Study of an optical trigger to be used for beauty search in fixed target mode at the LHC

We propose research and development of an "Optical trigger" to be used for B-meson selection in an LHC fixed target experiment. The optical trigger relies on Cherenkov light detection using a fast photodetector. The device is in principle sensitive to charged particles with large impact parameter, arising from secondary vertices belonging to the B-meson chain, but blind to minimum bias events originating in a small target. A rejection factor of 50 to 100 of the unwanted minimum bias events is expected, with a good detection efficiency for B-meson-originating decays. This should permit operation of LHC fixed target experiments at the forecast high rate.