RADIO SYNCHROTRON FLUCTUATION STATISTICS AS A PROBE OF MAGNETIZED INTERSTELLAR TURBULENCE

Journal Article · Sun May 01 00:00:00 EDT 2016 · Astrophysical Journal

DOI:https://doi.org/10.3847/0004-637X/822/1/13· OSTI ID:22663081

Herron, C. A.; Gaensler, B. M. ^[1]; Burkhart, Blakesley ^[2]; Lazarian, A. ^[3]

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1. Sydney Institute for Astronomy, School of Physics, University of Sydney, New South Wales 2006 (Australia)
2. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA (United States)
3. Astronomy Department, University of Wisconsin, Madison, 475 N. Charter Street, WI 53711 (United States)

We investigate how observations of synchrotron intensity fluctuations can be used to probe the sonic and Alfvénic Mach numbers of interstellar turbulence, based on mock observations performed on simulations of magnetohydrodynamic turbulence. We find that the structure function slope and a diagnostic of anisotropy that we call the integrated quadrupole ratio modulus both depend on the Alfvénic Mach number. However, these statistics also depend on the orientation of the mean magnetic field in the synchrotron emitting region relative to our line of sight, and this creates a degeneracy that cannot be broken by observations of synchrotron intensity alone. We conclude that the polarization of synchrotron emission could be analyzed to break this degeneracy, and suggest that this will be possible with the Square Kilometre Array.

• OSTI ID: 22663081
• Journal Information: Astrophysical Journal, Vol. 822, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ALFVEN WAVES
ANISOTROPY
DATA ANALYSIS
EMISSION
FLUCTUATIONS
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
POLARIZATION
QUADRUPOLES
SIMULATION
STATISTICS
STRUCTURE FUNCTIONS
SYNCHROTRONS
TURBULENCE