New Circumstellar Dust Creation in V838Monocerotis

摘要

We report high spatial resolution 11.2 pm and 18.1 pm imaging of the eruptive variableV838 Monocerotis, obtained with Gemini Observatory's Michelle in 2007 March. The 2007 fluxdensity of the unresolved stellar core is roughly 2 times brighter than that observed in 2004. Weinterpret these data as evidence that V838 Mon has experienced a new circumstellar dust creationevent. We also report a gap of spatially extended thermal emission over radial distances of 1860-93000 AU from the central source, which suggests that no prior significant circumstellar dustproduction events have occurred within the past ~900-1500 years.