We present an analysis of the integrated Hα emission line profiles for the H SHAPE Ii region population of the spiral galaxies NGC 1530, NGC 6951 and NGC 3359. We show that ˜70% of the line profiles show two or three Gaussian components. The relations between the luminosity (log LHα) and non-thermal line width (log σnt) for the H SHAPE Ii regions

An attractive diagnostic tool for investigating the magnetism of the solar chromosphere is the observation and theoretical modeling of the Hanle and Zeeman effects in spicules, as shown in this Letter for the first time. Here we report on spectropolarimetric observations of solar chromospheric spicules in the He I λ10830 multiplet and on their

We present the optical-far-ultraviolet extinction curve of the dust in the lens galaxy of the gravitational lens system SBS 0909+532 (z=0.83). Extending our previous optical-UV estimate (from λ-10~2 to 5 μm-1) into the far ultraviolet (from λ-10~5 to 8 μm-1) is crucial for comparing with the extinction curves measured for Local Group galaxies in

We have undertaken visual spectroscopy of the highly evolved planetary nebulae (PNe) A8, A13, A62, A72, A78 and A83 over a wavelength range 4330 λ 6830Å. This permits us to specify relative line intensities in various sectors of the nebular shells, and to investigate the variation of emission as a function of radius. We determine that the

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We present observations of the quiet solar photosphere in the Fe I lines at 6302 Å where at least four different spatial locations exhibit upward-directed supersonic flows. These upflows can only be detected in the circular polarization profiles as a double-peaked structure in the blue lobe of both Fe I lines. We have detected cases of either