BIOPHYSICS SEMINAR Featuring Rob Garrod "Simulating Pre-biotic Proto-stellar Chemistry in the Age of ALMA: The Curious Case of Glycine"
Numerous complex organic molecules (COMs) are detected toward star-forming cores known as "hot cores". Aliphatic molecules of up to 12 atoms have so far been detected, including alcohols, esters, ethers and carboxylic acids. Chemical/physical simulations now suggest that many interstellar COMs are the product of UV processing of simple organic ices on the surfaces of dust grains. The formation of these molecules in protostellar envelopes may be the prelude to the development of further pre-biotic and biotic chemistry throughout the star- and planet-formation process, and the eventual incorporation into planetary bodies of molecules that are essential for the emergence of life. However, in spite of the detection of many similar molecules, the simplest amino acid, glycine, still has yet to be found toward any interstellar source.
High-sensitivity/resolution observations with the new ALMA telescope are likely to throw up many surprises in the search for new molecules. New simulations must be ready both to explain the detailed chemistry of interstellar COM formation and to take account of observed physical structure in proto-stellar sources, in order to bridge the gap between theoretical chemical abundances and observable spectral signatures.
I will present recent chemical/spectral models of complex organic chemistry in star-forming regions, with a focus on the elusive amino acid glycine. I will discuss its possible grain-surface formation; the potential for detection of glycine with ALMA; the importance of translating chemical models into full spectral simulations; and the future application of advanced pre-biotic chemistry models to new astrophysical regimes.
Rob Garrod, Center for Radiophysics & Space Research, Cornell University