W. J. Maciel -
Abstract #57
ABUNDANCES AND RADIAL GRADIENTS FROM DISK PLANETARY NEBULAE: He, N, C, AND Cl
W. J. Maciel, C. Chiappini
Astrophys. Space Sci. 219, 231-247 (1994) Chemical abundances of the elements He, N, C, and Cl are presented for disk planetary nebulae, comprising Peimbert types I, II, and III. Average abundances for these classes are determined and compared with the remaining abundances available. The presence of abundance gradients relative to hydrogen for disk nebulae is investigated in a region of about 8 kpc centered in the solar system. It can be concluded that the gradients of the ratios N/H, Cl/H, and probably C/H are similar to the O/H gradient, especially for type II objects.
