Origin and location of chromospheric evaporation in flares

Journal Article · Sat Dec 31 23:00:00 EST 1983 · Adv. Space Res.; (United States)

DOI:https://doi.org/10.1016/0273-1177(84)90168-6· OSTI ID:5476960

Antonucci, E; Marocchi, D

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 to the 7th K, it is inferred 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. 13 references.

• Research Organization: Torino Universita, Turin, Italy
• OSTI ID: 5476960
• Journal Information: Adv. Space Res.; (United States), Journal Name: Adv. Space Res.; (United States) Vol. 4; ISSN ASRSD
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATMOSPHERES
CHROMOSPHERE
ELECTROMAGNETIC RADIATION
EVAPORATION
HOT PLASMA
IONIZING RADIATIONS
MEASURING INSTRUMENTS
ORIGIN
PHASE TRANSFORMATIONS
PLASMA
RADIATIONS
SOLAR ACTIVITY
SOLAR ATMOSPHERE
SOLAR FLARES
SPECTRA
SPECTROMETERS
X RADIATION
X-RAY SPECTRA