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Mark Tyra (Fed)

I enjoy solving geological and chemical problems with multivariate tools such as mass spectrometry, chemical analysis, computational analysis, collaboration, and diligence. I have ten years of chemical and mass spectrometry experience analyzing both stable isotopes and radiogenic isotopes. At the National Institute of Standards and Technology (NIST), I serve as a postdoctoral researcher evaluating radioactive reference materials for use in nuclear forensics and by industry. This work will include the installation and testing of a HR ICPMS to be used to improve standard evaluation from an activity basis to a mass basis. Much of this work, in partnership with the National Technical Nuclear Forensics Center and partners, helps ensure the nuclear forensic capabilities of the U.S. remain robust. Prior to my arrival at NIST I used extinct short-lived radionuclides that were active when the solar system was young to determine the age of minerals that precipitated from water in asteroids. This work, along with compositional and stable isotope data, allows a history of water in the early solar system to be constructed. This work depended upon the collaboration of others, including those from the University of New Mexico, the California Institute of Technology, and Lawrence Livermore National Laboratory.

Professional Affiliations and Service

In addition to NIST, I am a visiting scientist professional at Lawrence Livermore National Laboratory. I am a member of the American Association for the Advancement of Science, American Geophysical Union, Geological Society of America, and the Meteoritical Society. Furthermore, I have chaired sessions at the Lunar and Planetary Science conference and the annual Meteoritical Society Annual Meeting. I serve as an occasional reviewer for the journals Geochimica et Cosmochimica Acta and Earth and Planetary Science Letters.


Limits on Strongly Interacting Sub-GeV Dark Matter from the PROSPECT Reactor Antineutrino Experiment

Hans Pieter Mumm, Denis E. Bergeron, Mark Tyra, Jerome LaRosa, Svetlana Nour, M Andriamirado, A.B. Balantekin, H.R. Band, C.D. Bass, D. Berish, N.S. Bowden, J.P. Brodsky, C.D. Bryan, T. Classen, A.J. Conant, G. Deichert, M.V. Diwan, M.J. Dolinski, A. Erickson, B.T. Foust, J.K. Gaison, A. Galindo-Uribarri, C.E. Gilbert, B.W. Goddard, B.T. Hackett, S. Hans, A.B. Hansell, K.M. Heeger, D.E. Jaffe, X. Ji, D.C. Jones, O. Kyzylova, C.E. Lane, T.J. Langford, B.R. Littlejohn, X. Lu, J. Maricic, M.P. Mendenhall, A.M. Meyer, R. Milincic, I. Mitchell, P.E. Mueller, J. Napolitano, C. Nave, R. Neilson, J.A. Nikkel, D. Norcini, J.L. Palomino, D.A. Pushin, X. Qian, E. Romero-Romero, R. Rosero, P.T. Surukuchi, R.L. Varner, D. Venegas-Vargas, P.B. Weatherly, C. White, J. Wilhelmi, A. Woolverton, M. Yeh, A. Zhang, C. Zhang, X. Zhang
If dark matter has mass lower than around 1 GeV, it will not impart enough energy to cause detectable nuclear recoils in many direct-detection experiments
Created October 3, 2019, Updated December 8, 2022