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arXiv · 1210.3750

A multi-wavelength investigation of newly discovered planetary nebulae in the Large Magellanic Cloud: Central stars

Warren A. Reid
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Abstract

Having completed my search for faint PNe in the LMC, including the outer 64 deg2 area not covered in the original UKST survey, I now have the most complete number of PNe within any galaxy with which to assess stellar parameters. I present preliminary estimates for planetary nebula central star temperatures for 688 LMC PNe using the excitation class parameter derived from emission lines in the nebula. These are then compared to a photoionisation model in order to evaluate the contribution of metallicity when determining stellar temperatures using only emission lines. I include measurements from my latest confirmatory spectroscopic observations which have yielded a further 110 new LMC PNe while confirming the 102 previously known PNe in the outer LMC. These observations, providing low and medium resolution spectra from 3650Ang to 6900Ang, have been added to my comparable data for PNe in the central 25deg2 of the LMC. The combined data were used to measure fluxes in prepa- ration for a number of projects related to luminosity functions, chemical abundances, central star properties and LMC kinematics. Here I provide a preliminary look at the range of derived central star effective temperature estimates. I also show a correlation between the central star temperatures and the expansion velocity of the nebula.

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Warren A. Reid. 2012-10-14. A multi-wavelength investigation of newly discovered planetary nebulae in the Large Magellanic Cloud: Central stars. https://arxiv.org/abs/1210.3750

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