Observations of Plasma Upflow in a Warm Loop with Hinode/EIS

Abstract

A complete understanding of Doppler shift in active region loops can help probe the basic physical mechanism involved into the heating of those loops. Here we present observations of upflows in coronal loops detected in a range of temperature temperatures (log T=5.8 - 6.2). The loop was not discernible above these temperatures. The speed of upflow was strongest at the footpoint and decreased with height. The upflow speed at the footpoint was about 20 km/s in Fe VIII which decreased with temperature being about 13 km/s in Fe X, about 8 km/s in Fe XII and about 4 km/s in FeXIII. To the best of our knowledge this is the first observation providing evidence of upflow of plasma in coronal loop structures at these temperatures. We interpret these observations as evidence of chromospheric evaporation in quasi-static coronal loops.

14 pages, 5 figures, Accepted for Publication in The Astrophysical Journal Letters

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Cited by in corpus (13)

• Persistent Doppler shift oscillations observed with HINODE/EIS in the solar corona: spectroscopic signatures of Alfvenic waves and recurring upflows
• The generation and damping of propagating MHD kink waves in the solar atmosphere
• Spectroscopic Observations of a Coronal Loop: Basic Physical Plasma Parameters Along the Full Loop Length
• IRIS Si IV Line Profiles at Flare Ribbons as Indications of Chromospheric Condensation
• Chromospheric evaporation and phase mixing of Alfvén waves in coronal loops
• Standing sausage modes in coronal loops with plasma flow
• Heating and cooling of coronal loops observed by SDO
• On Thermal-Pulse-Driven Plasma Flows in Coronal Funnels as Observed by Hinode/EUV Imaging Spectrometer (EIS)
• Model fitting of kink waves in the solar atmosphere: Gaussian damping and time-dependence
• Reconnection generated plasma flows in the quasi-separatrix layer in localised solar corona
• Direct Observations of Plasma Upflows and Condensation in a Catastrophically Cooling Solar Transition Region Loop
• Propagating Disturbances along fan-like coronal loops in an active region
• Solar Atmospheric Magnetic Energy Coupling: Broad Plasma Conditions and Spectrum Regimes