Physical Properties of Fullerene-containing Galactic Planetary Nebulae
Abstract
We searched the Spitzer Space Telescope data archive for Galactic planetary nebulae (PNe), that show the characteristic 17.4 and 18.9 µ m features due to C60 , also known as buckminsterfullerene. Out of 338 objects with Spitzer/IRS data, we found eleven C60 -containing PNe, six of which (Hen2-68, IC2501, K3-62, M1-6, M1-9, and SaSt2-3) are new detections. The strongest 17.4 and 18.9 µ m C60 features are seen in Tc 1 and SaSt 2-3, and these two sources also prominently show the C60 resonances at 7.0 and 8.5 µ m. In the other nine sources, the 7.0 and 8.5 µ m features due to C60 are much weaker. The flux ratio between the 17.4 and 18.9 µ m C60 feature is rather constant amongst the sample, with an average value of 0.49. We find that the Polycyclic Aromatic Hydrocarbon (PAH) profile over 6-9 µ m in these C60 -bearing carbon-rich PNe is of the more chemically-processed class A. The Spitzer spectra also show broad dust features around 11 and 30 µ m. The strength of the 11-µ m feature is correlated to the temperature of the dust, suggesting that it is at least partially due to a solid-state carrier.
- Publication:
-
Proceedings of The Life Cycle of Dust in the Universe: Observations
- Pub Date:
- 2013
- DOI:
- 10.22323/1.207.0127
- Bibcode:
- 2013lcdu.confE.127O