Parametric decay of oblique arc-polarized Alfvén waves

• Published in: Geophysical research letters Vol. 28; no. 13; pp. 2585 - 2588
• Main Author: Del Zanna, Luca
• Format: Journal Article
• Language: English
• Published: Washington, DC Blackwell Publishing Ltd 01.07.2001; American Geophysical Union
• Subjects: Astronomy; Earth, ocean, space; Exact sciences and technology; Interplanetary space; Solar system; Solar wind plasma; Alfven waves; Polarization; Parametric instabilities; MHD model; Wave propagation; Digital simulation; One dimensional model; Polarized wave; Decay instability; Oblique propagation; Long term; Solar wind
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2001GL012911

The long‐term nonlinear evolution of monochromatic large‐amplitude Alfvén waves in oblique propagation is studied via one‐dimensional magnetohydrodynamic (MHD) numerical simulations. Arc‐polarized waves, which are exact solutions for non‐parallel propagation and are observed in solar wind data, are shown to be subject to parametric decay instabilities just like the well studied case of circularly polarized waves, not only when arc polarization is used as initial condition but also when this state is reached after nonlinear evolution of linearly polarized waves.