The favorable apparition of comet C/2014 Q2 (Lovejoy), and unique insights from ground-based IR observations

In February 2015, we observed comet C/2014 Q2 (Lovejoy) on two consecutive nights, using NIRSPEC at the Keck Observatory, in Hawaii. Comet Q2 underwent strong activity and a favorable apparition, which triggered astronomical observing campaigns worldwide and yielded unique scientific results over a range of wavelength regimes. From the infrared (IR) observations we retrieve production rates, temperatures, cosmogonic parameters and abundances of native species (i.e. volatiles released directly from the nucleus) that are of unique importance in the interpretation of global properties and highly complementary to measurements performed at other wavelengths, both of native and product species in the coma. Our measurements show detection of several molecules we typically detect in the IR, and strong, unidentified lines. We also performed a deep search for HDO emission lines, yielding constraints of the D/H ratio. We will discuss our preliminary results in the context of complementary studies of C/2014 Q2 and compare the measured abundances with those in other comets.