Asymmetry of the spectral lines of the coronal hole and quiet Sun in the transition region
arXiv:2402.01628 · doi:10.1093/mnras/stae356
Abstract
The asymmetry of line profiles, i.e., the secondary component, is crucial to understanding the energy release of coronal holes (CH), quiet sun (QS), and bright points (BPs). We investigate the asymmetry of Si IV 1393.75 Å of the transition-region (TR) line recorded by Interface Region Imaging Spectrometer (IRIS) and co-spatial-temporal Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager (HMI) data onboard Solar Dynamics Observatory (SDO) for three time series on 26 April 2015, 24 July 2014, 26 July 2014. Most asymmetric profiles are in the complex magnetic field regions of the networks. The asymmetric profiles are fitted with both single and double Gaussian models. The mean value of Doppler velocity of the second component is almost zero (with a significant standard deviation) in QS/CH, which may indicate that the physical process to trigger the secondary Gaussian originates at the formation height of Si IV. While the mean Doppler velocity from secondary Gaussian in BPs is around +4.0 km/s (redshifted). The non-thermal velocities of the secondary Gaussian in all three regions are slightly higher than the single Gaussian. The statistical investigation leads to the prevalence of blueshifted secondary components in QS/CH. However, secondary Gaussian in the BPs redshifted, i.e., the BPs redshift behavior could be interpreted due to the site of reconnection located above the formation height of the Si IV line. The peak intensity of the second component for all three regions is likely to follow a power law that is a signature of the small-scale flaring-like trigger mechanism.
arXiv commentpublished in Monthly Notices of the Royal Astronomical Society 22 pages, 7 figures in main text, 6 figures in Appendix A and 6 figures in Appendix B
References in corpus (44)
- Power-law distributions in empirical data
- Power laws, Pareto distributions and Zipf's law
- The Interface Region Imaging Spectrograph (IRIS)
- On Solving the Coronal Heating Problem
- Coronal Holes
- Prevalence of Small-scale Jets from the Networks of the Solar Transition Region and Chromosphere
- Observing the Roots of Solar Coronal Heating - in the Chromosphere
- Power laws and Self-Organized Criticality in Theory and Nature
- Solar UV and X-Ray Spectral Diagnostics
- 25 Years of Self-Organized Criticality: Solar and Astrophysics
- Forward modeling of stellar coronae: from a 3D MHD model to synthetic EUV spectra
- High-resolution Observations of the Shock Wave Behavior for Sunspot Oscillations with the Interface Region Imaging Spectrograph
- Interchange reconnection as the source of the fast solar wind within coronal holes
- Characterization of the frequency of extreme events by the Generalized Pareto Distribution
- Asymmetries of solar coronal extreme ultraviolet emission lines
- Ubiquitous High Speed Transition Region and Coronal Upflows in the Quiet Sun
- Iris si iv line profiles: An indication for the plasmoid instability during small-scale magnetic reconnection on the sun
- Coronal hole boundaries evolution at small scales: II. XRT view Can small-scale outflows at CHBs be a source of the slow solar wind?
- Observing Episodic Coronal Heating Events Rooted in Chromospheric Activity
- Coronal hole boundaries at small scales: IV. SOT view Magnetic field properties of small-scale transient brightenings in coronal holes
- Synchronic coronal hole mapping using multi-instrument EUV images: Data preparation and detection method
- Automated Coronal Hole Identification via Multi-Thermal Intensity Segmentation
- Simulations of small-scale explosive events on the Sun
- Characteristics of Low-Latitude Coronal Holes near the Maximum of Solar cycle 24
- Flows and Motions in Moss in the Core of a Flaring Active Region: Evidence for Steady Heating
- Coronal hole boundaries at small scales: III. EIS and SUMER views
- 3-Phase Evolution of a Coronal Hole, Part I: 360° remote sensing and in-situ observations
- The quiet Sun average Doppler shift of coronal lines up to 2 MK
- Hot Plasma in Non-Flaring Active Regions Observed by the Extreme-ultraviolet Imaging Spectrometer on Hinode
- Statistical study of network jets observed in the solar transition region: A comparison between coronal holes and quiet sun regions
- Coronal hole boundaries evolution at small scales: I. EIT 195 A and TRACE 171 A view
- Investigating the Transition Region Explosive Events and Their Relationship to Network Jets
- Rotating Network Jets in the quiet Sun as Observed by IRIS
- Diagnostics of the Coronal Hole and the adjacent Quiet Sun by The Hinode/EUV Imaging Spectrometer (EIS)
- Quiet-Sun and Coronal Hole in \ion{Mg}{2}~k line as observed by IRIS
- Principle of Minimum Energy in Magnetic Reconnection in a Self-Organized Critical Model for Solar Flares
- On the formation of solar wind & switchbacks, and quiet Sun heating
- Extraction of Active Regions and Coronal Holes from EUV Images Using the Unsupervised Segmentation Method in the Bayesian Framework
- Coronal heating and solar wind formation in quiet Sun and coronal holes: a unified scenario
- Automatic detection of small-scale EUV brightenings observed by the Solar Orbiter/EUI
- Origin of Quasi-Periodic Pulsation at the Base of Kink Unstable Jet
- Diagnostic of Homologous Solar Surge Plasma as observed by IRIS and SDO
- The Center-to-Limb Variation of Non-Thermal Velocities using IRIS Si IV
- Center to limb variation of transition region Doppler shift in active regions