  We performed an angle-resolved photoemission spectroscopy study of the
BiS2-based superconductor Nd(O,F)BiS2. Two small electron-like Fermi surfaces
around X (pi, 0) are observed, which enclose 2.4% and 1.1% of the Brillouin
zone area, respectively, corresponding to an electron doping of 7% per Bi site.
The low-energy spectrum consists of a weakly-dispersing broad hump and a
dispersive branch, which follows well the calculated band dispersion. This hump
is drastically suppressed with increasing temperature, while the dispersive
branch is essentially unaffected. The anomalous thermal effect indicates a
highly interacting electronic state, in which the superconducting pairing
develops.
