Physics
Scientific paper
Jan 1992
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1992phdt........28d&link_type=abstract
Ph.D. Thesis North Carolina Univ., Chapel Hill.
Physics
1
Emission Spectra, Fractals, Magnetic Fields, Quasars, Radio Emission, Radio Galaxies, Synchrotron Radiation, Electron Distribution, Electron Energy, Magnetic Field Configurations
Scientific paper
The synchrotron surface brightness of several large angular size radio sources (the radio galaxies Cygnus A (at both 6 and 20 centimeters) 3C436, 3C353 (both at 20 cm) as well as the quasar 3C 175 (at 6 cm)) were analyzed in terms of their fractal properties. All the galaxies show remarkably similar fractal spectra, different from those seen in terrestrial examples of hydrodynamic turbulence. The quasar has a slightly different spectrum, more closely resembling terrestrial examples. To reach a physical interpretation of these results, multifractal models were used to simulate synchrotron radio emission in four different cases: (1) a multifractal distribution of electron energies with uniform magnetic field, (2) a multifractal distribution of magnetic field strengths containing a monoenergetic electron distribution, (3) multifractal distribution of electron number densities with uniform magnetic field, and (4) a power law electron energy distribution in a multifractal distribution of magnetic field strengths. With the additional constraint that the simulations produce the observed synchrotron emission spectrum, the fractal spectra of the simulations were compared to the observed fractal spectra of the radio lobes. Only the quasar was well represented by the fractal spectrum both in terms of the width of the spectrum, and the fractal dimension of the minimum and maximum alpha values. The simulations were too wide, and did not have elevated values for f(alpha(sub min)) even when the magnetic fields fractal spectrum f(alpha(sub min)) values were elevated. Multifractal analysis is shown to be a powerful tool for interpreting the turbulence inside the lobes of radio galaxies and quasars. By comparing the fractal spectra of observed radio lobes at different frequencies, to various simulated multifractal spectra, one can infer details of the lobe physics. This will have implications for numerical magnetohydrodynamic (MHD) simulations of these objects.
No associations
LandOfFree
Multifractal analysis of radio lobes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Multifractal analysis of radio lobes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multifractal analysis of radio lobes will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-939767