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arXiv · 2004.06732

Resolving nearby dust clouds

R. H. Leike·M. Glatzle·T. A. Enßlin
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Abstract

Aims: Mapping the interstellar medium in 3D provides a wealth of insights into its inner working. The Milky Way is the only galaxy for which detailed 3D mapping can be achieved in principle. In this paper, we reconstruct the dust density in and around the local super-bubble. Methods: The combined data from surveys such as Gaia, 2MASS, PANSTARRS, and ALLWISE provide the necessary information to make detailed maps of the interstellar medium in our surrounding. To this end, we used variational inference and Gaussian processes to model the dust extinction density, exploiting its intrinsic correlations. Results: We reconstructed a highly resolved dust map, showing the nearest dust clouds at a distance of up to 400pc with a resolution of 1pc. Conclusions: Our reconstruction provides insights into the structure of the interstellar medium. We compute summary statistics of the spectral index and the 1-point function of the logarithmic dust extinction density, which may constrain simulations of the interstellar medium that achieve a similar resolution.

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R. H. Leike, M. Glatzle, T. A. Enßlin. 2020-04-14. Resolving nearby dust clouds. https://doi.org/10.1051/0004-6361%2F202038169

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