Abstract : The SuperKEKB e+e- collider aims to reach a very high
luminosity of 8 1035 cm-2s-1, using strongly focused ultra-
low emittance bunches colliding every 4ns. A fast
luminosity monitoring system is required for luminosity
feedback and control in the presence of dynamic imperfections,
as well as for luminosity optimisation. A relative
precision of about 10−3 in 1ms is specified, which can be
achieved thanks to the very large cross-section of the radiative Bhabha process at zero degree scattering angle. The technology
used is based on diamond sensors, to be placed just outside the beam pipe, downstream of the interaction point, at
locations with event rates consistent with the aimed precision and small enough contamination from single-beam particle
losses. We will present estimates of the precisions which can be effectively reached considering several beam-pipe geometries
and materials at the selected location, along with a preliminary study of single beam losses expected at the detector
location. The status of on-going testing and preparation of the first diamond sensor and fast readout electronics to be used
in the single beam commissioning phase will also be reported.
