Thomas Stephan

Bio:

Research Interests:

Planetary science, Cosmochemistry, Astrophysics

Thomas has used time-of-flight secondary ion mass spectrometry (TOF-SIMS) to study mainly the chemical composition of meteorites and all kinds of available cosmic dust samples: interplanetary dust, presolar dust, and samples from the Stardust mission.

He was also involved in COSIMA (Cometary Secondary Ion Mass Analyser), a TOF-SIMS instrument onboard the European Rosetta spacecraft, that analyzed dust particles from comet 67P/Churyumov-Gerasimenko.

In a joint University of Chicago-Argonne National Laboratory project, he has developed the next generation of instruments, CHILI, based on microbeam laser resonance ionization mass spectrometry.

Recent Publications:

• Stephan T., Bloom H. E., Hoppe P., Davis A. M., Korsmeyer J. M., Regula A., Heck P. R., and Amari S. (2022) Molybdenum, ruthenium, and barium in presolar silicon carbide and graphite: s-, r-, and p-processes and the role of contamination (abstract). Meteorit. Planet. Sci. 57. [pdf]

• Regula A., Bloom H. E., Dauphas N., Davis A. M., Korsmeyer J. M., Krawczynski M. J., and Stephan T. (2022) Trace element ratios with CHILI: A progress report (abstract). Lunar Planet. Sci. 53, #2877. [pdf]

• Korsmeyer J. M., Stephan T., Davis A. M., Bloom H. E., MacPherson G. J., and Ivanova M. A. (2022) Molybdenum and ruthenium isotopic composition of a metal grain in a calcium–aluminum-rich inclusion from the Efremovka CV3 chondrite (abstract). Lunar Planet. Sci. 53, #2795. [pdf]

• Bloom H. E., Stephan T., Davis A. M., Heck P. R., Hoppe P., Korsmeyer J. M., and Amari S. (2022) s-Process molybdenum, ruthenium, and barium in high-density presolar graphite (abstract). Lunar Planet. Sci. 53, #2624. [pdf]

• Regula A., Bloom H. E., Dauphas N., Davis A. M., Korsmeyer J. M., Krawczynski M. J., Pellin M. J., Sheu S., and Stephan T. (2021) Toward trace element concentrations with CHILI (abstract). Meteorit. Planet. Sci. 56, A227 (#6287). [pdf]

• Stephan T., Bloom H. E., Davis A. M., Hoppe P., Korsmeyer J. M., Pellin M. J., Regula A., and Sheu S. (2021) Correlated molybdenum and ruthenium isotopes in presolar silicon carbide (abstract). Meteorit. Planet. Sci. 56, A252 (#6270). [pdf]