Simulating Solar Flare Irradiance with Multithreaded Models of Flare Arcades

Abstract

Understanding how energy is released in flares is one of the central problems of solar and stellar astrophysics. Observations of high temperature flare plasma hold many potential clues as to the nature of this energy release. It is clear, however, that flares are not composed of a few impulsively heated loops, but are the result of heating on many small-scale threads that are energized over time, making it difficult to compare observations and numerical simulations in detail. Several previous studies have shown that it is possible to reproduce some aspects of the observed emission by considering the flare as a sequence of independently heated loops, but these studies generally focus on small-scale features while ignoring the global features of the flare. In this paper, we develop a multithreaded model that encompasses the time-varying geometry and heating rate for a series of successively-heated loops comprising an arcade. To validate, we compare with spectral observations of five flares made with the MinXSS CubeSat as well as light curves measured with GOES/XRS and SDO/AIA. We show that this model can successfully reproduce the light curves and quasi-periodic pulsations in GOES/XRS, the soft X-ray spectra seen with MinXSS, and the light curves in various AIA passbands. The AIA light curves are most consistent with long duration heating, but elemental abundances cannot be constrained with the model. Finally, we show how this model can be used to extrapolate to spectra of extreme events that can predict irradiance across a wide wavelength range including unobserved wavelengths.

arXiv commentAccepted to ApJ. v2: Mistake in temperature plots in Figure 1 corrected

References in corpus (41)

• The chemical composition of the Sun
• An Observational Overview of Solar Flares
• Global Energetics of Thirty-Eight Large Solar Eruptive Events
• Implications of X-ray Observations for Electron Acceleration and Propagation in Solar Flares
• Highly Efficient Modeling of Dynamic Coronal Loops
• CHIANTI - an atomic database for emission lines - Paper XV: Version 9, improvements for the X-ray satellite lines
• Modelling Quasi-Periodic Pulsations in Solar and Stellar Flares
• Magnetic Properties of Solar Active Regions that Govern Large Solar Flares and Eruptions
• A Database of Flare Ribbon Properties From Solar Dynamics Observatory I: Reconnection Flux
• The influence of numerical resolution on coronal density in hydrodynamic models of impulsive heating
• The Radiated Energy Budget of Chromospheric Plasma in a Major Solar Flare Deduced From Multi-Wavelength Observations
• Multi-Thread Hydrodynamic Modeling of a Solar Flare
• Soft X-ray Pulsations in Solar Flares
• A large-scale search for evidence of quasi-periodic pulsations in solar flares
• Data-driven Radiative Hydrodynamic Modeling of the 2014 March 29 X1.0 Solar Flare
• Persistent Quasi-Periodic Pulsations During a Large X-Class Solar Flare
• Time delays in quasi-periodic pulsations observed during the X2.2 solar flare on 2011 February 15
• The Thermal Properties of Solar Flares Over Three Solar Cycles Using GOES X-ray Observations
• Measurements of Absolute Abundances in Solar Flares
• Miniature X-Ray Solar Spectrometer (MinXSS) - A Science-Oriented, University 3U CubeSat
• Inference of Heating Properties from "Hot" Non-flaring Plasmas in Active Region Cores I. Single Nanoflares
• The Instruments and Capabilities of the Miniature X-ray Solar Spectrometer (MinXSS) CubeSats
• Reconnection fluxes in eruptive and confined flares and implications for superflares on the Sun
• New Solar Irradiance Measurements from the Miniature X-Ray Solar Spectrometer CubeSat
• Pulsations in the Earth's Lower Ionosphere Synchronized with Solar Flare Emission
• A parameter study for modeling MgII h and k emission during solar flares
• Heating of Flare Loops With Observationally Constrained Heating Functions
• Solar Flare Element Abundances from the Solar Assembly for X-rays (SAX) on MESSENGER
• Detection and Interpretation Of Long-Lived X-Ray Quasi-Periodic Pulsations in the X-Class Solar Flare On 2013 May 14
• What determines the X-ray intensity and duration of a solar flare?
• Transition Region and Chromospheric Signatures of Impulsive Heating Events. II. Modeling
• On the sensitivity of the GOES flare classification to properties of the electron beam in the thick target model
• Determining Heating Rates in Reconnection Formed Flare Loops of the M8.0 Flare on 2005 May 13
• The direct relation between the duration of magnetic reconnection and the evolution of GOES light curves in solar flares
• Two-Phase Heating in Flaring Loops
• The Duration of Energy Deposition on Unresolved Flaring Loops in the Solar Corona
• Statistical Properties of Ribbon Evolution and Reconnection Electric Fields in Eruptive and Confined Flares
• Study of multi-periodic coronal pulsations during an X-class solar flare
• Evidence of Significant Energy Input in the Late Phase of a Solar Flare from NuSTAR X-Ray Observations
• Scaling laws of quasi-periodic pulsations in solar flares
• On excited frequencies for Alfvén waves in a coronal arcade

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• The Lyman-alpha Emission in Solar Flares. I. a Statistical Study on Its Relationship with the 1--8 Å Soft X-ray Emission
• Solar Flare Irradiance: Observations and Physical Modeling
• Radiative Hydrodynamic Simulations of the Spectral Characteristics of Solar White-light Flares
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