Multiple Regions of Nonthermal Quasi-Periodic Pulsations during the Impulsive Phase of a Solar Flare
arXiv:2210.06219 · doi:10.3847/1538-4357/ac997a
Abstract
Flare-associated quasiperiodic pulsations (QPPs) in radio and X-ray wavelengths, particularly those related to nonthermal electrons, contain important information about the energy release and transport processes during flares. However, the paucity of spatially resolved observations of such QPPs with a fast time cadence has been an obstacle for us to further understand their physical nature. Here, we report observations of such a QPP event that occurred during the impulsive phase of a C1.8-class eruptive solar flare using radio imaging spectroscopy data from the Karl G. Jansky Very Large Array (VLA) and complementary X-ray imaging and spectroscopy data. The radio QPPs, observed by the VLA in the 1--2 GHz with a subsecond cadence, are shown as three spatially distinct sources with different physical characteristics. Two radio sources are located near the conjugate footpoints of the erupting magnetic flux rope with opposite senses of polarization. One of the sources displays a QPP behavior with a ~5 s period. The third radio source, located at the top of the postflare arcade, coincides with the location of an X-ray source and shares a similar period of ~25--45 s. We show that the two oppositely polarized radio sources are likely due to coherent electron cyclotron maser (ECM) emission. On the other hand, the looptop QPP source, observed in both radio and X-rays, is consistent with incoherent gyrosynchrotron and bremsstrahlung emission, respectively. We conclude that the concurrent, but spatially distinct QPP sources must involve multiple mechanisms which operate in different magnetic loop systems and at different periods.
arXiv comment19 pages, 12 figures, published in The Astrophysical Journal
References in corpus (54)
- The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
- LOFAR: The LOw-Frequency ARray
- The Fermi Gamma-Ray Burst Monitor
- The Interface Region Imaging Spectrograph (IRIS)
- The Murchison Widefield Array: the Square Kilometre Array Precursor at low radio frequencies
- The Expanded Very Large Array -- a New Telescope for New Science
- Optimization code with weighting function for the reconstruction of coronal magnetic fields
- A Review of Solar Type III Radio Bursts
- Differential Emission Measures from the Regularized Inversion of Hinode and SDO data
- Microwave and Hard X-Ray Observations of the 2017 September 10 Solar Limb Flare
- Modelling Quasi-Periodic Pulsations in Solar and Stellar Flares
- Particle Acceleration by a Solar Flare Termination Shock
- Measurement of magnetic field and relativistic electrons along a solar flare current sheet
- Relationship between wave processes in sunspots and quasi-periodic pulsations in active region flares
- Quasi-periodic pulsations in solar and stellar flares: an overview of recent results
- What can we learn about solar coronal mass ejections, coronal dimmings, and Extreme-Ultraviolet jets through spectroscopic observations?
- Periodic Acceleration of Electrons in the 1998 November 10 Solar Flare
- MHD Sausage Mode Oscillations in Coronal Loops
- Global sausage oscillation of solar flare loops detected by the Interface Region Imaging Spectrograph
- Above-the-loop-top Oscillation and Quasi-periodic Coronal Wave Generation in Solar Flares
- Anisotropic Radio-Wave Scattering and the Interpretation of Solar Radio Emission Observations
- On The Fourier And Wavelet Analysis Of Coronal Time Series
- Observations of sausage modes in magnetic pores
- Tracing Electron Beams in the Sun's Corona with Radio Dynamic Imaging Spectroscopy
- Persistent Quasi-Periodic Pulsations During a Large X-Class Solar Flare
- Statistical Study of GOES X-ray Quasi-Periodic Pulsations in Solar Flares
- Microwave Quasi-periodic Pulsations in Multi-timescales Associated with a Solar Flare/CME Event
- Quasi-Periodic Pulsations in Solar Flares: new clues from the Fermi Gamma-Ray Burst Monitor
- Magnetic Reconnection During the Post-Impulsive Phase of a Long-Duration Solar Flare: Bi-Directional Outflows as a Cause of Microwave and X-ray Bursts
- Microwave Spectral Imaging of an Erupting Magnetic Flux Rope: Implications for the Standard Solar Flare Model in Three Dimensions
- Observations of Solar Coronal Rain in Null Point Topologies
- Quasi-Periodic Pulsations during the Impulsive and Decay phases of an X-class Flare
- Observation of a Quasi-periodic Pulsation in Hard X-ray, Radio and Extreme-ultraviolet Wavelengths
- Magnetic Reconnection Null Points as the Origin of Semi-relativistic Electron Beams in a Solar Jet
- Broadband Quasi-Periodic Radio and X-ray Pulsations in a Solar Flare
- Radio fiber bursts and fast magnetoacoustic wave trains
- Hot Plasma Flows and Oscillations in the Loop-top Region During the September 10 2017 X8.2 Solar Flare
- A Compact Source for Quasi-Periodic Pulsation in an M-class Solar Flare
- The origin of the modulation of the radio emission from the solar corona by a fast magnetoacoustic wave
- Quasi-Periodic Particle Acceleration in a Solar Flare
- 4D Data Cubes from Radio-Interferometric Spectroscopic Snapshot Imaging
- Microwave Quasi-periodic Pulsation with Millisecond Bursts in A Solar Flare on 2011 August 9
- Evidence for Super-Alfvenic oscillations in sources of Solar type III radio bursts
- Modeling of gyrosynchrotron radio emission pulsations produced by MHD loop oscillations in solar flares
- Coronal Mass Ejections and Dimmings: A Comparative Study using MHD Simulations and SDO Observations
- Quasi-periodic wiggles of microwave zebra structures in a solar flare
- Observation of quasi-periodic solar radio bursts associated with propagating fast-mode waves
- Relationship of type III radio bursts with quasi-periodic pulsations in a solar flare
- A weak coronal heating event associated with periodic particle acceleration episodes
- Imaging of the Quiet Sun in the Frequency Range of 20-80 MHz
- Radio seismology of the outer solar corona
- Propagation Effects in Quiet Sun Observations at Meter Wavelengths
- An Observational Study of a "Rosetta-Stone" Solar Eruption
- Kinetic Simulation of the Electron-Cyclotron Maser Instability: Relaxation of Electron Horseshoe Distributions