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arXiv · 1812.09454

Multi-epoch VLBI of a double maser super burst

Ross A. Burns·Olga Bayandina·Gabor Orosz·Mateusz Olech·Katharina Immer·Jay Blanchard·Benito Marcote·Huib van Langevelde·Tomoya Hirota·Kee-Tae Kim·Irina Valtts·Nadya Shakhvorostova·Georgij Rudnitskii·Alexandr Volvach·Larisa Volvach·Gordon MacLeod·James O. Chibueze·Gabriele Surcis·Busaba Kramer·Willem Baan·Crystal Brogan·Todd Hunter·Stan Kurtz
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Abstract

In a rare and spectacular display, two well-known massive star forming regions, W49N and G25.65+1.05, recently underwent maser 'super burst' - their fluxes suddenly increasing above 30,000 and 18,000 Jy, respectively, reaching several orders of magnitude above their usual values. In quick-response, ToO observations with the EVN, VLBA and KaVA were obtained constituting a 4 week campaign - producing a high-cadence multi-epoch VLBI investigation of the maser emission. The combination of high-resolution, polarisation and flux monitoring during the burst provides one of the best accounts, to date, of the maser super burst phenomenon, aiding their use as astrophysical tools. These proceedings contain the preliminary results of our campaign.

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Ross A. Burns, Olga Bayandina, Gabor Orosz, Mateusz Olech, Katharina Immer, Jay Blanchard, Benito Marcote, Huib van Langevelde, Tomoya Hirota, Kee-Tae Kim, Irina Valtts, Nadya Shakhvorostova, Georgij Rudnitskii, Alexandr Volvach, Larisa Volvach, Gordon MacLeod, James O. Chibueze, Gabriele Surcis, Busaba Kramer, Willem Baan, Crystal Brogan, Todd Hunter, Stan Kurtz. 2018-12-22. Multi-epoch VLBI of a double maser super burst. https://arxiv.org/abs/1812.09454

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