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Title: A CR-hydro-NEI model of the structure and broadband emission from Tycho's supernova remnant

Tycho's supernova remnant (SNR) is well-established as a source of particle acceleration to very high energies. Constraints from numerous studies indicate that the observed γ-ray emission results primarily from hadronic processes, providing direct evidence of highly relativistic ions that have been accelerated by the SNR. Here we present an investigation of the dynamical and spectral evolution of Tycho's SNR by carrying out hydrodynamical simulations that include diffusive shock acceleration of particles in the amplified magnetic field at the forward shock of the SNR. Our simulations provide a consistent view of the shock positions, the nonthermal emission, the thermal X-ray emission from the forward shock, and the brightness profiles of the radio and X-ray emission. We compare these with the observed properties of Tycho to determine the density of the ambient material, the particle acceleration efficiency and maximum energy, the accelerated electron-to-proton ratio, and the properties of the shocked gas downstream of the expanding SNR shell. We find that evolution of a typical Type Ia supernova in a low ambient density (n {sub 0} ∼ 0.3 cm{sup –3}), with an upstream magnetic field of ∼5 μG, and with ∼16% of the SNR kinetic energy being converted into relativistic electrons and ionsmore » through diffusive shock acceleration, reproduces the observed properties of Tycho. Under such a scenario, the bulk of observed γ-ray emission at high energies is produced by π{sup 0}-decay resulting from the collisions of energetic hadrons, while inverse-Compton emission is significant at lower energies, comprising roughly half of the flux between 1 and 10 GeV.« less
Authors:
;  [1] ; ;  [2] ;  [3] ; ;  [4] ;  [5]
  1. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
  2. RIKEN, Astrophysical Big Bang Laboratory, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)
  3. Physics Department, North Carolina State University, Box 8202, Raleigh, NC 27695 (United States)
  4. Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854-8019 (United States)
  5. MIT-Kavli Center for Astrophysics and Space Research, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)
Publication Date:
OSTI Identifier:
22351452
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 783; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; BRIGHTNESS; COLLISIONS; COSMIC RADIATION; DECAY; DENSITY; EFFICIENCY; ELECTRONS; EMISSION; EVOLUTION; GEV RANGE; IONS; LIMITING VALUES; MAGNETIC FIELDS; PROTONS; RELATIVISTIC RANGE; SHOCK WAVES; SUPERNOVA REMNANTS; X RADIATION