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arXiv · 1904.10895

Sulfur Chemistry in L1157-B1

Jonathan Holdship·Izaskun Jimenez-Serra·Serena Viti·Claudio Codella·Milena Benedettini·Francesco Fontani·Linda Podio·Mario Tafalla·Rafael Bachiller·Cecilia Ceccarelli
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Abstract

The main carrier of sulfur in dense clouds, where it is depleted from the gas phase, remains a mystery. Shock waves in young molecular outflows disrupt the ice mantles and allow us to directly probe the material that is ejected into the gas phase. A comprehensive study of sulfur-bearing species towards L1157-B1, a shocked region along a protostellar outflow, has been carried out as part of the IRAM-30m large program ASAI. The dataset contains over 100 lines of CCS, H$_2$CS, OCS, SO, SO$_2$ and isotopologues. The results of these observations are presented, complementing previous studies of sulfur-bearing species in the region. The column densities and fractional abundances of these species are measured and together these species account for 10\% of the cosmic sulfur abundance in the region. The gas properties derived from the observations are also presented, demonstrating that sulfur bearing species trace a wide range of different gas conditions in the region.

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Jonathan Holdship, Izaskun Jimenez-Serra, Serena Viti, Claudio Codella, Milena Benedettini, Francesco Fontani, Linda Podio, Mario Tafalla, Rafael Bachiller, Cecilia Ceccarelli. 2019-04-24. Sulfur Chemistry in L1157-B1. https://doi.org/10.3847/1538-4357%2Fab1cb5

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