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Bright EUV sunspot plumes have been observed in eight out of eleven different sunspot regions with the Coronal Diagnostic Spectrometer -- CDS on SOHO. From wavelength shifts we derive the line-of-sight velocity, relative to the average velocity in the rastered area, 120 arcsec x 120 arcsec. In sunspot plumes we find that the motion is directed away from the observer and increases with increasing line formation temperature, reaches a maximum between 15 and 41 km~s$^{-1}$ close to log T $approx$ 5.5, then decreases abruptly. The flow field in the corona is not well correlated with the flow in the transition region and we discuss briefly the implication of this finding.
Bright EUV sunspot plumes have been observed in five out of nine sunspot regions with the Coronal Diagnostic Spectrometer -- CDS on SOHO. In the other four regions the brightest line emissions may appear inside the sunspot but are mainly concentrated
High-quality imaging spectroscopy in the H{alpha} line, obtained with the CRisp Imaging SpectroPolarimeter (CRISP) at the Swedish 1-m Solar Telescope (SST) at La Palma and covering a small sunspot and its surroundings, are studied. They exhibit ubiqu
There have been a few reports in the literature of counter-Evershed flows observed in well developed sunspot penumbrae, i.e. flows directed towards the umbra along penumbral filaments. Here we investigate the driving forces of such counter-Evershed f
Context. The carbon monoxide (CO) molecular line at around 46655 A in solar infrared spectra is often used to investigate the dynamic behavior of the cold heart of the solar atmosphere, i.e., sunspot oscillation, especially at the sunspot umbra. Aims
Oscillations of stellar p modes, excited by turbulent convection, are investigated. We take into account the asymmetry of the up and downflows created by turbulent plumes through an adapted closure model. In a companion paper, we apply it to the form