Speaker
Description
With the Upgrade II programme, LHCb plans to upgrade its detector with a target of 2034. It will operate at luminosities of up to 1.5x10$^{34}cm^{-2}s^{-1}$, accumulating over 300 fb$^{-1}$. This will result in about 42 interactions per crossing, producing approximately 2000 charged particles within the detector acceptance.
This higher luminosity requires a new VErtex LOcator (VELO) design capable of handling the increased data rates, radiation levels, and occupancies. New techniques are needed to assign b hadrons to their primary vertices and perform real-time pattern recognition, involving a new 4D hybrid pixel detector with advanced rate and timing capabilities.
Prototype front-end ASICs are being designed in 28 nm technology to handle these extreme hit rates and integrate timing information per pixel. This upgrade requires the sensors to provide time measurements with 35 ps resolution and be resistant to 2.5x10$^{16}$ 1 MeV n$_{eq}$cm$^{-2}$, all while maintaining a spatial resolution per plane of below 11 µm. 3D sensors with multiple different fast timing-motivated designs are being produced and characterised to fulfil this need.
The change from planar to 3D sensors will impact the overall design of the VELO detector due to their inherent characteristics. 3D sensors have reduced overall efficiency from passive material acting as dead areas, which can be partially recovered by angling the sensors with respect to the beam. Angling the 3D sensors also impacts the hit rate and spatial resolution expected at different radii. In addition, the high capacitance of 3D sensors increases the timing jitter expected, which is highly dependent on the 3D sensor design.
This presentation will highlight the promising technologies being investigated for the VELO HL-LHC upgrade, emphasising timing precision for vertexing within next-generation detectors. Recent characterisation results of 3D sensors will be presented, as well as simulation studies considering the impact of 3D sensor usage on the subdetector performance and design.
| Position | Postdoctoral 'Quest' researcher |
|---|---|
| Affiliation | CERN |
| Country | Switzerland |