The LHCb test beam programme is motivated by the upgrade of the experiment scheduled for installation in 2018/19, which requires the redesign of major components of the existing tracking and particle identification systems. The first period (25 July to 6 August), at the T9 beam line, was dedicated to the commissioning of a new beam telescope based on Timepix3 silicon pixel detectors, which has been developed by the LHCb VELO Upgrade group with support by the Medipix collaboration.

The Timepix3 telescope has been tested as part of the LHCb test beam programme

Key features of the Timepix3 ASIC are high data rate (up to 10 million tracks/s), data-driven readout (in line with the readout scheme of the upgraded LHCb experiment), and the availability of both deposited charge and timing information for each 55 x 55 μm² pixel cell resulting in high spatial resolution and robust track reconstruction. During the two-week beam test, the Timepix3 telescope has shown excellent performance, with ~10⁹ tracks written to disk. In addition, the integration of an external device under test (strip detector with Beetle chip readout) with the telescope could be demonstrated successfully.

The groups are therefore well prepared for the upcoming test beam periods in October and November at the SPS H8 beam line which will be used for testing the rate capability of the Timepix3 ASIC, the characterisation of irradiated pixel and strip sensors, the testing of photo-detectors for the upgraded RICH as well as the qualification of fibres and photo-detectors for the scintillating fibre tracker.