2 papers
astro-ph2005
Integrated spectrum of the planetary nebula NGC 7027
Y. Zhang, X. -W. Liu, S. -G. Luo +2
We present deep optical spectra of the archetypal young planetary nebula (PN) NGC 7027, covering a wavelength range from 3310 to 9160 A. The observations were carried out by unifor…
astro-ph2004
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…