Interacting binaries: Science cases where simultaneous multicolor medium‐resolution spectroscopy makes a difference

This contribution to “The 1st year of science with X‐shooter” conference illustrates 2 different applications of the new ESO multi‐waveband spectrograph to the study of interacting binaries. In particular we present spectra collected during the late decline of U Sco 2010 outburst and during a low/hard X‐ray phase of the black hole candidate GX339‐4. In both cases the unprecedented spectral coverage and resolution offered by X‐shooter have unveiled unexpected features (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)