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Title: Spectral and morphological analysis of the remnant of supernova 1987A with ALMA and ATCA

We present a comprehensive spectral and morphological analysis of the remnant of supernova (SN) 1987A with the Australia Telescope Compact Array (ATCA) and the Atacama Large Millimeter/submillimeter Array (ALMA). The non-thermal and thermal components of the radio emission are investigated in images from 94 to 672 GHz (λ 3.2 mm to 450 μm), with the assistance of a high-resolution 44 GHz synchrotron template from the ATCA, and a dust template from ALMA observations at 672 GHz. An analysis of the emission distribution over the equatorial ring in images from 44 to 345 GHz highlights a gradual decrease of the east-to-west asymmetry ratio with frequency. We attribute this to the shorter synchrotron lifetime at high frequencies. Across the transition from radio to far infrared, both the synchrotron/dust-subtracted images and the spectral energy distribution (SED) suggest additional emission beside the main synchrotron component (S {sub ν}∝ν{sup –0.73}) and the thermal component originating from dust grains at T ∼ 22 K. This excess could be due to free-free flux or emission from grains of colder dust. However, a second flat-spectrum synchrotron component appears to better fit the SED, implying that the emission could be attributed to a pulsar wind nebula (PWN). The residualmore » emission is mainly localized west of the SN site, as the spectral analysis yields –0.4 ≲ α ≲ –0.1 across the western regions, with α ∼ 0 around the central region. If there is a PWN in the remnant interior, these data suggest that the pulsar may be offset westward from the SN position.« less
Authors:
;  [1] ; ;  [2] ; ;  [3] ;  [4] ; ;  [5] ;  [6] ;  [7] ;  [8] ;  [9] ;  [10] ;  [11] ;  [12] ;  [13] ;  [14] ;
  1. International Centre for Radio Astronomy Research (ICRAR), M468, University of Western Australia, Crawley, WA 6009 (Australia)
  2. Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904 (United States)
  3. Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)
  4. Australian Research Council, Centre of Excellence for All-sky Astrophysics (CAASTRO) (Australia)
  5. Department of Astronomy, Oskar Klein Center, Stockholm University, AlbaNova, SE-106 91 Stockholm (Sweden)
  6. CSIRO Astronomy and Space Science, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710 (Australia)
  7. Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium)
  8. Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065 (United States)
  9. Institute for the Environment, Physical Sciences and Applied Mathematics, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG (United Kingdom)
  10. Departamento de Astronomía, Universidad de Valencia, C/Dr. Moliner 50, E-46100 Burjassot (Spain)
  11. Department of Earth and Space Sciences, Chalmers University of Technology, Onsala Space Observatory, SE-439 92 Onsala (Sweden)
  12. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
  13. Department of Physics, University of Hong Kong, Pokfulam Road, Hong Kong (China)
  14. Department of Physics, University of Texas at Arlington, 108 Science Hall, Box 19059, Arlington, TX 76019 (United States)
Publication Date:
OSTI Identifier:
22370173
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 796; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASYMMETRY; DISTRIBUTION; DUSTS; EMISSION; ENERGY SPECTRA; LIFETIME; NEBULAE; PULSARS; RESOLUTION; SUPERNOVA REMNANTS; SUPERNOVAE; SYNCHROTRON RADIATION; TELESCOPES