Expanding the precision timing frontier for particle tracking at hadron colliders

The large increase in the number of overlapping proton-proton interactions (pileup) is one of the leading experimental challenges for the HL-LHC physics program. A novel and powerful approach to mitigating the effects of the pileup is to use high-precision timing information to distinguish between collisions occurring very close in space but well-separated in time.

The development of novel detectors achieving both superb position resolution and a few tens of picoseconds timing is critical for operation in such environment. Low-gain avalanche diode sensors (LGADs) have shown suitable time response, but edge structures necessary to shape the internal electric field prevent the formation of small pixels. Furthermore, LGADs not yet radiation hard to operate in the innermost layers of the ATLAS ITk pixel detector or to be included in the upgrades for the LHCb experiment.

Other options under development to reach Ultra-Fast Timing are 3-D sensors where the electrodes penetrate the bulk, and novel monolithic sensors.

Improved instrumentation providing the necessary timing capability is needed to advance the development of these novel sensors for the upgrades of LHC experiments and experiments at future colliders. These new devices will bring revolutionary opportunities across all STFC's science areas and facilities, from Particle to Nuclear physics and Photon science.

This grant will allow procuring a 12-GHz signal generator and fast oscilloscope (7.8 ps per sample) which will enable to properly characterise ultra-fast silicon detectors (LGADs and 3D sensors) by enabling the operation of the sensors closer to realistic operating conditions as well as precise measurements of their (ultra-fast) response signals.