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Appendix A: New emission-line central stars

A considerable fraction of the Galactic PNe population has emission-line central stars of different types (Weidmann & Gamen 2011). We used our new TNG/DOLORES observations to look for their presence in our sample. We found five objects (Bl 2-1, He 2-440, IC 4846, K 3-56, and K 4-41) to be possible Wels-type objects (see Tylenda et al. 1993). Only one object (K 3-15) could tentatively be classified as a Wolf–Rayet type [WC 11] central star. Taking the very low-ionization state of this nebula into account we instead classified it as a VL-type object – a member of a class of emission-line stars recently introduced by Górny et al. (2009). The full optical spectrum of K 3-15 (low-ionization nebula) and also of K 3-56 (high-ionization nebula) have been presented in Fig. 1. In Fig. A.1 we present details of the spectra of all new emission-line central star candidates in our observed sample. In this plot the expected locations of the characteristic stellar emission lines are indicated with dotted lines, and if positively identified they are then marked with the name of the appropriate ion.

	Fig. A.1 Spectra of the new PNe with emission-line central stars. Expected locations of characteristic features are indicated by dotted lines and labelled with the appropriate ion name if present in the spectra.
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Appendix B: Spectra of the three suspected symbiotic stars

The full optical spectra of the three suspected symbiotic stars (CTSS 2, K 4-57, and Th 4-1) are displayed in Fig. B.1. Their Spitzer IR spectra (with the unusual presence of hot dust emission) are very different from the other Galactic PNe studied here, and their optical spectra are suggestive of a possibly symbiotic classification. For example, the 2MASS colours of PN K 4-57 are consistent with a D-type symbiotic PN. A detailed analysis of this small group of symbiotic stars will be presented elsewhere.

	Fig. B.1 Spectra of the three suspected symbiotic stars.
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© ESO, 2014