Multi-Stranded Coronal Loops: Quantifying Strand Number and Heating Frequency from Simulated Solar Dynamics Observatory (SDO) Atmospheric Imaging Assembly (AIA) Observations
arXiv:2105.12499 · doi:10.1007/s11207-021-01848-8
Abstract
Coronal loops form the basic building blocks of the magnetically closed solar corona yet much is still to be determined concerning their possible fine-scale structuring and the rate of heat deposition within them. Using an improved multi-stranded loop model to better approximate the numerically challenging transition region, this paper examines synthetic NASA Solar Dynamics Observatory's (SDO) Atmospheric Imaging Assembly (AIA) emission simulated in response to a series of prescribed spatially and temporally random, impulsive and localised heating events across numerous sub-loop elements with a strong weighting towards the base of the structure; the nanoflare heating scenario. The total number of strands and nanoflare repetition times are varied systematically in such a way that the total energy content remains approximately constant across all the cases analysed. Repeated time lag detection during an emission time series provides a good approximation for the nanoflare repetition time for low-frequency heating. Furthermore, using a combination of AIA 171/193 and 193/211 channel ratios in combination with spectroscopic determination of the standard deviation of the loop apex temperature over several hours alongside simulations from the outlined multi-stranded loop model, it is demonstrated that both the imposed heating rate and number of strands can be realised.
References in corpus (27)
- Highly Efficient Modeling of Dynamic Coronal Loops
- The influence of numerical resolution on coronal density in hydrodynamic models of impulsive heating
- Structure of solar coronal loops: from miniature to large-scale
- Enthalpy-based Thermal Evolution of Loops: II. Improvements to the Model
- Observations of Active Region Loops with the EUV Imaging Spectrometer on Hinode
- High Spatial Resolution Observations of Loops in the Solar Corona
- Patterns of Nanoflare Storm Heating Exhibited by an Active Region Observed with SDO/AIA
- Observing Episodic Coronal Heating Events Rooted in Chromospheric Activity
- The Width Distribution of Loops and Strands in the Solar Corona -- Are we Hitting Rock Bottom ?
- Modeling the Line-of-Sight Integrated Emission in the Corona: Implications for Coronal Heating
- Unresolved fine-scale structure in solar coronal loop-tops
- An MHD avalanche model of multi-threaded coronal loop
- Is the High-Resolution Coronal Imager Resolving Coronal Strands? Results from AR 12712
- The effects of numerical resolution, heating timescales and background heating on thermal non-equilibrium in coronal loops
- A Fast and Accurate Method to Capture the Solar Corona/Transition Region Enthalpy Exchange
- Inference of Heating Properties from "Hot" Non-flaring Plasmas in Active Region Cores. II. Nanoflare Trains
- Plasma parameters and geometry of cool and warm active region loops
- A new approach for modelling chromospheric evaporation in response to enhanced coronal heating: I The method
- Modelling the solar transition region using an adaptive conduction method
- Understanding Heating in Active Region Cores through Machine Learning I. Numerical Modeling and Predicted Observables
- Signatures of Steady Heating in Time Lag Analysis of Coronal Emission
- Chromospheric evaporation and phase mixing of Alfvén waves in coronal loops
- A new approach for modelling chromospheric evaporation in response to enhanced coronal heating: II Non-uniform heating
- Evidence for and Analysis of Multiple Hidden Coronal Strands in Cross-Sectional Emission Profiles: Further Results from NASA's High-resolution Solar Coronal Imager
- Hydrodynamic Simulation of a nano-flare heated multi-strand solar atmospheric loop
- The Coronal Loop Inventory Project: Expanded Analysis and Results
- EUV Observational consequences of the spatial localisation of nanoflare heating within a multi-stranded atmospheric loop