  YbRh2Si2 is a model system for quantum criticality. Particularly, Hall effect
measurements helped identify the unconventional nature of its quantum critical
point. Here, we present a high-resolution study of the Hall effect and
magnetoresistivity on samples of different quality. We find a robust crossover
on top of a sample dependent linear background contribution. Our detailed
analysis provides a complete characterization of the crossover in terms of its
position, width, and height. Importantly, we find in the extrapolation to zero
temperature a discontinuity of the Hall coefficient occurring at the quantum
critical point for all samples. Particularly, the height of the jump in the
Hall coefficient remains finite in the limit of zero temperature. Hence, our
data solidify the conclusion of a collapsing Fermi surface. Finally, we
contrast our results to the smooth Hall-effect evolution seen in Chromium, the
prototype system for a spin-density-wave quantum critical point.
