae dynamics have certain commonality to the mechanisms of less tumultuous systems such as galaxies, stellar and planetary dynamics. They involve gravity, electromagnetic, and single and collective particle processes. We examine the collective coherent structures of plasma and their interactions with the vacuum. In this paper we present a balance equation and, in particular, the balance between extremely collapsing gravitational systems and their surrounding energetic plasma media. Of particular interest is the dynamics of the plasma media, the structure of the vacuum, and the coupling of electromagnetic and gravitational forces with the inclusion of torque and Coriolis phenomena as described by the Haramein-Rauscher solution to Einstein’s field equations. The exotic nature of complex black holes involves not only the black hole itself but the surrounding plasma media. The main forces involved are intense gravitational collapsing forces, powerful electromagnetic fields, charge, and spin angular momentum. We find soliton or magneto-acoustic plasma solutions to the relativistic Vlasov equations solved in the vicinity of black hole ergospheres. Collective phonon or plasmon states of plasma fields are given. We utilize the Hamiltonian formalism to describe the collective states of matter and the dynamic processes within plasma allowing us to deduce a possible polarized vacuum structure and a unified physics. -
HUBBLE SPACE TELESCOPE ULTRAVIOLET SPECTROSCOPY of 14 LOW-REDSHIFT QUASARS1 Rajib Ganguly,2 Michael S
A The Astronomical Journal, 133:479Y486, 2007 February # 2007. The American Astronomical Society. All rights reserved. Printed in U.S.A. HUBBLE SPACE TELESCOPE ULTRAVIOLET SPECTROSCOPY OF 14 LOW-REDSHIFT QUASARS1 Rajib Ganguly,2 Michael S. Brotherton,2 Nahum Arav,3 Sara R. Heap,4 Lutz Wisotzki,5 Thomas L. Aldcroft,6 Danielle Alloin,7,8 Ehud Behar,9 Gabriela Canalizo,10 D. Michael Crenshaw,11 Martijn de Kool,12 Kenneth Chambers,13 Gerald Cecil,14 Eleni Chatzichristou,15 John Everett,16,17 Jack Gabel,3 C. Martin Gaskell,18 Emmanuel Galliano,19 Richard F. Green,20 Patrick B. Hall,21 Dean C. Hines,22 Vesa T. Junkkarinen,23 Jelle S. Kaastra,24 Mary Elizabeth Kaiser,25 Demosthenes Kazanas,4 Arieh Konigl,26 Kirk T. Korista,27 Gerard A. Kriss,28 Ari Laor,9 Karen M. Leighly,29 Smita Mathur,30 Patrick Ogle,31 Daniel Proga,32 Bassem Sabra,33 Ran Sivron,34 Stephanie Snedden,35 Randal Telfer,36 and Marianne Vestergaard37 Received 2006 June 27; accepted 2006 October 4 ABSTRACT We present low-resolution ultraviolet spectra of 14 low-redshift (zem P 0:8) quasars observed with the Hubble Space Telescope STIS as part of a Snapshot project to understand the relationship between quasar outflows and luminosity. By design, all observations cover the C iv emission line. Ten of the quasars are from the Hamburg-ESO catalog, three are from the Palomar-Green catalog, and one is from the Parkes catalog. The sample contains a few interesting quasars, including two broad absorption line (BAL) quasars (HE 0143À3535 and HE 0436À2614), one quasar with a mini-BAL (HE 1105À0746), and one quasar with associated narrow absorption (HE 0409À5004).