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Joseph N. Tan (Fed)

Research Interests

  • trapping, cooling, and spectroscopy of exotic ions
  • order in plasmas cooled to low temperature (& driven far from equilibrium)
  • precision measurements and tests of QED or the standard model


Background and blended spectral line reduction in precision spectroscopy of EUV and x-ray transitions in highly charged ions

Yuri Ralchenko, Joseph N. Tan, Aung S. Naing, Galen O'Neil, Paul Szypryt, Dipti Dipti, Grant Mondeel, Roshani Silwal, Alain Lapierre, Steven Blundell, Gerald Gwinner, Antonio Camargo Villari, Endre Takacs
We report a method in EBIT spectral analysis that reduces signal from contaminant lines of 1 known or unknown origin. We utilize similar ion charge

Analysis of E3 Transitions in Ag-like High-Z Ions Observed with the NIST EBIT

Yuri Ralchenko, David La Mantia, Aung S. Naing, Paul Szypryt, Joseph N. Tan, Endre Takacs, Dipti Dipti, Yang Yang, Adam Hosier, Hunter Staiger
We report measurements and identification of the E3 4f$_7/2,5/2}$-5s$_1⁄2$ transitions and E1 allowed transitions in Ag-like W (Z=74), Re (Z=75), and Ir (Z=77)

Measurement of the 2P1/2–2P3/2 fine structure splitting in fluorine-like Kr, W, Re, Os and Ir

Galen O'Neil, Samuel C. Sanders, Paul Szypryt, Dipti Goyal, Amy Gall, Yang Yang, Samuel M. Brewer, W.Bertrand (Randy) Doriese, Joseph Fowler, Daniel Swetz, Joseph N. Tan, Joel Ullom, Andrey V. Volotka, Endre Takacs, Yuri Ralchenko
Quantum electrodynamics (QED) is currently considered to be one of the most accurate theories of fundamental interactions. As its extraordinary precision offers
Created October 9, 2019, Updated December 8, 2022