The upgraded LHCb VELO silicon vertex detector is a lightweight hybrid pixel detector capable data driven readout at a luminosity of 2 x 10³³ cm^-2 s^-1 at the bunch crossing rate of  30 MHz. 

The track reconstruction speed and precision is enhanced relative to the first VELO detector even at the high multiplicity conditions of the upgrade, due to the pixel geometry and a closest distance of approach to the LHC beams of just 5.1 mm for the first sensitive element.

Cooling is provided by evaporative CO₂ circulating microchannel cooling substrates. The  whole detector contains 41 million 55 µm by 55 µm pixels. Each detector assembly is read out by three custom developed VeloPix front end ASICs. Each ASIC is designed to cope with almost 1 billion hits per second.

The VELO upgrade has been described in the Technical Design Report , submitted in November 2013 which lays out the planned construction and installation, and gives an overview of the expected detector performance. Some key figures and diagrams related to the VELO Upgrade can be found on our collection at Material for Presentations.