Abstract
Carbon in the Universe
Organic Circumstellar Studies with the James Webb Space Telescope
Iain McDonald
University of Manchester

At least half of all ISM dust in the Local Universe is produced by asymptotic giant branch stars (AGBs), where more than 60 molecular species have been detected in their outflows. These stars are the source of the main organic species we see in space today, including polycyclic aromatic hydrocarbons (PAHs) which are ubiquitous in the Universe, and fullerenes, the largest molecules ever identified in space by our group. The past decades have witnessed the detection of a rich and complex organic inventory produced by these carbon stars and detected in the mid-IR that includes amorphous carbon, acetylene, polyacetylenic chains, benzene, SiC, unidentified 21um and 20um bands and plateau at 6-9 and 10-13um, PAHs, and fullerenes. Despite its importance, we do not yet understand the formation nor the evolutionary link between the major carbonaceous species. With its capabilities, the James Webb Space Telescope (JWST) is ideally placed to revolutionise our understanding of organic chemistry. It will allow us to spatially resolve and locate the emission of many species in Galactic sources providing key insights in their formation, push the detection limit of AGBs, post-AGBs and planetary nebulae in the IR beyond the Milky Way and Magellanic Clouds, and will enable us to spectrally resolve the complex chemistry present in the elusive phase where PAHs form. In this presentation I will review our current knowledge of carbonaceous dust evolution in circumstellar media, the current challenges, and describe the opportunities that JWST will provide in this field.
Schedule
Friday
13:30 - 15:00
14:15
EX - C33 (150)

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