Automated Spatiotemporal Analysis of Fibrils and Coronal Rain using the Rolling Hough Transform

Abstract

A technique is presented that automates the direction characterization of curvilinear features in multidimensional solar imaging data sets. It is an extension of the Rolling Hough Transform (RHT) technique presented by Clark, Peek, and Putman (Astrophys. J. 789, 82, 2014), and it excels at rapid quantification of spatial and spatiotemporal feature orientation even for low signal to noise applications. It operates on a pixel-by-pixel basis within a data set and reliably quantifies orientation even for locations not centered on a feature ridge, which is used here to derive a quasi-continuous map of the chromospheric fine structure projection angle. For time-series analysis, a procedure is developed that uses a hierarchical application of the RHT to automatically derive apparent motion of coronal rain observed off-limb. Essential to the success of this technique is this paper's formulation for the RHT error analysis as it provides a means to properly filter results.

This the preprint version submitted to Solar Physics. See published article for Version of Record

References in corpus (6)

• Advanced Forward Modeling and Inversion of Stokes Profiles Resulting from the Joint Action of the Hanle and Zeeman Effects
• On fibrils and field lines: The nature of H$\alpha$ fibrils in the solar chromosphere
• Can We Improve the Preprocessing of Photospheric Vector Magnetograms by the Inclusion of Chromospheric Observations?
• Inference of the chromospheric magnetic field orientation in the Ca II 8542 A line fibrils
• Segmentation of Loops from Coronal EUV Images
• Magnetic Jam in the Corona of the Sun

Cited by in corpus (14)

• Mapping the Magnetic Interstellar Medium in Three Dimensions Over the Full Sky with Neutral Hydrogen
• Coronal Magnetic Field Topology From Total Solar Eclipse Observations
• Multi-scale observations of thermal non-equilibrium cycles in coronal loops
• Spatial and Temporal Analysis of Quiescent Coronal Rain over an Active Region
• Prevalence of Thermal Non-Equilibrium over an Active Region
• Neutral Helium Triplet Spectroscopy of Quiescent Coronal Rain with Sensitivity Estimates for Spectropolarimetric Magnetic Field Diagnostics
• EUV fine structure and variability associated with coronal rain revealed by Solar Orbiter/EUI HRIEUV and SPICE
• Tracing Halpha Fibrils through Bayesian Deep Learning
• From Chromospheric Evaporation to Coronal Rain: An Investigation of the Mass and Energy Cycle of a Flare
• Total Solar Eclipse White Light Images as a Benchmark for PFSS Coronal Magnetic Field Models: An In-Depth Analysis over a Solar Cycle
• Revisiting the formation mechanism for coronal rain from previous studies
• Automated Detection Methods for Solar Activities and an Application for Statistic Analysis of Solar Filament
• A new view of the solar interface region from the Interface Region Imaging Spectrograph (IRIS)
• Structure and dynamics of erupting solar prominences using the Rolling Hough Transform: Toward a feature-oriented classification