Properties of quasi-periodic pulsations in solar flares from a single active region

Abstract

We investigate the properties of a set of solar flares originating from a single active region (AR) that exhibit QPPs, and look for signs of the QPP periods relating to AR properties. The AR studied, best known as NOAA 12192, was unusually long-lived and produced 181 flares. Data from the GOES, EVE, Fermi, Vernov and NoRH observatories were used to determine if QPPs were present in the flares. For the soft X-ray GOES and EVE data, the time derivative of the signal was used. Power spectra of the time series data (without any form of detrending) were inspected, and flares with a peak above the 95% confidence level in the spectrum were labelled as having candidate QPPs. The confidence levels were determined taking account of uncertainties and the possible presence of red noise. AR properties were determined using HMI line of sight magnetograms. A total of 37 flares (20% of the sample) show good evidence of having QPPs, and some of the pulsations can be seen in data from multiple instruments and in different wavebands. The QPP periods show a weak correlation with the flare amplitude and duration, but this may be due to an observational bias. A stronger correlation was found between the QPP period and duration of the QPP signal, which can be partially but not entirely explained by observational constraints. No correlations were found with the AR area, bipole separation, or average magnetic field strength. The fact that a substantial fraction of the flare sample showed evidence of QPPs using a strict detection method with minimal processing of the data demonstrates that these QPPs are a real phenomenon, which cannot be explained by the presence of red noise or the superposition of multiple unrelated flares. The lack of correlation between the QPP periods and AR properties implies that the small-scale structure of the AR is important, and/or that different QPP mechanisms act in different cases.

arXiv comment23 pages, 57 figures. Accepted for publication by Astronomy & Astrophysics

References in corpus (32)

• The Fermi Gamma-Ray Burst Monitor
• A simple test for periodic signals in red noise
• Temporal aspects and frequency distributions of solar soft X-ray flares
• The Confined X-class Flares of Solar Active Region 2192
• Quasi-periodic pulsations in solar and stellar flares: an overview of recent results
• MHD wave propagation in the neighbourhood of a two-dimensional null point
• How did a Major Confined Flare Occur in Super Solar Active Region 12192?
• Soft X-ray Pulsations in Solar Flares
• A large-scale search for evidence of quasi-periodic pulsations in solar flares
• Quasi-periodic pulsations in solar and stellar flares: re-evaluating their nature in the context of power-law flare Fourier spectra
• On The Fourier And Wavelet Analysis Of Coronal Time Series
• Statistical Properties of Quasi-Periodic Pulsations in White-Light Flares Observed With Kepler
• Three-dimensional oscillatory magnetic reconnection
• Oscillatory processes in solar flares
• Solar Magnetic Feature Detection and Tracking for Space Weather Monitoring
• Modeling the Dispersal of an Active Region: Quantifying Energy Input into the Corona
• Generation of quasi-periodic waves and flows in the solar atmosphere by oscillatory reconnection
• Correlation of hard X-ray and white light emission in solar flares
• Magnetic-Island Contraction and Particle Acceleration in Simulated Eruptive Solar Flares
• Quasi-Periodic Pulsations in Solar Flares: new clues from the Fermi Gamma-Ray Burst Monitor
• Quasi-Periodic Pulsations during the Impulsive and Decay phases of an X-class Flare
• EUV SpectroPhotometer (ESP) in Extreme Ultraviolet Variability Experiment (EVE): Algorithms and Calibrations
• Homologous Jet-Driven Coronal Mass Ejections From Solar Active Region 12192
• Why is a flare-rich active region CME-poor?
• Detection and Interpretation Of Long-Lived X-Ray Quasi-Periodic Pulsations in the X-Class Solar Flare On 2013 May 14
• Study on Precursor Activity of the X1.6 Flare in the Great AR 12192 with SDO, IRIS, and Hinode
• IRIS, Hinode, SDO, and RHESSI observations of a white light flare produced directly by non-thermal electrons
• Spatio-temporal dynamics of sources of hard X-ray pulsations in solar flares
• Significance testing for quasi-periodic pulsations in solar and stellar flares
• Triggering Process of the X1.0 Three-ribbon Flare in the Great Active Region NOAA 12192
• Quasi-periodic pulsations with periods that change depending on whether the pulsations have thermal or nonthermal components
• Stellar flares and the dark energy of CMEs

Cited by in corpus (20)

• Persistent Quasi-Periodic Pulsations During a Large X-Class Solar Flare
• Statistical Study of GOES X-ray Quasi-Periodic Pulsations in Solar Flares
• A blueprint of state-of-the-art techniques for detecting quasi-periodic pulsations in solar and stellar flares
• Quasi-periodic pulsations in the most powerful solar flare of Cycle 24
• On the periodicity of linear and nonlinear oscillatory reconnection
• Oscillatory Reconnection of a 2D X-point in a hot coronal plasma
• Detections of Multi-Periodic Oscillations during a Circular Ribbon Flare
• Novel data analysis techniques in coronal seismology
• Oscillatory reconnection as a plasma diagnostic in the solar corona
• Characterising fast-time variations in the hard X-ray time profiles of solar flares using Solar Orbiter's STIX
• Scaling laws of quasi-periodic pulsations in solar flares
• Multi-waveband detection of quasi-periodic pulsations in a stellar flare on EK Draconis observed by XMM-Newton
• Quasi-periodic pulsations in extreme-ultraviolet brightenings
• Oscillations Accompanying a He I 10830 Å Negative Flare in a Solar Facula II. Response of the Transition Region and Corona
• Oscillations accompanying a He I 10830 Å negative flare in a solar facula
• Stationary quasi-periodic pulsations in 20-second cadence TESS flares
• HEL1OS -- A Hard X-ray Spectrometer on Board Aditya-L1
• Accessing the fine temporal scale of EUV brightenings and their quasi-periodic pulsations: 1 second cadence observations by Solar Orbiter/EUI
• The independence of oscillatory reconnection periodicity from the initial pulse
• Quasi-Periodic Pulsations Detected in Ly$\alpha$ and Nonthermal Emissions During Solar Flares