Does intrinsic graphene have a gap? Although the tight-binding Dirac cone band structure suggests no, interactions and other effects have been predicted to open up a gap [Castro Neto RMP]. It is too small to be probed by photo-emission spectroscopy, and dc transport experiments on high quality suspended graphene may not be adequate to detect it [Geim]. For extrinsic graphene, placed on hexagonal boron nitride (hBN) and near a conducting plane, gap opening has already been shown [Goldhaber-Gordon, Kim], but the origin of the insulating state is not completely understood.  The Josephson junction spectrometer has the sensitivity and energy resolution to investigate gapped graphene. High quality graphene samples may be coupled to the spectrometer capacitively over a large bandwidth. The spectrometer may detect enhanced absorption at the “gap edge” indicating the presence of an insulating state.