The physical structure of the planetary nebula NGC 6781
نویسندگان
چکیده
منابع مشابه
The physical structure of the point - symmetric and quadrupolar planetary nebula NGC 6309
Aims. We analyse the point-symmetric planetary nebula NGC 6309 in terms of its three-dimensional structure and of internal variations of the physical conditions to deduce the physical processes involved in its formation. Methods. We used VLA-D λ3.6-cm continuum, ground-based, and HST-archive imaging as well as long slit highand low-dispersion spectroscopy. Results. The low-dispersion spectra in...
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Direct imagery and long-slit, spatially resolved echellograms of the high excitation planetary nebula NGC 1501 allowed us to study in detail the expansion velocity field, the physical conditions (electron temperature, electron density, ionization) and the spatial distribution of the nebular gas. An electron temperature of 11500 K and a turbulence of 18 km s−1 are derived by comparing the Hα and...
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The spectrum of the planetary nebula NGC 6302 is presented, as it was observed by the ISO short-wavelength spectrometer. The IUE spectrum observed at the same position with the same aperture is also presented.
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15 صفحه اولThe central star of the Planetary Nebula NGC 6537
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2001
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20010752