اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of the lifetime of the $7s^2S_{1/2} $ state in atomic cesium using asynchronous gated detection
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We report a measurement of the lifetime of the cesium $7s,^2S_{1/2}$ state using time-correlated single-photon counting spectroscopy in a vapor cell. We excite the atoms using a Doppler-free two-photon transition from the $6s,^2S_{1/2}$ ground state, and detect the 1.47$mu$m photons from the spontaneous decay of the $7s,^2S_{1/2}$ to the $6p,^2P_{3/2}$ state. We use a gated single photon detector in an asynchronous mode, allowing us to capture the fluorescence profile for a window much larger than the detector gate length. Analysis of the exponential decay of the photon count yields a $7s,^2S_{1/2}$ lifetime of 48.28$pm$0.07ns, an uncertainty of 0.14%. These measurements provide sensitive tests of theoretical models of the Cs atom, which play a central role in parity violation measurements.
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We report a measurement of the ratio of electric dipole transition matrix elements of cesium for the $6p,^2P_{1/2} rightarrow 7s,^2S_{1/2}$ and $6p,^2P_{3/2} rightarrow 7s,^2S_{1/2}$ transitions. We determine this ratio of matrix elements through com
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Using recent high-precision measurements of electric dipole matrix elements of atomic cesium, we make an improved determination of the scalar ($alpha$) and vector ($beta$) polarizabilities of the cesium $6s ^2S_{1/2} rightarrow 7s ^2S_{1/2} $ trans
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We report measurements of the electric dipole matrix elements of the $^{133}$Cs $ $ $6s,^2S_{1/2} rightarrow 7p,^2P_{1/2}$ and $6s,^2S_{1/2} rightarrow 7p,^2P_{3/2}$ transitions. Each of these determinations is based on direct, precise comparisons of
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