A CMS luminosity monitor using single-crystal CVD diamond pixel detectors

The Pixel Luminosity Telescope (PLT) is an innovative luminosity monitor which is planned as an upgrade for the CMS detector at the LHC. It uses pixelated single-crystal diamonds as the active sensor material bumpbonded to standard CMS pixel readout electronics. The PLT makes use of a presently unused feature of the pixel readout chip which was designed to provide a hit-over-threshold signal to a hardware trigger processor. This feature will produce a bunch crossing (25 ns) 'hit' signal that can form the basis of luminosity information at the hardware level. We will report on the first successful use of this 'Fast-Or' signal to self-trigger on beta particles from a source using a diamond pixel detector. Expected performance of the PLT based on Pythia simulations is also detailed.