Understanding the Bizarre Shapes of Radio Supernova Remnants
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Pos(BASH 2013)009 † ∗ [email protected] Speaker
The Progenitor Systems and Explosion Mechanisms of Supernovae PoS(BASH 2013)009 Dan Milisavljevic∗ † Harvard University E-mail: [email protected] Supernovae are among the most powerful explosions in the universe. They affect the energy balance, global structure, and chemical make-up of galaxies, they produce neutron stars, black holes, and some gamma-ray bursts, and they have been used as cosmological yardsticks to detect the accelerating expansion of the universe. Fundamental properties of these cosmic engines, however, remain uncertain. In this review we discuss the progress made over the last two decades in understanding supernova progenitor systems and explosion mechanisms. We also comment on anticipated future directions of research and highlight alternative methods of investigation using young supernova remnants. Frank N. Bash Symposium 2013: New Horizons in Astronomy October 6-8, 2013 Austin, Texas ∗Speaker. †Many thanks to R. Fesen, A. Soderberg, R. Margutti, J. Parrent, and L. Mason for helpful discussions and support during the preparation of this manuscript. c Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. http://pos.sissa.it/ Supernova Progenitor Systems and Explosion Mechanisms Dan Milisavljevic PoS(BASH 2013)009 Figure 1: Left: Hubble Space Telescope image of the Crab Nebula as observed in the optical. This is the remnant of the original explosion of SN 1054. Credit: NASA/ESA/J.Hester/A.Loll. Right: Multi- wavelength composite image of Tycho’s supernova remnant. This is associated with the explosion of SN 1572. Credit NASA/CXC/SAO (X-ray); NASA/JPL-Caltech (Infrared); MPIA/Calar Alto/Krause et al. -
Quasistellar Objects: Overview ENCYCLOPEDIA of ASTRONOMY and ASTROPHYSICS
eaa.iop.org DOI: 10.1888/0333750888/1585 Quasistellar Objects: Overview Patrick Osmer From Encyclopedia of Astronomy & Astrophysics P. Murdin © IOP Publishing Ltd 2006 ISBN: 0333750888 Institute of Physics Publishing Bristol and Philadelphia Downloaded on Thu Mar 02 22:43:08 GMT 2006 [131.215.103.76] Terms and Conditions Quasistellar Objects: Overview ENCYCLOPEDIA OF ASTRONOMY AND ASTROPHYSICS Quasistellar Objects: Overview Quasistellar objects, or quasars, were defined originally as star-like objects of large redshift. Quasars are believed to be powered by the accretion of matter onto massive black holes at the centers of galaxies, a process that emits more energy than thermonuclear reactions. Today, quasars are considered to be the most luminous members of the general class of objects called active galactic nuclei, or AGNs. Quasars are the most luminous objects in the universe. This article begins with a brief history of the discovery of quasars. Next it describes their main properties and the concepts that have been developed to explain them. It continues with a description of their nature and theoretical models. Then additional properties and topics are considered: absorption lines, host galaxies, Figure 1. Optical image of 3C273. The object looks stellar in and luminosity functions and evolution. this image except that it is accompanied by a jet of radiation extending to the lower right. (Credit National Optical Astronomy Observatories/National Science Foundation. History Copyright Association of Universities for Research in In 1960 Mathews and Sandage identified the radio source Astronomy Inc (AURA), all rights reserved.) 3C 48 (the 48th object in the 3rd Cambridge catalog of radio sources) with a star-like object of 16th magnitude. -
Pos(Westerbork)006 S 4.0 International License (CC BY-NC-ND 4.0)
Exploring the time-varying Universe PoS(Westerbork)006 Richard Strom ASTRON Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands E-mail: [email protected] Lodie Voûte ASTRON, Anton Pannekoek Inst. Of Astronomy, University of Amsterdam, Postbus 94249, 1090 GE Amsterdam, The Netherlands E-mail: [email protected] Benjamin Stappers School of Phys. & Astron., Alan Turing Bldg., University of Manchester, Oxford Road, Manchester M13 9PL, UK E-mail: [email protected] Gemma Janssen ASTRON Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands E-mail: [email protected] Jason Hessels ASTRON Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands E-mail: [email protected] 50 Years Westerbork Radio Observatory, A Continuing Journey to Discoveries and Innovations Richard Strom, Arnold van Ardenne, Steve Torchinsky (eds) Published with permission of the Netherlands Institute for Radio Astronomy (ASTRON) under the terms of the Creative CommonsAttribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). Exploring the time-varying Universe Chapter 5.1 The earliest start Richard Strom* Introduction The WSRT interferometrically measures Fourier components of the sky bright- ness distribution from a region set by the primary beam of the telescope ele- ments, at a radio frequency determined by the receiver. This information is used to construct a two-dimensional image of radio emission from the piece of sky observed. Because it is an east-west interferometer array, the information obtained at any instant of time can only be used to construct a one-dimensional map (the telescope so synthesized has the response of a fan beam – narrow in one direction, but orthogonally very elongated). -
Blasts from the Past Historic Supernovas
BLASTS from the PAST: Historic Supernovas 185 386 393 1006 1054 1181 1572 1604 1680 RCW 86 G11.2-0.3 G347.3-0.5 SN 1006 Crab Nebula 3C58 Tycho’s SNR Kepler’s SNR Cassiopeia A Historical Observers: Chinese Historical Observers: Chinese Historical Observers: Chinese Historical Observers: Chinese, Japanese, Historical Observers: Chinese, Japanese, Historical Observers: Chinese, Japanese Historical Observers: European, Chinese, Korean Historical Observers: European, Chinese, Korean Historical Observers: European? Arabic, European Arabic, Native American? Likelihood of Identification: Possible Likelihood of Identification: Probable Likelihood of Identification: Possible Likelihood of Identification: Possible Likelihood of Identification: Definite Likelihood of Identification: Definite Likelihood of Identification: Possible Likelihood of Identification: Definite Likelihood of Identification: Definite Distance Estimate: 8,200 light years Distance Estimate: 16,000 light years Distance Estimate: 3,000 light years Distance Estimate: 10,000 light years Distance Estimate: 7,500 light years Distance Estimate: 13,000 light years Distance Estimate: 10,000 light years Distance Estimate: 7,000 light years Distance Estimate: 6,000 light years Type: Core collapse of massive star Type: Core collapse of massive star Type: Core collapse of massive star? Type: Core collapse of massive star Type: Thermonuclear explosion of white dwarf Type: Thermonuclear explosion of white dwarf? Type: Core collapse of massive star Type: Thermonuclear explosion of white dwarf Type: Core collapse of massive star NASA’s ChANdrA X-rAy ObServAtOry historic supernovas chandra x-ray observatory Every 50 years or so, a star in our Since supernovas are relatively rare events in the Milky historic supernovas that occurred in our galaxy. Eight of the trine of the incorruptibility of the stars, and set the stage for observed around 1671 AD. -
Science Highlights
>>> SCIENCENOAO/NSO HIGHLIGHTS Echoes of Galactic Supernovae Armin Rest (Harvard University) & Chris Smith (NOAO) for the Echoes of Historical Supernovae (EHS) Team ight echoes from ancient supernova offer a unique and powerful oppor- tunity to study supernovae and their Lrelationships to supernova remnants (SNRs), as well as interstellar dust and Galactic structure. The use of this relatively simple phenomenon of light echoes in such studies is just now developing into an exciting new field of study. This is one of the very rare occasions in astronomy that the cause and effect of the same astronomical event can be observed, in that we can study the physics of the SNR as it appears now and also the physics of the explosion that produced it hundreds of years ago. We define a light echo as reflected light from a light source, not reprocessed light. Similar to the muffled echo of sound when someone shouts something toward a wall, the light echo still contains the initial signature of the original light, even if the precise signa- ture is somewhat modified by details of the reflecting surface. Since the reflected light traverses a longer path than the light that takes the direct path to the observer, it will be Figure 1 observed some time after the initial explosion is observed. to the SNR may be tens of times larger than if the Galactic plane than the supernovae in the the same SN and reflecting dust were located expectation that dust would be more highly Our group pioneered the optical discovery in the LMC. Thus the search annuli for light concentrated there. -
Shell Supernova Remnants As Cosmic Accelerators: I Stephen Reynolds, North Carolina State University
Shell supernova remnants as cosmic accelerators: I Stephen Reynolds, North Carolina State University I. Overview II. Supernovae: types, energies, surroundings III.Dynamics of supernova remnants A)Two-shock (ejecta-dominated) phase B)Adiabatic (Sedov) phase C)Transition to radiative phase IV. Diffusive shock acceleration V. Radiative processes SLAC Summer Institute August 2008 Supernova remnants for non-astronomers Here: ªSNRº means gaseous shell supernova remnant. Exploding stars can also leave ªcompact remnants:º -- neutron stars (which may or may not be pulsars) -- black holes We exclude pulsar-powered phenomena (ªpulsar-wind nebulae,º ªCrablike supernova remnantsº after the Crab Nebula) SN ejects 1 ± 10 solar masses (M⊙) at high speed into surrounding material, heating to X-ray emitting temperatures (> 107 K). Expansion slows over ~105 yr. Young (ªadiabatic phaseº) SNRs: t < tcool ~ 10,000 yr. Observable primarily through radio (synchrotron), X-rays (if not absorbed by intervening ISM) Older (ªradiative phaseº): shocks are slow, highly compressive; bright optical emission. (Still radio emitters, maybe faint soft X-rays). SLAC Summer Institute August 2008 SNRs: background II Supernovae: visible across Universe for weeks ~ months SNRs: detectable only in nearest galaxies, but observable for 104 ± 105 yr So: almost disjoint sets. Important exception: Historical supernovae. Chinese, European records document ªnew starsº visible with naked eye for months. In last two millenia: 185 CE, 386, 393, 1006, 1054 (Crab Nebula), 1181 (?), 1572 (Tycho©s SN), 1604 (Kepler©s SN) ªQuasi-historical:º deduced to be < 2000 yr old, but not seen due to obscuration: Cas A (~ 1680), G1.9+0.3 (~ 1900). Unique testbed: SN 1987A (Large Magellanic Cloud) SLAC Summer Institute August 2008 A supernova-remnant gallery 1. -
Nature's Biggest Explosions: Past, Present, and Future
Nature’s Biggest Explosions: Past, Present, and Future Edo Berger Harvard University Why Study Cosmic Explosions? Why Study Cosmic Explosions? Why Study Cosmic Explosions? Why Study Cosmic Explosions? Why Study Cosmic Explosions? The Past About 10 “guest stars” have been mentioned in historical records, spanning from 185 to 1604 AD. All were observed with the naked eye (first telescope was built in 1608 AD). “Throughout all past time, according to the records handed down from generation to generation, nothing is observed to have changed either in the whole of the outermost heaven or in any of its proper parts.” Aristotle, De caelo (On the Heavens), 350 BC SN 185 In 185 AD Chinese records mark the appearance of a “guest star” which remained visible for 8 months and did not move like a planet or a comet. This is the oldest record of a supernova. “In the 2nd year of the epoch Zhongping, the 10th month, on the day Kwei Hae, a strange star appeared in the middle of Nan Mun … In the 6th month of the succeeding year it disappeared.” SN 1006 On April 1006 records from Europe, the Middle East, and Asia mark the appearance of the brightest “guest star” ever seen: bright as a quarter moon and visible during the day. It remained visible for almost 2 years. “…spectacle was a large circular body, 2½ to 3 times as large as Venus. The sky was shining because of its light. The intensity of its light was a little more than the light of the Moon when one-quarter illuminated" SN 1054 On July 4, 1054 AD records from the Middle East and Asia (and potentially North America) mark the appearance of a bright “guest star”; as bright as a 1/16 moon and remained visible for 2 years. -
A Brief History of Astronomical Brightness Determination Methods at Optical Wavelengths
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server A Brief History of Astronomical Brightness Determination Methods at Optical Wavelengths Kevin Krisciunas Abstract In this brief article I review the history of astronomical photometry, touching on observations made by the ancient Chinese, Hipparchus and Ptolemy, the development of the concept (and definition) of magnitude, the endeavors of Argelander and Z¨ollner, work at Harvard at the end of the 19th century, and the development of photography, photomultipliers, and CCD’s and their application to astronomy. ...this brave o'erhanging firmament, this majestical roof fretted with golden fire.... Hamlet, II, ii, 308-310 The following introduction to photometry served as Chapter 1 to my recent University of Washington Dissertation; see Krisciunas (2001) for a summary. Chapter 2 (Krisciunas, Margon, & Szkody 1998) dealt with the identification of objects of interest, in particular RR Lyrae stars, carbon stars, asteroids, and cataclysmic variables, using the photometric system being used for the Sloan Digital Sky Survey. Chapter 3 involved the confirmation of RR Lyrae candidates from SDSS as bona fide RR Lyrae stars; light curves of six of these can be found in Ivezic et al. (2000). Chapters 4 and 5 (Krisciunas et al. 2000, 2001) dealt 1 with Type Ia supernovae and the use of optical and infrared photometry to determine the extinction of these objects attributable to dust along the line of sight. The first systematic observations of the heavens which can be considered “scientific” in any sense were carried out by the Chinese as early as the 14th century BC (Needham & Ling 1959, p. -
An Aboriginal Australian Record of the Great Eruption of Eta Carinae
Accepted in the ‘Journal for Astronomical History & Heritage’, 13(3): in press (November 2010) An Aboriginal Australian Record of the Great Eruption of Eta Carinae Duane W. Hamacher Department of Indigenous Studies, Macquarie University, NSW, 2109, Australia [email protected] David J. Frew Department of Physics & Astronomy, Macquarie University, NSW, 2109, Australia [email protected] Abstract We present evidence that the Boorong Aboriginal people of northwestern Victoria observed the Great Eruption of Eta (η) Carinae in the nineteenth century and incorporated the event into their oral traditions. We identify this star, as well as others not specifically identified by name, using descriptive material presented in the 1858 paper by William Edward Stanbridge in conjunction with early southern star catalogues. This identification of a transient astronomical event supports the assertion that Aboriginal oral traditions are dynamic and evolving, and not static. This is the only definitive indigenous record of η Carinae’s outburst identified in the literature to date. Keywords: Historical Astronomy, Ethnoastronomy, Aboriginal Australians, stars: individual (η Carinae). 1 Introduction Aboriginal Australians had a significant understanding of the night sky (Norris & Hamacher, 2009) and frequently incorporated celestial objects and transient celestial phenomena into their oral traditions, including the sun, moon, stars, planets, the Milky Way and Magellanic Clouds, eclipses, comets, meteors, and impact events. While Australia is home to hundreds of Aboriginal groups, each with a distinct language and culture, few of these groups have been studied in depth for their traditional knowledge of the night sky. We refer the interested reader to the following reviews on Australian Aboriginal astronomy: Cairns & Harney (2003), Clarke (1997; 2007/2008), Fredrick (2008), Haynes (1992; 2000), Haynes et al. -
Appendix II. Publications
Publications Gemini Staff Publications Papers in Peer-Reviewed Journals: Bergmann, M.[2]. Gemini 3D spectroscopy of BAL+IR+FeII QSOs - II. IRAS 04505-2958, an explosive QSO with hypershells and a new scenario for galaxy formation and galaxy end phase. Monthly Notices of the Royal Astronomical Society, 398:658-700. 9/2009. McDermid, Richard M.[8]. Stellar velocity profiles and line strengths out to four effective radii in the early-type galaxies NGC3379 and 821. Monthly Notices of the Royal Astronomical Society, 398:561-574. 9/2009. Levenson, N. A.[1]; Radomski, J. T.[2]; Mason, R. E.[4]. Isotropic Mid-Infrared Emission from the Central 100 pc of Active Galaxies. The Astrophysical Journal, 703:390-398. 9/2009. Radomski, J. T.[6]; Fisher, R. S.[8]. The Infrared Nuclear Emission of Seyfert Galaxies on Parsec Scales: Testing the Clumpy Torus Models. The Astrophysical Journal, 702:1127-1149. 9/2009. Leggett, S. K.[2]; Geballe, T. R.[6]. The 0.8-14.5 μm Spectra of Mid-L to Mid-T Dwarfs: Diagnostics of Effective Temperature, Grain Sedimentation, Gas Transport, and Surface Gravity. The Astrophysical Journal, 702:154-170. 9/2009. Rantakyro, F.[11]. Cyclic variability of the circumstellar disk of the Be star ζ Tauri. I. Long-term monitoring observations. Astronomy and Astrophysics, 504:929-944. 9/2009. Artigau, E.[10]; Hartung, M.[11]. A deep look into the core of young clusters. II. λ- Orionis. Astronomy and Astrophysics, 504:199-209. 9/2009. West, Michael J.[19]. The XMM Cluster Survey: forecasting cosmological and cluster scaling- relation parameter constraints. -
RADIO STARS and THEIR LIVES in the GALAXY Lynn D
Accepted to PASP A Preprint typeset using LTEX style emulateapj v. 12/16/11 RADIO STARS AND THEIR LIVES IN THE GALAXY Lynn D. Matthews1 Accepted to PASP ABSTRACT This paper summarizes the three-day international workshop Radio Stars and Their Lives in the Galaxy, held at the Massachusetts Institute of Technology Haystack Observatory on 2012 October 3-5. The workshop was organized to provide a forum for the presentation and discussion of advances in stellar and solar astrophysics recently (or soon to be) enabled by the latest generation of state-of-the- art observational facilities operating from meter to submillimeter wavelengths. The meeting brought together both observers and theorists to discuss how radio wavelength observations are providing new and unique insights into the workings of stars and their role in the Galactic ecosystem. Topics covered included radio emission from hot and cool stars (from the pre- to post-main-sequence), the Sun as a radio star, circumstellar chemistry, planetary nebulae, white dwarf binaries and novae, supernova progenitors, and radio stars as probes of the Galaxy. Subject headings: meeting summary, Stars — stars: AGB and post-AGB – stars: winds, outflows – circumstellar matter – radio lines: stars 1. BACKGROUND AND MOTIVATION FOR THE precision astrometry, and the routine study of sources at WORKSHOP a level of a few tens of µJy. We also heard how develop- Radio emission has now been detected from stars ments in theory, modeling, and laboratory astrophysics across the entire Hertzsprung-Russell (H-R) diagram, are improving our ability to interpret results. This paper spanning virtually every stage of stellar evolution. -
D.A. Frail CV Page 1 CURRICULUM VITAE DALE ANDREW FRAIL
CURRICULUM VITAE DALE ANDREW FRAIL National Radio Astronomy Observatory Socorro, NM 87801 (575) 835-7338 [email protected] Education: 1989 – Ph.D. in Astronomy, University of Toronto 1985 – M.Sc. in Astronomy, University of Toronto Current Position: NRAO Astronomer (tenured) Research Interests: - electromagnetic counterparts of gravitational waves - the origin of gamma ray bursts and soft gamma ray repeaters - time-domain astronomy with an emphasis on the dynamic radio sky - pulsars, supernova remnant associations and pulsar wind nebulae - the 1720 MHz OH maser line toward supernova remnants - HI absorption and interstellar scattering Professional Experience: 1999-Present: Astronomer, NRAO 2019-2020: Interim Assistant Director, Science Support and ResearcH (12 mo) 2016 Visiting Associate in Astronomy, Caltech 2011-2015: Assistant Director, New MeXico Operations, VLA and VLBA 2011: Visiting Scientist, Harvard Smithsonian Center for AstropHysics (CfA) 2010: Visiting Scientist, Weizmann Institute of Science 2006-2009: Assistant Director, Science and Academic Affairs, NRAO 2001-2002: Visiting Associate in Astronomy, CaltecH 1995-1999: Associate Astronomer, NRAO 1993-1995: Assistant Astronomer, NRAO 1990–1993: Jansky Fellow, NRAO 1989-1991: NSERC Postdoctoral Fellow Professional and NRAO Service (since 2010): 2020 TIFR-NCRA Visiting Committee (February 2020) Reviewer for the MeerKAT Large Science Proposal reports 2019 Red Team for Fermi NASA Senior Review Proposal review for GMRT, MeerKAT, German-Israel Foundation Referee for ApJ, PASP Astronomer Performance Review Committee (APRC; ad hoc) Member of Jansky Postdoc Selection Committee (last year) 2018 Chandra User’s Committee (CUC; ends Oct. 2018) Promotion Cases (Michigan, CaltecH, TIFR/NCRA) Referee for MNRAS, A&A, ApJ & Nature External eXaminer for K. AleXander PHD at Harvard D.A.