Bibcode
Perinotto, M.; Bencini, C. G.; Pasquali, A.; Manchado, A.; Rodriguez Espinosa, J. M.; Stanga, R.
Bibliographical reference
Astronomy and Astrophysics, v.347, p.967-974 (1999)
Advertised on:
7
1999
Journal
Citations
29
Refereed citations
27
Description
We have observed the high excitation planetary nebulae NGC 7027, NGC
6543 and the low excitation planetaries Hu 2-1 and Cn 3-1 in the optical
& near IR with the aim to contribute accurate measurements of their
gaseous iron abundances. Use was made of multi-level atomic models of
iron ions to interpret the observed forbidden lines of various iron
ions. The resulting total abundances are: N(Fe)/N(H)=(4+/-2)*E(-7) ,
(3+/-2)*E(-6) , (9+/-4)*E(-7) , (6+/-3)*E(-7) , in NGC 7027, NGC 6543,
Hu 2-1, Cn 3-1, respectively. They are believed to be more accurate than
previous determinations for NGC 7027 & NGC 6543 (no previous data
were available for the other two PNe). The corresponding depletion
factors are 80, 11, 36 and 53, respectively. We don't see in this
limited sample of PNe any indication that the depletion factors are
linked with properties like the excitation of the nebula or its age.