Spectrophotometry of the planetary nebula KjPn 8 |
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| Authors: | R Vázquez R L Kingsburgh & J A López |
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| Institution: | Instituto de Astrofísica de Andalucía, CSIC, Apdo. Postal 3004, 18080 Granada, Spain,;Instituto de Astronomía, UNAM, Apdo. Postal 877, 22800 Ensenada, B. C., Mexico,;Department of Physics and Astronomy, York University, 4700 Keele Street, North York, Ontario, Canada M3J1P3 |
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| Abstract: | Flux-calibrated low-resolution spectra covering the optical wavelength range from 3400 to 7500 ? have been obtained over the central region and the surroundings of the extraordinary planetary nebula (PN) KjPn 8 (PNG 112.5-00.1). The spectrum from the core is of low excitation with T e(N II ) = 8000 K and n e(S II ) = 550 cm?3. KjPn 8 is found to be a Type I PN according to the original classification scheme of Peimbert & Torres-Peimbert, with enriched He/H and N/O ratios with respect to mean values for PN. Increased O/H, Ne/H and Ar/H ratios over those of average PN reflect the possible metal-rich environment from which the progenitor star formed, and also are similar to those found in the extreme Type I PN He 2-111. The N/H ratio is found to be only moderately high compared to the average PN and consequently, the large O abundance pulls the N/O ratio towards the lower limit of the criterion for Type I planetary nebulae (PNe) in this case. In addition, the spectra of some knots and faint regions in the KjPn 8 surroundings are presented, which show only a few spectral lines. Low electron densities ranging from 100 to 300 cm?3 have been derived in these outer regions. |
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| Keywords: | ISM: abundances planetary nebulae: individual: KjPn 8 |
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