  We report on a multiwavelength observational campaign of the black hole X-ray
binary Swift J1753.5-0127 that consists of an ESO/X-shooter spectrum supported
by contemporaneous Swift/XRT+UVOT and ATCA data. ISM absorption lines in the
X-shooter spectrum allows us to determine E(B-V)=0.45+/-0.02 along the
line-of-sight to the source. We also report detection of emission signatures of
He II at 4686 angstrom, H alpha, and, for the first time, H I at 10906 angstrom
and Paschen Beta. The double-peaked morphology of these four lines is typical
of the chromosphere of a rotating accretion disk. Nonetheless, the paucity of
disk features points towards a low level of irradiation in the system. This is
confirmed through spectral energy distribution modeling and we find that the
UVOT+X-shooter continuum mostly stems from the thermal emission of a viscous
disk. We speculate that the absence of reprocessing is due to the compactness
of an illumination-induced envelope that fails to reflect enough incoming hard
X-ray photons back to the outer regions. The disk also marginally contributes
to the Compton-dominated X-ray emission and is strongly truncated, with an
inner radius about a thousand times larger than the black hole's gravitational
radius. A near-infrared excess is present, and we associate it with synchrotron
radiation from a compact jet. However, the measured X-ray flux is significantly
higher than what can be explained by the optically thin synchrotron jet
component. We discuss these findings in the framework of the radio quiet versus
X-ray bright hypothesis, favoring the presence of a residual disk, predicted by
evaporation models, that contributes to the X-ray emission without enhancing
the radio flux.
