A broken solar type II radio burst induced by a coronal shock propagating across the streamer boundary

Abstract

We discuss an intriguing type II radio burst that occurred on 2011 March 27. The dynamic spectrum was featured by a sudden break at about 43 MHz on the well-observed harmonic branch. Before the break, the spectrum drifted gradually with a mean rate of about -0.05 MHz/s. Following the break, the spectrum jumped to lower frequencies. The post-break emission lasted for about three minutes. It consisted of an overall slow drift which appeared to have a few fast drift sub-bands. Simultaneous observations from the Solar TErrestrial RElations Observatory (STEREO) and the Solar Dynamics Observatory (SDO) were also available and are examined for this event. We suggest that the slow-drift period before the break was generated inside a streamer by a coronal eruption driven shock, and the spectral break as well as the relatively wide spectrum after the break is a consequence of the shock crossing the streamer boundary where density drops abruptly. It is suggested that this type of radio bursts can be taken as a unique diagnostic tool for inferring the coronal density structure, as well as the radio emitting source region.

12 pages, 5 figures, accepted by ApJ 2012

Cited by in corpus (28)

• Radio signatures of CME-streamer interaction and source diagnostics of type II radio burst
• A solar type II radio burst from CME-coronal ray interaction: simultaneous radio and EUV imaging
• Diagnostics on the source properties of type II radio burst with spectral bumps
• Understanding CME and associated shock in the solar corona by merging multi wavelengths observation
• Solar Physics with the Square Kilometre Array
• The acceleration of high-energy protons at coronal shocks: the effect of large-scale streamer-like magnetic field structures
• Possible role of coronal streamer as magnetically-closed structure in shock-induced energetic electrons and metric type II radio bursts
• Eruption of a plasma blob, associated M-class flare, and large-scale EUV wave observed by SDO
• Flare Generated Shock Wave Propagation Through Solar Coronal Arcade Loops and Associated Type II Radio Burst
• Source Region of the Decameter - Hectometric Type II Radio Burst: Shock - Streamer Interaction Region
• Source Imaging of a Moving Type-IV Solar Radio Burst and its Role in Tracking Coronal Mass Ejection From the Inner to the Outer Corona
• The Acceleration of Energetic Particles at Coronal Shocks and Emergence of a Double Power Law Feature in Particle Energy Spectra
• An Eruptive Hot-Channel Structure Observed at Metric Wavelength as a Moving Type-IV Solar Radio Burst
• A Solar Radio Dynamic Spectrograph with Flexible Temporal-spectral Resolution
• Electron Acceleration at a Coronal Shock Propagating Through a Large-scale Streamer-like Magnetic Field
• Properties of Streamer Wave Events Observed During the STEREO Era
• Fine and superfine structure of Decameter-Hectometer type II burst on 2011 June 7
• Multi-wavelength Observations of a Metric Type-II Event
• Decameter Stationary Type IV Burst in Imaging Observations on the 6th of September 2014
• Quantifying the Magnetic Structure of a Coronal Shock Producing a Type II Radio Burst
• An extreme ultraviolet wave generating upward secondary waves in a streamer-like solar structure
• Electron acceleration and radio emission following the early interaction of two coronal mass ejections
• An imaging study of a complex solar coronal radio eruption
• Shock-wave radio probing of solar wind sources in coronal magnetic fields
• The Broken Lane of a Type II Radio Burst Caused by Collision of a Coronal Shock with a Flare Current Sheet
• Plasma emission induced by ring-distributed energetic electrons in overdense plasmas
• Source location and evolution of a multi-lane type II radio burst
• Multiple shocks generated by the 2024 May 14 coronal mass ejection