Abundances of Planetary Nebulae BD+30 3639 and NGC 6543

Abstract

Infrared spectra taken with the Short Wavelength Spectrometer on board ISO and UV observations with IUE of planetary nebulae BD+30 3639 and NGC 6543 are presented. The extinction derived using infrared lines for BD+30 3639 is E_B-V= 0.34, slightly higher than previous determinations. For NGC 6543 the extinction found from the hydrogen lines is E_B-V= 0.07. Infrared, optical and ultraviolet data have been used to derive the physical parameters of the nebula. BD+30 3639 has an average T_e= 8500 K and N_e= 11 000 C_{H_beta}m3. In the case of NGC 6543 a T_e = 8200 K and N_e = 5000 C_{H_beta}m3 have been found, in agreement with previous determinations. The element abundances have been derived and compared to those found in the Sun and O, B stars. This comparison gives a hint of the mass of the progenitor stars from which they evolved.

Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, The Netherlands and the United Kingdom) and with the participation of ISAS and NASA.