Timing performance of the LHCb VELO Timepix3 Telescope

TL;DR

This study enhances the timing resolution of the LHCb VELO Timepix3 Telescope using a novel correction method, improving precision from 438 ps to 276 ps in a high-energy beam test.

Contribution

A new two-step correction method was developed to significantly improve the timing resolution of the Timepix3 sensor in particle tracking.

Findings

Timing resolution improved from 438 ps to 276 ps.

Systematic timing offsets were effectively corrected.

Method demonstrated in a 180 GeV/c hadron beam at CERN SPS.

Abstract

We performed a detailed study of the timing performance of the LHCb VELO Timepix3 Telescope with a 180 GeV/c mixed hadron beam at the CERN SPS. A twofold method was developed to improve the resolution of single-plane time measurements, resulting in a more precise overall track time measurement. The first step uses spatial information of reconstructed tracks in combination with the measured signal charge in the sensor to correct for a mixture of different effects: variations in charge carrier drift time; variations in signal induction, which are the result of a non-uniform weighting field in the pixels; and lastly, timewalk in the analog front-end. The second step corrects for systematic timing offsets in Timepix3 that vary from -2 ns to 2 ns. By applying this method, we improved the track time resolution from 438$\,\pm\,$16 ps to 276$\,\pm\,$4 ps.