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تسجيل مستخدم جديدALMA spectroscopic detection of water vapour in the atmosphere of the giant gas planet Jupiter
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In the Jovian atmosphere, the trace species are detected for the first time after the collision of comet Shoemaker-Levy 9 near 44$^circ$S in July 1994. Most of these trace species are detected with spectroscopic millimeter/submillimeter observation. In the atmosphere of Jupiter, trace gases play an important role in atmospheric chemistry with heterogeneous and homogeneous chemical reactions, interaction with radiation, and phase transition. Here we present the first spectroscopic detection of the rotational emission line of water (H$_{2}$O) in the atmosphere of Jupiter at frequency $ u$ = 183.310 GHz with molecular transition J = 3$_{1,3}$$-$2$_{2,2}$ using Atacama Large Millimeter/Submillimeter Array (ALMA). The statistical column density of water emission line is N(H$_{2}$O)$sim$4$times$10$^{15}$ cm$^{-2}$. The rotational emission line of H$_{2}$O is found in the stratosphere of Jupiter with $geq$3$sigma$ statistical significance. The column density of H$_{2}$O corresponds to the fractional abundance relative to H$_{2}$ is f(H$_{2}$O)$sim$ 4$times$10$^{-9}$.
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