New Insights into the Dynamic Relationship between Jetlets and Plumes

Abstract:

Plumes are among the most fascinating large-scale coronal structures, but also are among the most puzzling and controversial features. They are significantly denser and have lower flow speeds than the inter-plume regions, and are rooted in regions of fine-scale, highly mixed magnetic polarity within predominantly unipolar coronal holes. The advent of high-resolution, high-cadence coronal observations from the Solar Dynamics Observatory’s Atmospheric Imaging Assembly (SDO/AIA), coupled with photospheric magnetograms from SDO’s Helioseismic and Magnetic Imager (SDO/HMI), has enabled detailed studies of plumes from their footprints outward. In particular, the detection of small transient outflows at the base of a few plumes led to the hypothesis that these “jetlets” are the long-sought source of plume mass and energy that sustain them for hours to weeks (Raouafi & Stenborg 2014). We have analyzed high-cadence multiwavelength SDO/AIA data and SDO/HMI magnetograms for a well-observed plume on 2016 July 3, focusing on the activity at the base and the fine structure within the overlying plume. In contrast to earlier studies, we used a noise-gating method (DeForest 2017) to clean the AIA and HMI data that revealed in greater detail the jetlets and other small-scale structures throughout the plume. Our investigation revealed multiple quasi-periodic jetlets within the multipolar footpoint region, throughout the period of observation, as well as evolving filamentary structures above the jetlets. This presentation will discuss the measured and derived jetlet properties, the structural and dynamic connections between the jetlets and the plume, and implications for the underlying physical processes.

DeForest C. E., Noise-gating to Clean Astrophysical Image Data, ApJ, 838, 155 (2017)

Raouafi, N. E. & G. Stenborg, Role of Transients in the Sustainability of Solar Coronal Plumes, ApJ, 787, 118 (2014)