Search Publications
Resonant Absorption of Transverse Oscillations and Associated Heating in a Solar Prominence. II. Numerical Aspects
De Pontieu, B.; Yokoyama, T.; Okamoto, T. J. +3 more
Transverse magnetohydrodynamic (MHD) waves are ubiquitous in the solar atmosphere and may be responsible for generating the Sun’s million-degree outer atmosphere. However, direct evidence of the dissipation process and heating from these waves remains elusive. Through advanced numerical simulations combined with appropriate forward modeling of a p…
Temporal Evolution of Chromospheric Evaporation: Case Studies of the M1.1 Flare on 2014 September 6 and X1.6 Flare on 2014 September 10
Reeves, Katharine K.; Chen, Bin; Liu, Wei +3 more
With observations from the Interface Region Imaging Spectrograph, we track the complete evolution of ∼11 MK evaporation flows in an M1.1 flare on 2014 September 6 and an X1.6 flare on 2014 September 10. These hot flows, as indicated by the blueshifted Fe xxi 1354.08 Å line, evolve smoothly with a velocity decreasing exponentially from ∼200 km s
The Multithermal and Multi-stranded Nature of Coronal Rain
Rouppe van der Voort, L.; Pereira, T. M. D.; Scullion, E. +2 more
We analyze coordinated observations of coronal rain in loops, spanning chromospheric, transition region (TR), and coronal temperatures with sub-arcsecond spatial resolution. Coronal rain is found to be a highly multithermal phenomenon with a high degree of co-spatiality in the multi-wavelength emission. EUV darkening and quasi-periodic intensity v…
Homologous Helical Jets: Observations By IRIS, SDO, and Hinode and Magnetic Modeling With Data-Driven Simulations
Golub, L.; Tian, H.; Cheung, Mark C. M. +18 more
We report on observations of recurrent jets by instruments on board the Interface Region Imaging Spectrograph, Solar Dynamics Observatory (SDO), and Hinode spacecraft. Over a 4 hr period on 2013 July 21, recurrent coronal jets were observed to emanate from NOAA Active Region 11793. Far-ultraviolet spectra probing plasma at transition region temper…
The Relation between Solar Eruption Topologies and Observed Flare Features. I. Flare Ribbons
Pariat, E.; DeLuca, E. E.; McKillop, S. +5 more
In this paper we present a topological magnetic field investigation of seven two-ribbon flares in sigmoidal active regions observed with Hinode, STEREO, and Solar Dynamics Observatory. We first derive the 3D coronal magnetic field structure of all regions using marginally unstable 3D coronal magnetic field models created with the flux rope inserti…
Resonant Absorption of Transverse Oscillations and Associated Heating in a Solar Prominence. I. Observational Aspects
Van Doorsselaere, Tom; Antolin, Patrick; De Pontieu, Bart +3 more
Transverse magnetohydrodynamic waves have been shown to be ubiquitous in the solar atmosphere and can, in principle, carry sufficient energy to generate and maintain the Sun’s million-degree outer atmosphere or corona. However, direct evidence of the dissipation process of these waves and subsequent heating has not yet been directly observed. Here…
The Influence of Spatial resolution on Nonlinear Force-free Modeling
Sun, X.; Schrijver, C. J.; Canou, A. +11 more
The nonlinear force-free field (NLFFF) model is often used to describe the solar coronal magnetic field, however a series of earlier studies revealed difficulties in the numerical solution of the model in application to photospheric boundary data. We investigate the sensitivity of the modeling to the spatial resolution of the boundary data, by app…
How Common Are Hot Magnetic Flux Ropes in the Low Solar Corona? A Statistical Study of EUV Observations
Patsourakos, S.; Nindos, A.; Vourlidas, A. +1 more
We use data at 131, 171, and 304 Å from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory to search for hot flux ropes in 141 M-class and X-class solar flares that occurred at solar longitudes equal to or larger than 50°. Half of the flares were associated with coronal mass ejections. The goal of our survey is to assess the …
Evidence of Thermal Conduction Suppression in a Solar Flaring Loop by Coronal Seismology of Slow-mode Waves
Sun, Xudong; Ofman, Leon; Davila, Joseph M. +2 more
Analysis of a longitudinal wave event observed by the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory is presented. A time sequence of 131 Å images reveals that a C-class flare occurred at one footpoint of a large loop and triggered an intensity disturbance (enhancement) propagating along it. The spatial features and temp…
On the 2012 October 23 Circular Ribbon Flare: Emission Features and Magnetic Topology
Ding, M. D.; Yang, Kai; Guo, Yang
Circular ribbon flares are usually related to spine-fan type magnetic topology containing null points. In this paper, we investigate an X-class circular ribbon flare on 2012 October 23, using the multiwavelength data from the Solar Dynamics Observatory, Hinode, and RHESSI. In Ca ii H emission, the flare showed three ribbons with two highly elongat…