Brett A. McGuire

Ph.D. Physical Chemistry 2014
California Institute of Technology

M.S. Physical Chemistry 2011
Emory University

B.S. Chemistry 2009
University of Illinois at Urbana-Champaign

Research Interests

NASA missions have found some of the most chemically diverse organic materials ever detected in astronomical environments yet there is no agreed upon chemical pathway as to their formation. We know from meteorites and, more recently, cometary samples returned by the STARDUST mission that amino acids, the building blocks of life as we understand it, are present in extraterrestrial sources (Elsila et al. 2009). In the last decade, complex gas-grain chemical models have become widely used tools in the attempt to understand the chemical pathways that can result in the species observed and their abundances in interstellar environments. A key goal of these models is to attempt to predict the most likely chemical pathways for the formation of life-essential molecules, such as amino acids. While such methods are valuable, they suffer both from a lack of laboratory data and a lack of observational data with which to constrain them. Thus, laboratory studies and observational follow-ups are vital.

In the laboratory, I have recently constructed a spectrometer to measure the far-infrared (THz) absorption spectra of interstellar ice analogs. Such ices may be the dominant source of complex molecule formation in the ISM, and yet their compositions are largely unknown due to the difficulty of characterizing them using known infrared spectra. The THz region of the spectrum, which overlaps well with the new SOFIA observatory’s capabilities, provides the opportunity for unambiguous observation and characterization of these ices once laboratory data are known. We have recently produced the first results from this instrument by recording the THz spectra of water ice, the most abundant interstellar ice species, and are in the process of expanding to mixtures of ices which include simple species such as CO and CO2, as well as more complex species such as methanol and methyl formate.

I am also a member of a team of astronomers working to expand our knowledge of the gas-phase chemical inventories in the ISM through the Prebiotic Molecular Survey of the Sgr B2(N) star-forming region. As a result, I have published the first detection of carbodiimide (HNCNH) in space, which was observed through masing transitions, and am actively involved in the analysis of a number of other new molecular species. Through observational programs such as this, which rely heavily on complimentary laboratory efforts, I hope to shed light on the processes which can give rise to species such as glycine in the ISM.

Publications

A full list of publications and presentations can be found in my CV available here in PDF format.
  • McGuire, B.A., Carroll, P.B., Boyton, A.N., Mendez, J.M., and Blake, G.A., "The ignition of thermite using the potassium chlorate rocket reaction - a systematic demonstration of reaction chemistry," J. Chem. Ed., 2015, in press.

  • Loomis, R.A., McGuire, B.A., Shingledecker, C., Burkhardt, A., Johnson, C.H., Blair, S., Robertson, A., and Remijan, A.J., "Investigating the minimum energy principle in searches for new molecular species - the case of H2C3O isomers," Astrophys J., 2015, 799, 34.

  • Carroll, P.B., McGuire, B.A., Remijan, A.J., Apponi, A.J., Ziurys, L.M., Lovas, F.J., and Blake, G.A., "The search for a complex molecule in a selected hot core region: a rigorous attempt to confirm trans-ethyl methyl ether toward W51 e1/e2," Astrophys J., 2015, 799, 15.

  • Ioppolo, S.I., McGuire, B.A., Allodi, M.A., and Blake, G.A., "THz and mid-IR spectroscopy of interstellar ice analogs: methyl and carboxylic acid groups," Faraday Discuss., 2014, 168, 461.

  • Remijan, A.J., Snyder, L.E., McGuire, B.A., et al., "Observational results of a multi-telescope campaign in search of interstellar urea [(NH2)2CO]," Astrophys J., 2014, 783, 77.

  • McGuire, B.A., Carroll, P.B., Gratier, P., et al., "An observational investigation of the identity of B11244 ( l-C3H+/C3H- )," Astrophys J., 2014, 783, 36.

  • Allodi, M.A., Ioppolo, S.I., Kelley, M.J., McGuire, B.A., and Blake, G.A., "The structure and dynamics of carbon dioxide and water containing ices investigated via THz and mid-IR spectroscopy," Phys. Chem. Chem. Phys., 2014, 16, 3442.

  • McGuire, B.A., Carroll, P.B., Blake, G.A., Hollis, J.M., Lovas, F., Jewell, P.R., and Remijan, A.J., "A search for l-C3H+ in Sgr B2(N), Sgr B2(OH), and the Dark Cloud TMC-1," The Astrophysical Journal, 2013, 774, 56.

  • Carroll, P.B., McGuire, B.A., Zaleski, D.P., Neill, J.L., Pate, B.H., and Widicus Weaver, S.L., "The rotational spectra of glycoladehyde isotopologues measured in natural abundance by chirped-pulse Fourier transform microwave spectroscopy," Journal of Molecular Spectroscopy, 2013, 284-285, 21.

  • McGuire, B. A., Loomis, R. A., Charness, C. M., Corby J. F., Blake, G. A., Hollis, J. M., Lovas, F. J., Jewell, P. R., and Remijan, A. J., “Interstellar Carbodiimide (HNCNH) - A New Astronomical  Detection from the GBT PRIMOS Survey via Maser Emission Features," Astrophys. J. Lett., 2012 , 758, L33.

  • Pulliam, R. McGuire, B.A., and Remijan, A.J., "A search for interstellar hydroxylamine (NH2OH) toward select astronomical sources," Astrophys. J., 2012, 751, 1.

  • McGuire, B.A., Wang, Y., Bowman, J.M., and Widicus Weaver, S.L., "Do H5+ and its isotopologues have rotational spectra?" J. Phys. Chem. Lett., 2011, 2, 1405-1407.

  • Crabtree, K.N., Kauffman, C.A., Tom, B.A., Becka, E., McGuire, B.A., and McCall, B.J., "Nuclear spin dependence of the reaction of H3+ with H2 II. Experimental Measurements," J. Chem. Phys., 2011, 134, 194311.

  • Lovas, F.J., Plusquellic, D.F., Widicus Weaver, S.L., McGuire, B.A., and Blake, G.A., "Organic Compounds in the C3H6O3 famliy: microwave spectrum of cis-cis dimethyl carbonate," J. Mol. Spec., 2010, 264, 10-18.