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arXiv · 1509.03779

CSO and CARMA Observations of L1157. I. A Deep Search for Hydroxylamine (NH$_2$OH)

Brett A. McGuire·P. Brandon Carroll·Niklaus M. Dollhopf·Nathan R. Crockett·Joanna F. Corby·Ryan A. Loomis·Andrew Burkhardt·Christopher Shingledecker·Geoffrey A. Blake·Anthony J. Remijan
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Abstract

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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Brett A. McGuire, P. Brandon Carroll, Niklaus M. Dollhopf, Nathan R. Crockett, Joanna F. Corby, Ryan A. Loomis, Andrew Burkhardt, Christopher Shingledecker, Geoffrey A. Blake, Anthony J. Remijan. 2015-09-12. CSO and CARMA Observations of L1157. I. A Deep Search for Hydroxylamine (NH$_2$OH). https://doi.org/10.1088/0004-637x%2F812%2F1%2F76

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