Benjamin Jacobsen

Portrait of  Benjamin Jacobsen

  • Title
    Staff Scientist/Research Staff
  • Email
    jacobsen5@llnl.gov
  • Phone
    (925) 422-1952
  • Organization
    Not Available

Research Interests

Ben’s research interests are primarily in isotope geo/cosmochemistry, nuclear forensics, and secondary ion mass spectrometry. He uses SIMS to investigate chemical and isotopic signatures for an array of early solar system and nuclear forensics materials. 

Professional Background

Ben Jacobsen is a research scientist in the Nuclear and Chemical Sciences Division and is a member of the Chemical and Isotopic Signatures Group. He started at LLNL as a postdoctoral researcher with a background in isotope cosmochemistry and geochemistry. As a postdoctoral researcher, using secondary ion mass spectrometry (SIMS), Ben conducted in situ isotopic and chemical analyses of primordial solar nebular objects found in primitive meteorites to understand their chronological and compositional evolution within the early solar system. As a staff scientist, he continued using SIMS analyses for a variety of innovative research applications in nuclear forensics, material science, geochemistry, and cosmochemistry. Ben has over 20 years of mass spectrometry experience and over 15 years of experience using dynamic SIMS instruments such as the ims-3f/4f, NanoSIMS 50, and ims-1270. He has been the lead analyst for the 3f/4f laboratory at LLNL since 2018 and is also a key member of the NanoSIMS laboratory. 

Ph.D., Geology, University of California at Davis, 2009

M.S., Geology, University of Copenhagen, 2002

B.S., Geology, University of Copenhagen, 2000

  1. Han, J., Jacobsen, B., Liu, M.-L., Brearley, A.J., Matzel, J.E., & Keller, L.P. (2019) Origin of 16O-rich Fine-Grained Ca-Al-Rich Inclusions of Different Mineralogy and Texture. Geochemistry, 79, p125543. 

  2. Weisz, D.G., Jacobsen, B., Marks, N.E., Knight, K.B., Isselhardt, B.H., & Matzel, J.E. (2018) Diffusive Mass Transport in Agglomerated Glassy Fallout from a Near-Surface Nuclear Test. Geochimica et Cosmochimica Acta, 223, 377-388. 

  3. Weisz, D.G., Jacobsen, B., Marks, N.E., Knight, K.B., Isselhardt, B.H. Matzel, J.E., Weber, P.K., Prussin, S.G. & Hutcheon, I.D. (2017) Deposition of Vaporized Species onto Glassy Fallout from a Near-Surface Nuclear Test. Geochimica et Cosmochimica Acta, 201, 410-426. 

  4. Novella, D., Jacobsen, B. Weber, P.K., Tyburczy, J.A., Ryerson, F.J., & Du Frane, W.L. (2017) Hydrogen Self-Diffusion in Single Crystal Olivine and Electrical Conductivity of the Earth’s Mantle. Scientific Reports, Science, 7, 1-10 

  5. Kita, N. T., Yin, Q.-Z., MacPherson, G. J., Ushikubo, T., Jacobsen, B., Nagashima, K., Kurahashi, E., Krot, A. N., & Jacobsen, S. B. (2013) 26Al-26Mg isotope Systematics of First Solids in the Early Solar System. Meteoritics and Planetary Science, 48, 1383-1400. 

  6. Simon, S.B., Davis, A.M., Hutcheon, I.D. & Jacobsen, B. (2012) Cosmochemistry. In McGraw-Hill Encyclopedia of Science and Technology, 11th edition, 4, 817-828. 

  7. Jacobsen, B., Matzel, J., Hutcheon, I.D., Krot, A.N., Yin, Q.-Z, Nagashima, K., Ramon, E., Weber, P., Ishii, H.A., & Ciesla, F. (2011) Formation of the Short-Lived Radionuclide 36Cl in the Protoplanetary Disk During Late-Stage Irradiation of a Volatile-Rich Reservoir. Astrophysical Journal, 731, L28 (p1-4). 

  8. Shen, B., Jacobsen, B., Lee, C.-T., Yin, Q.-Z., & Morton, D.M. (2009) The Mg Isotopic Signature of Granites and the Role of Weathering in Continent Formation. Proceedings of the National Academy of Sciences, 106, 20652-20657. 

  9. Jacobsen, B., Yin, Q.-Z., Moynier, F., Amelin, Y., Krot, A.N., Nagashima, K., Hutcheon, I.D., & Palme, H. (2008) 26Al-26Mg and 207Pb-206Pb Systematics of Allende CAIs: Canonical Solar Initial 26Al/27Al Ratio Reinstated. Earth and Planetary Science Letters, 272, 353-364. 

  10. Debaille, V., Brandon, A.D., Yin, Q.Z., & Jacobsen, B. (2007) Coupled 142Nd-143Nd Evidence for a Protracted Magma Ocean in Mars. Nature, 450, 525-528. 

  11. Yin, Q.-Z., Jacobsen, B., Moynier, F., & Hutcheon, I.D. (2007) Toward Consistent Chronology in the Early Solar System: High-Resolution 53Mn-53Cr Chronometry for Chondrules. Astrophysical Journal, 662, L43-L46. 

  12. Kent, A. J. R., Jacobsen, B., Peate, D. W., Waight, T. E., & Baker, J. A. (2004) Isotope dilution MC-ICP-MS Rare Earth Element Analysis of Geochemical Reference Materials NIST SRM 610, NIST SRM 612, NIST SRM 614, BHVO-2G, BHVO-2, BCR-2G, JB-2, WS-E, W-2, AGV-1 and AGV-2. Geostandards and Geoanalytical Research, 28, 417-429.