Observations of a Quasi-periodic, Fast-Propagating Magnetosonic Wave in Multiple Wavelengths and Its Interaction with Other Magnetic Structures

Abstract

We present observations of a quasi-periodic fast-propagating (QFP) magnetosonic wave on 23 April 2012, with high-resolution observations taken by the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory. Three minutes after the start of a C2.0 flare, wave trains were first observed along an open divergent loop system in 171Å observations at a distance of 150 Mm from the footpoint of the guiding loop system and with a speed of 689 km s −1 , then they appeared in 193Å observations after their interaction with a perpendicular, underlaying loop system on the path; in the meantime; their speed decelerated to 343 km s −1 within a short time. The sudden deceleration of the wave trains and their appearance in 193Å observations are interpreted through a geometric effect and the density increase of the guiding loop system, respectively. We find that the wave trains have a common period of 80 seconds with the flare. In addition, a few low frequencies are also identified in the QFP wave. We propose that the generation of the period of 80 seconds was caused by the periodic releasing of energy bursts through some nonlinear processes in magnetic reconnection, while the low frequencies were possibly the leakage of pressure-driven oscillations from the photosphere or chromosphere, which could be an important source for driving coronal QFP waves. Our results also indicate that the properties of the guiding magnetic structure, such as the distributions of magnetic field and density as well as geometry, are crucial for modulating the propagation behaviors of QFP waves.

Observation of a high-quality quasi-periodic rapidly propagating wave train using SDO/AIA

“…Previous works on QFP wave trains Shen et al 2013;Shen & Liu 2012;Yuan et al 2013) showed an intimate connection between the formation and propagation of QFP wave trains and the time variability of the flaring energy release. In particular, of interest are quasi-periodic pulsations (QPP) in the flare light curve.…”

“…The observed disturbances were interpreted in terms of fast magnetoacoustic waves driven quasi-periodically at the base of the flaring region (Ofman et al 2011). Other detailed observations are reported by Shen & Liu (2012) and Shen et al (2013), who demonstrated an intimate association with the flare The movies are available in electronic form at http://www.aanda.org energy releases and the role of magnetic loop structures in guiding these waves. Yuan et al (2013) also observed quasiperiodic propagating fast wave trains associated with flaring radio emission.…”

“…Despite the growing interest in rapidly propagating EUV wave trains in solar coronal structures, their observational detection is rare, with just a few events published in literature Shen & Liu 2012;Shen et al 2013). Thus, any new observation of this phenomenon is very valuable to reveal its nature, validate and further develop the theoretical models.…”

Coronal EUV, QFP, and kink waves simultaneously launched during the course of jet–loop interaction

“…Previous observational studies indicated that the excitation of QFP waves include several possible mechanisms, including 1) the nonlinear energy-releasing processes in the magnetic reconnection process of flares (e.g., Liu et al 2011;Shen & Liu 2012b;Shen et al 2013aShen et al , 2018c, 2) the leakage of photospheric pressure-driven oscillations into the corona (e.g., Shen & Liu 2012b), and 3) the dispersive evolution of an initially broad-band disturbance in inhomogeneous medium (e.g., Nisticò et al 2014;Shen et al 2018b,d). For the present case, by analyzing the periods of the associated flare we find that the periods of the QFP wave and the associated flare showed large difference.…”

Fast magnetoacoustic wave trains in coronal holes

“…The typical apparent (projected) speeds of the disturbances were found to exceed several hundred km s´1, and the periods are several tens of seconds (see e.g. Shen et al 2013, for another recent event). Also, detailed analysis revealed the association of rapidly propagating EUV disturbances with impulsive energy releases (Shen & Liu 2012) and the wave-train nature of the disturbances (Yuan et al 2013).…”