A High-Granularity Timing Detector for the ATLAS Phase-II upgrade

Mar 14, 2023, 2:25 PM
30m
Bldg 53 / Room 1320 - Panofsky Auditorium (SLAC)

Bldg 53 / Room 1320 - Panofsky Auditorium

SLAC

2575 Sand Hill Rd Menlo Park, CA USA
Invited Tracking Tracking

Speaker

Stefan Guindon (CERN)

Description

The increase of the particle flux (pile-up) at the HL-LHC with instantaneous luminosities up to L ≃ 7.5 × 10$^{34}$ cm$^{−2}$s$^{−1}$ will have a severe impact on the ATLAS detector reconstruction and trigger performance. The end-cap and forward region where the liquid Argon calorimeter has coarser granularity and the inner tracker has poorer momentum resolution will be particularly affected. A High Granularity Timing Detector (HGTD) will be installed in front of the LAr end-cap calorimeters for pile-up mitigation and luminosity measurements.
The HGTD is a novel detector introduced to augment the new all-silicon Inner Tracker in the pseudo-rapidity range from 2.4 to 4.0, adding the capability to measure charged-particle trajectories in time as well as space. Two silicon-sensor double-sided layers will provide precision timing information for minimum-ionising particles with a resolution as good as 30 ps per track in order to assign each particle to the correct vertex. Individual sensor pads will have a size of 1.3 mm × 1.3 mm, leading to a highly granular detector with 3.7 million individual channels. Low Gain Avalanche Detectors (LGAD) technology has been chosen as it provides enough gain to reach the large signal over noise ratio needed.
The requirements and overall specifications of the HGTD will be presented as well as the technical design and the project status. The on-going R&D effort carried out to study the sensors, the readout ASIC, and the other components, supported by laboratory and test beam results, will also be presented.

Primary author

Presentation materials