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arXiv · 1801.08796

H2O MegaMasers: a RadioAstron success story

Willem Baan·Alexey Alakoz·Tao An·Simon Ellingsen·Christian Henkel·Hiroshi Imai·Vladimir Kostenko·Ivan Litovchenko·James Moran·Andrej Sobolev·Alexander Tolmachev
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Abstract

The RadioAstron space-VLBI mission has successfully detected extragalactic H2O MegaMaser emission regions at very long Earth to space baselines ranging between 1.4 and 26.7 Earth Diameters (ED). The preliminary results for two galaxies, NGC3079 and NGC4258, at baselines longer than one ED indicate masering environments and excitation conditions in these galaxies that are distinctly different. Further observations of NGC4258 at longer baselines will reveal more of the physics of individual emission regions.

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Willem Baan, Alexey Alakoz, Tao An, Simon Ellingsen, Christian Henkel, Hiroshi Imai, Vladimir Kostenko, Ivan Litovchenko, James Moran, Andrej Sobolev, Alexander Tolmachev. 2018-01-29. H2O MegaMasers: a RadioAstron success story. https://doi.org/10.1017/s1743921317010869

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