Morphology and ionization characteristics of planetary nebulae PB 1 and PC 19

We present results of our study of two planetary nebulae (PNe), PB1 and PC 19. We use the optical spectra of these two PNe observed at 2 m Himalayan Chandra Telescope and also archival and literature data for the study. We use the morphokinematic code SHAPE to construct 3D morphologies of the PNe and the photoionization code CLOUDY to model the observed spectra. The 3D model of PB 1 consists of an elongated shell surrounded by a bipolar halo and that of PC 19 consists of an open lobed bipolar structure and a spiral filamentary pair. We analyse the ionization structure of the PNe by deriving several plasma parameters and by photoionization modelling. We estimate the elemental abundances of the elements, He, C, N, O, Ne, S, Ar, and Cl, from our analysis. We find He, C, and N abundances to be significantly higher in case of PB 1. We estimate different physical parameters of the central stars, namely effective temperature, luminosity, and gravity, and of the nebula, namely hydrogen density profiles, radii, etc., from photoionization modelling. We estimate distances to the PNe as similar to 4.3 kpc for PB 1 and as similar to 5.6 kpc for PC 19 by fitting the photoionization models to absolute observed fluxes. Progenitor masses are estimated from theoretical evolutionary trajectories and are found to be similar to 1.67 and similar to 2.38 M-circle dot for PB 1 and PC 19, respectively.