Details

Autor(en) / Beteiligte

• Antonucci, E.
• Marocchi, D.
• Simnett, G.M.

Titel

Origin and location of chromospheric evaporation in flares

Ist Teil von

• Advances in space research, 1984, Vol.4 (7), p.111-115

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

1984

Quelle

Elsevier Journal Backfiles on ScienceDirect (DFG Nationallizenzen)

Beschreibungen/Notizen

• Observation of two flares obtained with the Solar Maximum Mission spectrometers indicate that at flare onset the emission in soft (3.5 – 8 keV) and hard (16 – 30 keV) X-rays is predominant at the footpoints of the flaring loops. Since, at the same time, blue-shifts are observed in the soft X-ray spectra from the plasma at temperature of 10 7 K, we infer that material is injected at high velocity into the coronal loops from the footpoints. These areas are also the sites of energy deposition, since their emission in hard X-rays is due to non-thermal electrons penetrating in the denser atmosphere. Hence, chromospheric evaporation occurs where energy is deposited. During the impulsive phase, the configuration of the flare region changes indicating that the flaring loop is progressively filled by hot plasma.