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Douglas C. B. Whittet
Professor of Physics; Associate Director, New York Center for Studies on the Origins of Life
Education:
Ph.D., Astronomy, University of St Andrews, 1975.
M.S., Radio Astronomy, University of Manchester, 1971.
B.S., Physics (Hons.), University of St Andrews, 1970.
Career Highlights:
Since 1994 - Professor of Physics, Rensselaer Polytechnic Institute.
1991/94 - Associate Professor of Physics, Rensselaer Polytechnic Institute.
1980/90 - Senior Lecturer and Professor of Astronomy, Lancashire Polytechnic.
1978/80 - Post-doctoral Research Associate, University College, London.
1975/77 - Post-doctoral Research Associate, University of St Andrews.
Research Interests:
Our research seeks to test the hypothesis that organic molecules relevant to the origin of life are ubiquitous to interstellar condensations from which planetary systems are born. The principal carriers of the biogenic elements in interstellar clouds are submicron sized dust grains. The physical and chemical properties of these particles, and their evolution with respect to time in regions of active star formation, are important and topical issues in modern astrophysics which have potentially far-reaching implications for studies of the origin of life.
Research on star formation has been greatly stimulated in recent years by advances in infrared astronomy, providing a means of studying stellar populations deep within molecular clouds in regions hidden from view at visible wavelengths. Infrared observations also provide an extremely powerful technique for investigating the nature of interstellar dust: solid state spectral features contain a wealth of information on the composition, internal structure and thermal history of the grains. The spectral resolving power required to extract all information inherent in the profiles is now routinely available on both ground-based telescopes and the Infrared Space Observatory.
We are carrying out a systematic study of infrared dust features in a carefully selected sample of embedded young stellar objects and distant field stars viewed through molecular clouds. The primary aim is to explore the evolution of icy grain mantles in the cocoons of low-mass protostars, using the field stars as the 'control experiment' delineating dust properties in undisturbed molecular-cloud material.
Results are interpreted with reference to the optical properties of compounds synthesised in the laboratory under simulated interstellar conditions. Our observations provide detections of not only simple ices such as H2O, CO and CO2, but also organic molecules of various degrees of complexity and oxidation state, including CH4, CH3OH, H2CO, HCOOH and HCN. This program of research will lead to a clear understanding of the evolution of organic matter in dust in the environments of objects which are realistic analogs of the early Solar System.
This research is being carried out in collaboration with groups at the Spitzer Science Center, the SETI Institute, the University of Alabama at Birmingham, the University of Missouri - St Louis, Ohio State University, and the University of Hertfordshire (UK).
Selected Publications:
“Dust in the Galactic Environment” (Second edition), Whittet, D.C.B. 2003, Institute of Physics Graduate Series in Astronomy, pp.390.
“Interstellar extinction and polarization in the Taurus Dark Clouds: The optical properties of dust near the diffuse/dense cloud interface”, Whittet, D.C.B., Gerakines, P.A., Hough, J.H., & Shenoy, S.S. 2001, Astrophys. J., 547, 872-884.
“Interstellar ices as a source of CN-bearing molecules in protoplanetary disks”, Whittet, D.C.B., Gibb, E.L., & Nummelin, A. 2001, Origins of Life, 31, 157-165.
“Solid carbon dioxide in regions of low-mass star formation”, Nummelin, A., Whittet, D.C.B., Gibb, E.L., Gerakines, P.A., & Chiar, J.E. 2001, Astrophys. J., 558, 185-193.
“Searching for ammonia in grain mantles toward massive YSOs”, Gibb, E.L., Whittet, D.C.B., & Chiar, J.E. 2001, Astrophys. J., 558, 702-716.
“The 6-micron feature in protostars: Evidence for organic refractory material”, Gibb, E.L., & Whittet, D.C.B. 2002, Astrophys. J., 566, L113-L116.
“A test case for the organic refractory model of interstellar dust”, Shenoy, S.S., Whittet, D.C.B., Chiar, J.E., Adamson, A.J., Roberge, W.G., & Hassel, G.E. 2003, Astrophys. J., 591, 962-967.
“The role of polycyclic aromatic hydrocarbons in ultraviolet extinction: Probing small molecular PAHs”, Clayton, G.C., Gordon, K.D., Salama, F., Allamandola, L.J., Martin, P.G., Snow, T.P., Whittet, D.C.B., Witt, A.N., & Wolff, M.J. 2003, Astrophys. J., 592, 947-952.
“Interstellar ice: The ISO legacy”, Gibb, E.L., Whittet, D.C.B., Boogert, A.C.A. & Tielens, A.G.G.M. 2004, Astrophys. J. Supp., 151, 35-73.
“The ultraviolet extinction curve of intraclump dust in Taurus (TMC-1): Constraints on the 2175A bump absorber”, Whittet, D.C.B., Shenoy, S.S., Clayton, G.C., & Gordon, K.D. 2004, Astrophys. J., 602, 291-297.
Contact:
(518) 276-8413
whittd@rpi.edu
Home Page: http://www.rpi.edu/~whittd/
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