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arXiv · 1806.07397

Mass Assembly of Stellar Systems and their Evolution with the SMA - 1.3 mm Subcompact Data Release

Abstract

We present the Mass Assembly of Stellar Systems and their Evolution with the SMA (MASSES) survey, which uses the Submillimeter Array (SMA) interferometer to map the continuum and molecular lines for all 74 known Class 0/I protostellar systems in the Perseus molecular cloud. The primary goal of the survey is to observe an unbiased sample of young protostars in a single molecular cloud so that we can characterize the evolution of protostars. This paper releases the MASSES 1.3 mm data from the subcompact configuration ($\sim$4$^{\prime\prime}$ or $\sim$1000 au resolution), which is the SMA's most compact array configuration. We release both $uv$ visibility data and imaged data for the spectral lines CO(2-1),$^{13}$CO(2-1), C$^{18}$O(2-1), and N$_2$D$^+$(3-2), as well as for the 1.3 mm continuum. We identify the tracers that are detected toward each source. We also show example images of continuum and CO(2-1) outflows, analyze C$^{18}$O(2-1) spectra, and present data from the SVS 13 star-forming region. The calculated envelope masses from the continuum show a decreasing trend with bolometric temperature (a proxy for age). Typical C$^{18}$O(2-1) linewidths are 1.45 km s$^{-1}$, which is higher than the C$^{18}$O linewidths detected toward Perseus filaments and cores. We find that N$_2$D$^+$(3-2) is significantly more likely to be detected toward younger protostars. We show that the protostars in SVS 13 are contained within filamentary structures as traced by C$^{18}$O(2-1) and N$_2$D$^+$(3-2). We also present the locations of SVS 13A's high velocity (absolute line-of-sight velocities $>$150 km s$^{-1}$) red and blue outflow components. Data can be downloaded from https://dataverse.harvard.edu/dataverse/MASSES .

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BibTeXRIS

Ian W. Stephens, Michael M. Dunham, Philip C. Myers, Riwaj Pokhrel, Tyler L. Bourke, Eduard I. Vorobyov, John J. Tobin, Sarah I. Sadavoy, Jaime E. Pineda, Stella S. R. Offner, Katherine I. Lee, Lars E. Kristensen, Jes K. Jørgensen, Alyssa A. Goodman, Héctor G. Arce, Mark Gurwell. 2018-06-19. Mass Assembly of Stellar Systems and their Evolution with the SMA - 1.3 mm Subcompact Data Release. https://doi.org/10.3847/1538-4365/aacda9

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