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تسجيل مستخدم جديدStark deceleration of NO radicals
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We report on the Stark deceleration of a pulsed molecular beam of NO radicals. Stark deceleration of this chemically important species has long been considered unfeasible due to its small electric dipole moment of 0.16 D. We prepared the NO radicals in the X 2{Pi}3/2, v=0, J=3/2 spin-orbit excited state from the X 2{Pi}1/2, v=0, J=1/2 ground state by Franck-Condon pumping via the A 2{Sigma}+ state. The larger effective dipole moment in the J=3/2 level of the X 2{Pi}3/2, v=0 state, in combination with a 316-stages-long Stark decelerator, allowed us to decelerate NO radicals from 315.0 m/s to 229.2 m/s, thus removing 47 % of their kinetic energy. The measured time-of-flight profiles of the NO radicals exiting the decelerator show good agreement with the outcome of numerical trajectory simulations.
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