ar X iv : a st ro - p h / 97 05 03 0 v 1 6 M ay 1 99 7 Chemical Abundances of Planetary Nebulae in the Sagittarius Dwarf Elliptical Galaxy
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چکیده
Spectrophotometry and imaging of the two planetary nebulae He 2-436 andWray 16423, recently discovered to be in the Sagittarius dwarf elliptical galaxy, are presented. Wray 16-423 is a high excitation planetary nebula (PN) with a hot central star. In contrast He 2-436 is a high density nebula with a cooler central star and evidence of local dust, the extinction exceeding that for Wray 16-423 by EB−V = 0.28. The extinction to Wray 16-423, (EB−V =0.14) is consistent with the line of sight extinction to the Sagittarius Dwarf. Both PN show Wolf-Rayet features in their spectra, although the lines are weak in Wray 16-423. Images in [O III] and Hα+[N II], although affected by poor seeing, yield a diameter of 1.2 for Wray 16-423 after deconvolution, whilst He 2-436 was unresolved. He 2-436 has a luminosity about twice that of Wray 16-423 Based on observations at the European Southern Observatory, La Silla
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ar X iv : a st ro - p h / 97 05 03 0 v 2 1 3 M ay 1 99 7 Chemical Abundances of Planetary Nebulae in the Sagittarius Dwarf
Spectrophotometry and imaging of the two planetary nebulae He 2-436 andWray 16423, recently discovered to be in the Sagittarius dwarf elliptical galaxy, are presented. Wray 16-423 is a high excitation planetary nebula (PN) with a hot central star. In contrast He 2-436 is a high density nebula with a cooler central star and evidence of local dust, the extinction exceeding that for Wray 16-423 by...
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