The ATLAS High Level Trigger Region of Interest Builder

TL;DR

The paper details the design, testing, and deployment of the ATLAS Region of Interest Builder, a device that interfaces Level 1 trigger data with the high level trigger farm to optimize data processing in the ATLAS detector.

Contribution

It introduces a novel hardware component that efficiently distributes Level 1 trigger data to multiple processors for improved event selection in the ATLAS experiment.

Findings

Successful deployment of the RoIB in the ATLAS detector

Enhanced data processing efficiency for the high level trigger

Reliable operation during data collection periods

Abstract

This article describes the design, testing and production of the ATLAS Region of Interest Builder (RoIB). This device acts as an interface between the Level 1 trigger and the high level trigger (HLT) farm for the ATLAS LHC detector. It distributes all of the level 1 data for a subset of events to a small number of (16 or less) individual commodity processors. These processors in turn provide this information to the HLT. This allows the HLT to use the level 1 information to narrow data requests to areas of the detector where level 1 has identified interesting objects.