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Start Over Subject heliophysics

11. Forecast of the maximum of the next 11-year cycle of sunspots No. 23

Creator:
Kopecký, Miloslav
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
heliophysics, sunspots, and forecasts
Language:
Czech
Description:
Based on the dependence of the maximum relative RM-number of the add 11-year cycle on the RM of the previous even cycle it is forecast that RM should exceed 200 in the next 11-year sunspot cycle No. 23. and Published in Bull. Astron. Inst. Czechosl. 42 (1991), 157-158
Rights:
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12. High flare activity and redistribution of solar global magnetic fields

Creator:
Bumba, V., Hejna, L., and Gesztelyi, L.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
heliophysics, solar global magnetic fields, and flares
Language:
Czech
Description:
We demonstrate that both in the global scale and in the scale of large and complex active regions the high flare activity is dosely related to the changes in the whole background magnetic field distribution. We found that the disturbances of the normal course of MALs during the years 1965 -1980 correlated with the maxima of flare activity and the mode of MALs distribution with the mean level of solar flare numbers. We showed that the development of activity during the last two ^submaxima of the 21st cycle of solar activity, especially the formation of the white-light flare region of April 1984, were parts of global processes in the solar atmosphere. They were accompanied by a complete reorganization of the MALs patterns, background field sector structure and restructuralization of coronal holes. In both cases, in the global and in the local scales, we could follow the geophysical consequences of the entire reconstruction of global solar field amplified by the direct influence of many large flares.
Rights:
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14. Intensity profiles in fluxtubes

Creator:
Sánchez Almeida, J., Solanki, S. M., Collados, M., and del Toro Iniesta, J. C.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
heliophysics, magneticcomponents, and flux tubes
Language:
Czech
Description:
Here we presant a method for reconstructing the intensity profile, I, formed in tho magnetic elements which have diameters smaller than the best presently achlevable spatial resolutlon. It follows the same line as In Solankl and Stenflo (1984). As a starting point we use I and V (fourth Stokes parameter, whIch originates oniy In magnetic reglons) of the facula and the I observed In the quiet Sun. The filling factor, and the ratio between the continuum intensity of the magnetic and non-magnetic parts of the photosphere can be obtalned Indlrectly. For that purpose onIy the Unno equatlons, a triplet Zeeman pattern, a longitudinal magnetic field and a two-component model are needed. The method has been applied to some Fourier transform spectrometer (FTS) data (Stenflo et al., 1984) wlth promlsing results. As the absolute continuum intensities are unknown, rendering inaccurate the evaluatlon of the filling factor and the continuum contrast, oniy the normalised I profile Is obtained.
Rights:
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16. Long-period components in solar wind velocities

Creator:
Kulčár, L. and Letfus, V.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
heliophysics, solar wind velocities, and statistics
Language:
Czech
Description:
In the present contribution we applied several statistical methods of time series analysis (Fourier transform, least-squares fitting etc.) to the time series of solar wind velocity data to search for hidden periodicities. The solar wind data wo analysed were obtained on probes at the distance 1 AU from the Sun and stretched over the 17 year interval from 1963 to 1980. Because of investigating long-period components on time scales of 0.5 to 15 years in variations, we processed daily solar wind velocity values averaged over each Bartels rotation Nos. 1784 - 2006, i.e. 223 data. The analysis showed periods of 14.9-13-7, 7.2-7.1, 3.6-3.I, 2.8-2.6, 2.1- 2.0, 1.7-1.4, 1.3, 1.1, 1.0, 0.8, 0.7 and 0.6-0.5 years. Short preliminary comparison is given with periods found in various solar and geomagnetic indices.
Rights:
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17. Magnetic field gradients and X-ray emissions of solar activity centra

Creator:
Valníček, B. and Šeršeň, M.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
heliophysics and X-rays
Language:
Czech
Description:
The intensity and complexity of X-ray bursts generally is dependent by horizontal gradients of photospherical magnetic field on the line of polarity inversion. It is documented that lower gradient of H is giving (for weak X-rays) generally gradual drops of fiux, in comparison with higher one. The maxiinal value of X-radiation is proportional to the value of H-gradient on the line of polarity inversion. Generally, this gradient is determining the steepness of the front of the X-burst and of the share of hard X-rays component. This can be explained by difference in the quantity and energy of accelerated electrons in kernels of the flare.
Rights:
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19. Magnetic fields: observations and theory

Creator:
Solanki, S. K.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
heliophysics, solar active regions, and magnetic fields
Language:
Czech
Description:
Theoretical model calculations of magnetic elemcnts in the photospheric layers of solar active rcgions are cornpared with the results of observations. Emphasis is placed on small scale magnetic elements and an attempt is made to provide an overview of the contributions that the current state of theory and observation can make to answering the following questions: What is the field strength and the magnetic field structure of a magnetic element? Are magnetic elements inclined with respcct to the vertical? Do magnetic canopies exist and how can they be explained? What are the diameters of magnetic elements? What kinds of mass motions are present in magnetic flux concentrations and what role do they play for their structure and energetics? How high is the temperature in magnetic elements and what are the underlying heating mechanisms?
Rights:
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20. 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:
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