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Measurement of the Kr XVIII 3d 2D5/2 lifetime in a Unitary Penning Trap
Published
Author(s)
Nicholas D. Guise, Joseph Tan, Samuel Brewer, Charlotte F. Fischer, P. Jonsson
Abstract
The lifetime of the 3d 2D5/2 in the fine-structure doublet of the Kr XVIII ground configuration is measured using a compact Penning trap with < 2.2 cm3 of trapping volume. Kr17+ ions produced in an electron beam ion trap (EBIT) are extracted and captured in this unitary Penning trap, isolating them with an energy distribution that is about a factor of 102 lower than in the EBIT ion source. The 637 nm photons emitted by the captured Kr XVIII ions are observed when the 3d 2D5/2 level decays via magnetic-dipole (M1) transition to the 3d 2D3/2 ground state. We measured the lifetime of the 3d 2D5/2 level to be 24.48 (28)stat (14)sys. At the one-percent level, this new technique is compared with a previous intra-EBIT experiment and various theoretical methods. Prospect for other experiments and higher accuracy is discussed.
Guise, N.
, Tan, J.
, Brewer, S.
, Fischer, C.
and Jonsson, P.
(2014),
Measurement of the Kr XVIII 3d 2D5/2 lifetime in a Unitary Penning Trap, Physical Review Letters, [online], https://doi.org/10.1103/PhysRevA.89.040502, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=914760
(Accessed October 11, 2025)