Nonthermal Spectral Line Broadening and the Nanoflare Model

• DOI: 10.1086/505517
• Publication Date: 2006-08-15T17:59:17Z
• Authors: S. Patsourakos; J. A. Klimchuk
• Keywords: Line (geometry); Extreme ultraviolet; Solar flare; Imaging spectrometer; Corona (planetary geology); Ultraviolet; Coronal loop

A number of theoretical and observational considerations suggest that coronal loops are bundles unresolved, impulsively heated strands. This "nanoflare" model, as it is sometimes called, predicts high-speed evaporative upflows, which might be revealed nonthermal broadening spectral line profiles. We have therefore generated synthetic profile observations based on one-dimensional hydrodynamic simulations for comparison with actual observations. The predicted profiles Ne VIII (770.4 Å), a transition region line, Mg X (624.9 warm modest agrees well existing Fe XVII (254.87 hot will observed by the Extreme Ultraviolet Imaging Spectrometer (EIS) Solar-B mission, somewhat broader also consistent limited currently available. Moreover, depending properties assumed nanoflare other parameters simulation, can distinctive enhancements in wing. indicates powerful diagnostic capability exploited once launched.