Iron Depletion into Dust Grains in Galactic Planetary Nebulae

TL;DR

This study investigates iron depletion into dust grains in 20 Galactic planetary nebulae, revealing high depletion levels with over 80% of iron condensed into dust, and explores potential links to nebula morphology.

Contribution

It provides the first comparative analysis of iron depletion in Galactic bulge and disk planetary nebulae, highlighting high depletion levels across different environments.

Findings

Over 80% of iron is condensed into dust in all studied nebulae.

Iron depletion varies over two orders of magnitude among the sample.

No significant correlation between iron depletion and nebula morphology.

Abstract

We present preliminary results of an analysis of the iron depletion factor into dust grains for a sample of 20 planetary nebulae (PNe) from the Galactic bulge. We compare these results with the ones we obtained in a prior analysis of 28 Galactic disk PNe and 8 Galactic H II regions. We derive high depletion factors in all the objects, suggesting that more than 80% of their iron atoms are condensed into dust grains. The range of iron depletions in the sample PNe covers about two orders of magnitude, and we explore here if the differences are related to the PN morphology. However, we do not find any significant correlation.