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تسجيل مستخدم جديدLifetime measurement of the 5d$^2$D$_{5/2}$ state in Ba$^+$
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The lifetime of the metastable 5d$^2$D$_{5/2}$ state has been measured for a single trapped Ba$^+$ ion in a Paul trap in Ultra High Vacuum (UHV) in the 10$^{-10}$ mbar pressure range. A total of 5046 individual periods when the ion was shelved in this state have been recorded. A preliminary value $tau_{D_{5/2}} = 26.4(1.7)$~s is obtained through extrapolation to zero residual gas pressure.
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We measure the lifetime of the cesium $5^2D_{5/2}$ state using a time-resolved single-photon-counting method. We excite atoms in a hot vapor cell via an electric quadrupole transition at a wavelength of $685,mathrm{nm}$ and record the fluorescence of
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