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A Rigorous Attempt to Verify Interstellar Glycine



Lewis E. Snyder, Francis J. Lovas, J M. Hollis, Douglas N. Friedel, P R. Jewell, A Remijan, Vadim V. Ilyushin, E A. Alekseev, S K. Dyubko


In 2003, Kuan, Charnley, and co-workers claimed the detection of interstellar glycine (NH2 CH2COOH) based on the detection of 27 lines in 19 different spectral bands in one or more of the sources Sgr B2(N-LMH), Orion KL, and W51 e1/e2. They supported their detection claim with rotational temperature diagrams for all three sources. In this paper, we use new laboratory measurements of glycine and other molecules as a basis to argue that key lines necessary to an interstellar glycine detection have been misassigned. We illustrate that rotational temperature diagrams used without the support of correct spectroscopic assignments are not a reliable tool for the identification of interstellar molecules. Our investigation conclusively demonstrates that the case for the detection of interstellar glycine has yet to be made.
Astrophysical Journal
No 2


abundances, glycine, interstellar clouds, interstellar molecules, radio astronomy, rotational transitions


Snyder, L. , Lovas, F. , Hollis, J. , Friedel, D. , Jewell, P. , Remijan, A. , Ilyushin, V. , Alekseev, E. and Dyubko, S. (2005), A Rigorous Attempt to Verify Interstellar Glycine, Astrophysical Journal (Accessed June 23, 2024)


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Created January 31, 2005, Updated October 12, 2021