Spectroscopic observations of evolving flare ribbon substructure suggesting origin in current sheet waves

Autor:	Brannon, S. R., Longcope, D. W., Qiu, J.
Rok vydání:	2015
Předmět:	Astrophysics - Solar and Stellar Astrophysics
Druh dokumentu:	Working Paper
DOI:	10.1088/0004-637X/810/1/4
Popis:	We present imaging and spectroscopic observations from the Interface Region Imaging Spectrograph (IRIS) of the evolution of the flare ribbon in the SOL2014-04-18T13:03 M-class flare event, at high spatial resolution and time cadence. These observations reveal small-scale substructure within the ribbon, which manifests as coherent quasi-periodic oscillations in both position and Doppler velocities. We consider various alternative explanations for these oscillations, including modulation of chromospheric evaporation flows. Among these we find the best support for some form of wave localized to the coronal current sheet, such as a tearing mode or Kelvin-Helmholtz instability. Comment: Accepted to Ap. J. - 34 pages, 12 figures
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1507.01554 Zobrazit plný text záznamu View this record from Arxiv