GeminiFocus 2013 Year in Review | Page 29

Nancy A. Levenson Science Highlights A diverse collection of scientific results were published with Gemini data in 2013. These highlights provide a sample of the types of cutting-edge science our users are doing. In this current issue, Science Highlights reports on the most powerful flare ever observed on an L dwarf, spiral patterns in a protoplanetary disk, and the properties of galaxies in intermediate-mass clusters. January 2014 The Most Powerful Flare ever Observed on an L Dwarf Astronomers used the Gemini Multi-Object Spectrograph on Gemini North to capture the most powerful flare ever observed on an L dwarf. At its peak, the brightness of the Jupitersized source increases by a factor of three, with a total flare energy output of 1.6 x 1032 ergs. The team suggests that similar flares may be common in this class of substellar objects, occurring once or twice per month. The Gemini data also provided the L1 spectral type of the brown dwarf, named WISE J190648.47+401106.8 for its discovery using NASA’s WISE satellite, or W1906+40 for short. Figure 1. Gemini spectrum of W1906+40, in its quiescent state (black) and during a strong flare (blue). In addition to the overall increase in luminosity, the Ha emission appears broad and the overall spectral shape corresponds to higher temperatures during the flare. (The spectra are not corrected for the effects of Earth’s atmosphere.) John Gizis (University of Delaware) and collaborators have been observing W1906+40 using the Kepler satellite and a variety of ground-based facilities. The long-term (15-month) January2014 2013 Year in Review GeminiFocus 27