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| EPoS Contribution |
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The search of pre-biotic molecules in young Solar-type systems
Izaskun Jimenez-Serra ESO, Garching, DE | |
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Glycine (NH2CH2COOH) is the simplest aminoacid and a key constituent of living organisms. Its detection in the interstellar medium (ISM) is therefore of great importance to understand the formation mechanisms of very large complex organic molecules, and in particular of pre-biotic species, in the ISM. For over a decade, glycine has extensively been searched for toward high-mass hot molecular cores. These studies, however, have not yielded any detection. Several challenges are faced in the search of glycine in high-mass star forming regions. Hot cores are chemically very active and their observed molecular line spectra present a high level of line confusion. In addition, the typical linewidths of the molecular line emission in hot cores are of some km/s, which leads to line blending and prevents the clear identification of weak lines from low-abundance molecular species such as glycine.
In contrast to high-mass star forming regions, their low-mass counterparts (specially the earliest stages represented by pre-stellar cores) may be better suited for the detection of glycine since their gas temperatures are low (<10 K) and the typical linewidths of their line emission are very narrow (<0.5 km/s). Encouraged by the recent detection of water vapour and of complex organic molecules in pre-stellar cores, we have carried out simple excitation and radiative transfer calculations of the glycine line emission expected from the low-mass pre-stellar core L1544. Assuming that glycine is photo-evaporated from grain mantles in the same way as water does in L1544, and considering that the glycine abundance on dust grains is ~0.01 percent that of water, our calculations predict peak intensities larger than >10 mK for several rotational lines of glycine between 65 GHz and 130 GHz. These results open up the possibility to detect glycine and other pre-biotic molecules at the earliest stages in the formation of proto-Solar systems, allowing the connection between the pre-biotic chemistry in the ISM and their subsequent delivery into protoplanetary systems. | |
| Collaborators: L. Testi, ESO, Germany P. Caselli, ULeeds, UK S. Viti, UCL, UK |
Suggested Session:
Chemistry |