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Jacqueline L. Mann (Fed)

Physical Scientist

Dr. Jacqueline Mann received her M.S. and Ph.D. in Geology from University of Maryland, College Park under the direction of Dr. Karen Prestegaard and Dr. Robert Kelly (NIST). Dr. Mann is a Physical Scientist in the Inorganic Chemical Metrology Group at the National Institute of Standards and Technology (NIST) in Gaithersburg, MD. She has over 20 years of inorganic elemental and isotopic analysis experience at NIST, with 20 of those years involving the certification of Standard Reference Materials (SRMs) including, nuclear forensic, fossil fuel, clinical, and environmental SRMs. Here current work continues to focus on identifying and delivering the isotope metrology tools needed by various stakeholders, including the isotope Metallomics community, and building a comprehensive Isotope Metrology Program within NIST that leverages the relevant metrology expertise across NIST to more effectively meet the isotope metrology needs of the many isotope user communities.




MML Accolades – Collaboration and Teamwork Award (2022)

MML Accolades – Strategic Partnership Award (2016)


New determination of the 229Th half-life

Richard Essex, Jacqueline L. Mann, Ronald Colle, Lizbeth Laureano-Perez, Megan E. Bennett, Heather Dion, Ryan P. Fitzgerald, Amy M. Gaffney, Amelie Hubert, Robert E. Steiner, Ross W. Williams, Alkiviadis Gourgiotis, William S. Kinman
A new determination of the 229Th half-life was made based on measurements of the 229Th massic activity of a high-purity solution for which the 229Th molality

New thorium-229 standard reference material

Richard Essex, Jacqueline L. Mann, Ross W. Williams, William S. Kinman, Amelie Hubert, Megan E. Bennett
A new reference material, preliminarily designated as SRM 3059, was characterized for 229Th molality (mol•g-1) and thorium isotope amount ratios. This SRM is
Created October 9, 2019, Updated February 6, 2023