Exploring the intermittency of magnetohydrodynamic turbulence by synchrotron polarization radiation

TL;DR

This paper investigates how synchrotron polarization radiation can be used to analyze the intermittency of magnetohydrodynamic turbulence in astrophysical environments, revealing key properties and regimes of turbulence.

Contribution

It introduces statistical methods to extract turbulence intermittency from observations, demonstrating their effectiveness with synthetic and real data.

Findings

Synchrotron polarization intensity statistics can probe magnetic turbulence intermittency.

Intermittency is dominated by the slow mode in sub-Alfvénic turbulence.

Galactic ISM at low latitudes exhibits sub-Alfvénic and supersonic turbulence regimes.

Abstract

Magnetohydrodynamic (MHD) turbulence plays a critical role in many key astrophysical processes such as star formation, acceleration of cosmic rays, and heat conduction. However, its properties are still poorly understood. We explore how to extract the intermittency of compressible MHD turbulence from the synthetic and real observations. The three statistical methods, namely the probability distribution function, kurtosis, and scaling exponent of the multi-order structure function, are used to reveal the intermittency of MHD turbulence. Our numerical results demonstrate that: (1) the synchrotron polarization intensity statistics can be used to probe the intermittency of magnetic turbulence, by which we can distinguish different turbulence regimes; (2) the intermittency of MHD turbulence is dominated by the slow mode in the sub-Alfv{\'e}nic turbulence regime; (3) the Galactic interstellar medium (ISM) at the low latitude region corresponds to the sub-Alfv\'enic and supersonic turbulence regime. We have successfully measured the intermittency of the Galactic ISM from the synthetic and realistic observations.