Photo-ionization structures of Planetary Nebula IC 2003 with [WR] central star

Abstract

We present ionization structures of IC 2003, a planetary nebula with [WR] central star, using a 1-D dusty photo-ionization code: ”CLOUDY 17.03”. The photo-ionization model is constrained by archival UV emission line fluxes, medium-resolution optical spectroscopy, IRAS25μm flux, absolute Hβ flux, and the mean angular size of the nearly spherical optical nebula. To constrain the carbon abundance and the effect of photo-electric heating in the ionized gas, we used UV emission lines. We considered an amorphous carbon dust grain with MRN and KMH size distributions to address the importance of photo-electric heating in the ionized nebula. We show that KMH grain size distribution with quantum dust heating reproduces the observations quite well. We construct the ionization structures of different elements at their different ionization stages in the nebula. We derive the physical properties of the planetary nebula and its chemical composition, as well as the parameters of its central star. The estimated nebular dust-to-gas mass ratio is 2.37×10-3, and the enhanced photo-electric heating yielded by small dust grains is 9.4% of the total heating. We considered the H-poor model atmosphere for the central star; the effective temperature of the central star is 177 kK, the specific gravity log(g) is 6, and its luminosity (L∗) is 6425 L⊙. The derived central star parameters plotted on stellar evolutionary tracks correspond to a central star mass of 0.636 M⊙ and to a progenitor mass of 3.26 M⊙.