A deep survey of heavy element lines in planetary nebulae -- II. Recombination line abundances and evidence for ultra-cold plasma

Y. G. Tsamis, M. J. Barlow, X. -W. Liu +2

[Abridged] Deep optical observations of the spectra of 12 Galactic planetary nebulae (PNe) and 3 Magellanic Cloud PNe were presented in Paper I by Tsamis et al. (2003b), who carrie…