26-30 July 2021
Europe/Berlin timezone

A GPU High Level Trigger 1 for the upgraded LHCb detector

28 Jul 2021, 10:45


Parallel session talk Detector R&D and Data Handling T12: Detector R&D and Data Handling


Marianna Fontana


In 2022 the upgraded LHCb experiment will use a triggerless readout system collecting data at an event rate of 30 MHz. A software-only High Level Trigger will enable unprecedented flexibility for trigger selections. During the first stage (HLT1), a sub-set of the full offline track reconstruction for charged particles is run to select particles of interest. After this first stage, the event rate is reduced by at least a factor 30. Track reconstruction at 30 MHz represents a significant computing challenge, requiring a renovation of current algorithms and the underlying hardware. In this talk, we present the approach of executing the full HLT1 chain on GPUs. This includes decoding the raw data, clustering of hits, pattern recognition, as well as track fitting. We discuss the design of HLT1 algorithms optimized for many-core architectures. Both the computing and physics performance of the full HLT1 chain will be presented.

Collaboration / Activity LHCb
First author Stefania Ricciardi
Email stefania.ricciardi@stfc.ac.uk

Primary author


Presentation Materials