Measurement of the branching fractions and lifetime of the5D5/2level ofBa+

Abstract

We present a measurement of the branching fractions for decay from the long-lived 5D 5/2 level in 138 Ba + . The branching fraction for decay into the 6S 1/2 ground state was found to be 0.846(25)stat (4)sys. We also report an improved measurement of the 5D 5/2 lifetime, τ5D 5/2 = 31.2(0.9) s. Together these measurements provide the first experimental determination of transition rates for decay out of the 5D 5/2 level. The low (< 7 × 10 −12 Torr) pressure in the ion trap in which these measurements were made simplified data acquisition and analysis. Comparison of the experimental results with theoretical predictions of the transition rates shows good agreement.

Lifetime measurement of the 5d2 D 5/2 state in Ba+

“…The measured value is preliminary because cross checks for systematics are still ongoing. Our result agrees within 2σ with the most recent theoretical value τ D 5/2 = 29.8(3) s [6] and with the latest independent experimental value of τ D 5/2 = 31.2(9) s [15]. Figure 6 displays the time evolution of the measurements and the theory values for the lifetime of the 5d 2 D 5/2 state in a Ba + ion.…”

“…The lifetime of the metastable 5d 2 D 5/2 state in Ba + has been measured earlier in different experiments [10][11][12][13][14][15][16]. Calculations are presently performed by different independent theory groups [5,6,[17][18][19][20][21].…”

Precision measurement of the branching fractions of the5pP1/22state inSrLikforman1, Tugayé2, Guibal3 et al. 2016Phys. Rev. A19180View full textAdd to dashboardCite

“…By restricting ourselves to the case of heavier alkali-earth (i.e. species with D metastable states), these techniques have been recently applied to obtain precision measurements of spectroscopical quantities on laser-cooled 40 Ca + ions [9][10][11][12], 138 Ba + ions [13][14][15], and 88 Sr + ions [16][17][18][19]. In this paper we present the precision measurement of the branching fractions for the decay of the 5p 2 P 1/2 state of 88 Sr + .…”

Precise determination of the quadrupole transition matrix element ofCa+40via branching-fraction and lifetime measurements

“…The decay probability P obeys the exponential law P = e −∆t/τ 5/2 , where τ 5/2 is the 3d 2 D 5/2 state lifetime. Meanwhile, once the ion is shelved to 3d 2 D 5/2 , it can decay not only to the 4s 2 S 1/2 ground state with the branching ratio Γ but also to the 3d 2 D 3/2 state with the branching ratio 1-Γ [22]. Figure 1 (b) shows a simplified sequence for the lifetime and branching ratio measurements.…”