The nature of small scale EUV solar brightenings investigated as impulsive heating of short loops in 1D hydrododynamics simulations
arXiv:2505.07520 · doi:10.1051/0004-6361/202554451
Abstract
Small (400 to 4000 km) and short lived (10 to 200 km) extreme ultraviolet (EUV) brightenings, detected by the High Resolution Imager EUV (HRIEUV), have been found to be ubiquitous in the Quiet Sun (QS). Their contribution to coronal heating as well as their physical origin are currently being investigated. We wish to determine whether models of short loops and impulsive heating are compatible with the results from observations. In particular, we used two models of loops with distinct thermal properties: cool (T below 1E5 K) and hot loops (T above 1E5 K). We simulated the evolution of impulsively heated short loops, using the 1D hydrodynamics (HD) code HYDRAD. We computed the synthetic light curves of HRIEUV, four EUV channels of the Atmospheric Imaging Assembly (AIA), and five emission lines measured by the SPectral Imaging of the Coronal Environment (SPICE). We then compared the results from the synthetic light curves with observations. The aim was to reproduce the short delays observed between the intensity peaks of the light curves. Cool loops subjected to impulsive heating are good candidates to explain the physical origin of the EUV brightenings. On the other hand, hot loops are not consistent with observations, except when they are subjected to especially strong impulsive heating.
arXiv comment27 pages, 20 figures, accepted in A&A, language editing
References in corpus (28)
- The Interface Region Imaging Spectrograph (IRIS)
- The Solar Orbiter mission -- Science overview
- On Solving the Coronal Heating Problem
- CHIANTI -- an atomic database for emission lines -- Paper XVI: Version 10, further extensions
- Highly Efficient Modeling of Dynamic Coronal Loops
- An Ab Initio Approach to the Solar Coronal Heating Problem
- Key Aspects of Coronal Heating
- Coronal heating by MHD waves
- Convectively driven vortex flows in the Sun
- RHESSI Microflare Statistics II. X-ray Imaging, Spectroscopy & Energy Distributions
- An Ab Initio approach to Solar Coronal Loops
- Coronal heating through braiding of magnetic field lines
- The Unresolved Fine Structure Resolved - IRIS observations of the Solar Transition Region
- The Solar Orbiter Science Activity Plan: translating solar and heliospheric physics questions into action
- Transient small-scale brightenings in the quiet solar corona: a model for campfires observed with Solar Orbiter
- Can Thermal Nonequilibrium Explain Coronal Loops?
- Ubiquitous rotating network magnetic fields and EUV cyclones in the quiet Sun
- Inference of Heating Properties from "Hot" Non-flaring Plasmas in Active Region Cores I. Single Nanoflares
- The magnetic drivers of campfires seen by the Polarimetric and Helioseismic Imager (PHI) on Solar Orbiter
- Temperature of Solar Orbiter/EUI quiet Sun small scale brightenings: evidence for a cooler component
- UV and EUV Emissions at the Flare Foot-points Observed by AIA
- Imaging and spectroscopic observations of extreme-ultraviolet brightenings using EUI and SPICE on board Solar Orbiter
- EUV brightenings in the quiet-Sun: Signatures in spectral and imaging data from the Interface Region Imaging Spectrograph
- Spectroscopic evidence of cool plasma in quiet Sun HRIEUV small scale brightenings
- Solar low-lying cool loops and their contribution to the transition region EUV output
- Spatial distributions of EUV brightenings in the quiet-Sun
- Small-scale loops heated to transition region temperatures and their chromospheric signatures in the simulated solar atmosphere
- Investigating explosive events in a 3D quiet-Sun model: Transition region and coronal response