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تسجيل مستخدم جديدCSO and CARMA Observations of L1157. I. A Deep Search for Hydroxylamine (NH$_2$OH)
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A deep search for the potential glycine precursor hydroxylamine (NH$_2$OH) using the Caltech Submillimeter Observatory (CSO) at $lambda = 1.3$ mm and the Combined Array for Research in Millimeter-wave Astronomy (CARMA) at $lambda = 3$ mm is presented toward the molecular outflow L1157, targeting the B1 and B2 shocked regions. We report non-detections of NH$_2$OH in both sources. We a perform non-LTE analysis of CH$_3$OH observed in our CSO spectra to derive kinetic temperatures and densities in the shocked regions. Using these parameters, we derive upper limit column densities of NH$_2$OH of $leq1.4 times 10^{13}$~cm$^{-2}$ and $leq1.5 times 10^{13}$~cm$^{-2}$ toward the B1 and B2 shocks, respectively, and upper limit relative abundances of $N_{NH_2OH}/N_{H_2} leq1.4 times 10^{-8}$ and $leq1.5 times 10^{-8}$, respectively.
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