Time series of white-light pictures of the sunspot NOAA 7522, obtained at the Swedish Vacuum Solar Telescope (La Palma), were analyzed to study the proper...
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PublicaciónOn the Dynamics of Bright Features in Sunspot Umbrae
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PublicaciónOn the Energy Balance of Solar Active Regions
Ground-based observations of the sunspot irradiance deficit Ψ and the excess by facular regions in the period 1989 June 3-15 are analyzed using photometric...
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PublicaciónOn the fine structure of sunspot penumbrae. I. A quantitative comparison of two semiempirical models with implications for the Evershed effect
Sunspot penumbrae exhibit prominent fine structure. Different interpretations of spectropolarimetric observations suggest different, sometimes contradictory...
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PublicaciónOn the fine structure of sunspot penumbrae. II. The nature of the Evershed flow
We investigate the fine structure of the sunspot penumbra by means of a model that allows for a flux tube in horizontal pressure balance with the magnetic...
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PublicaciónOn the fine structure of sunspot penumbrae. III. The vertical extension of penumbral filaments
In this paper we study the fine structure of the penumbra as inferred from the uncombed model (flux tube embedded in a magnetic surrounding) when applied to...
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PublicaciónOn the initial orientation of emerging active regions
The initial orientation of 74 active regions (ARs) as measured in high resolution pictures. As previous works by the author (Garcia de la Rosa, 1984) suggest a...
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PublicaciónOn the Moat-Penumbra Relation
Proper motions in a sunspot group with a δ-configuration and close to the solar disk center have been studied by employing local correlation tracking techniques...
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PublicaciónOn the origin of reverse polarity patches found by Hinode in sunspot penumbrae
Context: The topology of penumbral magnetic fields is poorly known. The satellite Hinode has recently revealed penumbral structures of a magnetic polarity that...
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PublicaciónOn the relation between the intensities of bright features and the local background in sunspot umbrae
A photometric study of umbral bright features (umbral dots, clusters of umbral dots, bright grains of light bridges) in sunspots is presented. It is based on...