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Start Over Creator Schmieder, B.

1. A study of activity in interacting sunspot groups

Creator:
Schmieder, B., van Driel-Gesztelyi, L., and Hénoux, J.-C.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
heliophysics and sunspot groups
Language:
Czech
Description:
Two interacting active regions of different ages have been studied over two days using white light and Hα observations as well as magnetograma. Different series of homologous flares and the formation of a filament in tbe region were analysed and an interpretation of these events is proposed.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

2. Microflares and active filaments

Creator:
Schmieder, B., Fontenla, J., and Tandberg-Hanssen, E.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
heliophysics, microflares, and filaments
Language:
Czech
Description:
Using some observational evidences of filament disturbances associated with microflares we point out the following results: 1. The filament destabilization begins at one of its footpoint, 2. Glose to this footpoint one of two pores are observed, they move with an anomalous velocity as seen in white light pictures. 3. Bríghtenings in Hα and in C IV overlie the location of the pores. The pores may be the signature of new emerging flux. 4. The dynamics observed in Hα filament is generally associated with heating of the filament transitíon zone. 5. The excess energy is released at different places along the filament, but this process does not seem to imply a heating conduction front.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

3. On the onset of eruptive prominences and coronal transients

Creator:
Simon, G., Mein, N., Schmieder, B., Tandberg-Hanssen, E., and Wu, S. T.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
observations, eruptive prominences, and coronal transients
Language:
Czech
Description:
During the Maximum Year, preflare and preeruptive phenomena have been observed which give a new idea on the association of eruptive prominences and coronal transients. The propagation of a C IV brightening through a prominence is related to the onset of a MHD wave. It is followed by the activation of the prominence and its eruption some two hours later. A coronal transient is observed above 1.6 Rs. It is argued that the eruption of the prominence is the result of perturbations in the magnetic field configuration initiated by the MHD waves. The consequence would be that more generally the primary initiation of the eruption may happen up to several hours before the rlse of the prominence.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

4. Surges as tracers of magnetic lines

Creator:
Schmieder, B., Hein, P., Martres, M. J., Simmet, G., and Tandberg-Hanssen, E.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
solar atmosphere, surges, and magnetic lines
Language:
Czech
Description:
During the maximum activity year 1980, chromospheric mass ejections were observed with the Multichannel Subtractive Double Pass Spectrograph operating at Mcudon (MSDP), while the UV and X ray emissions were observed respectively with Ultra Violet Spectrograph (UVSP) and HXIS instruments on board the SMM satellite. These ejections are not related directly to flares but are located in active regions near sunspots. As the magnetic field is frozen in the matter, the study of the velocity field leads to the geometry of the magnetic structures and to the temporal evolution of the magnetic field lines. Ejections of matter recur often with a period of 10 to 20 minutes. In CIV, the bright loops colncide with the Hα surge but are more extended. Associated with the events are either X ray emission or type III bursts. We interprete these signatures by invoking, respectively closed or open structures. The estimate of the energy involved gives constraints on the mechanism responsible for the surge.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

5. The evershed flow in the solar photosphere, chromosphere and chromosphere-corona transition region

Creator:
Alissandrakis, C. E., Dialetis, D., Mein, P., Schmieder, B., and Simon, G.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
astrophysics, sunspot regions, and evershed flow
Language:
Czech
Description:
We have studied the height dependent characteristics of the Evershed flow in the photosphere, chromosphere and chromosphere-corona transition region. We have used the Multichannel Subtractive Double Pass Spectrograph (MSDP) to obtain line of sight velocity maps in Hα, the Meudon magnetograph for mapping the photospheric velocity field and the Ultraviolet Spectrometer and Polarimeter (UVSP) on the Solar Maximum Mission (SMM) spacecraft to obtain line of sight velocities in C IV, in sunspot regions. Our emphasis was on the large scale, quasi-stationary characteristics of the flow. In the photosphere the velocity is low above the umbra and shows a maximum above the penumbra. In addition to the reversal of the flow in the chromosphere both the characteristic scale of the flow and the velocity are larger; the velocity maximum is located outside the photospheric penumbra. In the chromosphere-corona transition region there is a clear tendency for a chromospheric-type Evershed effect with a predominantly horizontal flow. The velocity is greater than in the chromosphere, but the characteristic scale of the flow is about the same. In addition to the Evershed flow, C IV observations show upflows above the umbra with a velocity of about 15 km/sec.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public