Potential Evidence for the Onset of Alfvénic Turbulence in Trans-equatorial Coronal Loops

Ineke De Moortel, Scott McIntosh, James William Threlfall, Christian Bethge, J Liu

Research output: Contribution to journalArticlepeer-review

17 Citations (Scopus)
3 Downloads (Pure)

Abstract

This study investigates Coronal Multi-channel Polarimeter Doppler-shift observations of a large, off-limb, trans-equatorial loop system observed on 2012 April 10-11. Doppler-shift oscillations with a broad range of frequencies are found to propagate along the loop with a speed of about 500 km s–1. The power spectrum of perturbations travelling up from both loop footpoints is remarkably symmetric, probably due to the almost perfect north-south alignment of the loop system. Compared to the power spectrum at the footpoints of the loop, the Fourier power at the apex appears to be higher in the high-frequency part of the spectrum than expected from theoretical models. We suggest this excess high-frequency power could be tentative evidence for the onset of a cascade of the low-to-mid frequency waves into (Alfvénic) turbulence.
Original languageEnglish
Article numberL34
Number of pages6
JournalAstrophysical Journal Letters
Volume782
Issue number2
DOIs
Publication statusPublished - 10 Feb 2014

Keywords

  • Magnetohydrodynamics (MHD) – Sun
  • Atmosphere - Sun
  • Corona - Sun
  • Oscillations-turbulence-waves

Fingerprint

Dive into the research topics of 'Potential Evidence for the Onset of Alfvénic Turbulence in Trans-equatorial Coronal Loops'. Together they form a unique fingerprint.

Cite this