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تسجيل مستخدم جديدALMA detection of water vapour in the low mass protostar IRAS 16293$-$2422
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The low mass protostar IRAS 16293$-$2422 is a well-known young stellar system that is observed in the L1689N molecular cloud in the constellation of Ophiuchus. In the interstellar medium and solar system bodies, water is a necessary species for the formation of life. We present the spectroscopic detection of the rotational emission line of water (H$_{2}$O) vapour from the low mass protostar IRAS 16293$-$2422 using the Atacama Large Millimeter/submillimeter Array (ALMA) band 5 observation. The emission line of H$_{2}$O is detected at frequency $ u$ = 183.310 GHz with transition J=3$_{1,3}$$-$2$_{2,2}$. The statistical column density of the emission line of water vapour is $N$(H$_{2}$O) = 4.2$times$10$^{16}$ cm$^{-2}$ with excitation temperature ($T_{ex}$) = 124$pm$10 K. The fractional abundance of H$_{2}$O with respect to H$_{2}$ is 1.44$times$10$^{-7}$ where $N$(H$_{2}$) = 2.9$times$10$^{23}$ cm$^{-2}$.
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