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Reply to Comment on "Testing Three-body Quantum Electrodynamics with Trapped Ti20+ Ions: Evidence for a Z-Dependent Divergence between Experiment and Calculation"
Published
Author(s)
Lawrence T. Hudson, C T. Chantler, M N. Kinnane, John D. Gillaspy, A.T. Payne, L F. Smale, Albert Henins, Joshua M. Pomeroy, J A. Kimpton, E Takacs, K Makonyi
Abstract
We find that Epps [1] hypothesis - namely that the current experimental data set is well represented by a small constant or zero offset from the predictions of Artemyev et al. [2] - is not supported by standard statistical analysis. We find that adding the new datum recommended by Epp makes the discrepancy that we reported earlier grow with Z even more strongly - rather than weakly, as Epp suggests. Our primary conclusion [3] of an apparent Z-dependent discrepancy between experiment and theory is unchanged, and is qualitatively novel com- pared to earlier discussion of discrepancies in QED. While Epp suggests that our results extrapolate to problems at very high-Z, we note that our present and previous datasets both include data up to and including Z = 92, and the reduced chi-squared χ2r values showed a negligible discrepancy of the fit over this range of Z. [1] S. W. Epp, Phys. Rev. Lett. (2013). [2] A. N. Artemyev, V. M. Shabaev, V. A. Yerokhin, G. Plunien, and G. Soff, Phys Rev A 71, 062104 (2005). [3] C. T. Chantler, M. N. Kinnane, J. D. Gillaspy, L. T. Hudson, A. T. Payne, L. F. Smale, A. Henins, J. M. Pomeroy, J. N. Tan, J. A. Kimpton, et al., Phys Rev Letts 109, 153001 (2012).
Hudson, L.
, Chantler, C.
, Kinnane, M.
, Gillaspy, J.
, , A.
, Smale, L.
, Henins, A.
, Pomeroy, J.
, Kimpton, J.
, Takacs, E.
and Makonyi, K.
(2013),
Reply to “Comment on "Testing Three-body Quantum Electrodynamics with Trapped Ti20+ Ions: Evidence for a Z-Dependent Divergence between Experiment and Calculation", Physical Review Letters
(Accessed October 8, 2025)