Run 2 Upgrades to the CMS Level-1 Calorimeter Trigger

TL;DR

This paper describes the two-stage upgrade of the CMS Level-1 calorimeter trigger, enhancing its algorithms, resolution, and processing capabilities to cope with increased LHC luminosity and pile-up.

Contribution

It introduces new algorithms with pile-up corrections, higher granularity inputs, and a time-multiplexed approach, along with hardware upgrades using Xilinx Virtex-7 AMC cards.

Findings

Improved trigger performance under higher pile-up conditions

Enhanced energy and position resolution with new algorithms

Successful implementation of hardware upgrades for data processing

Abstract

The CMS Level-1 calorimeter trigger is being upgraded in two stages to maintain performance as the LHC increases pile-up and instantaneous luminosity in its second run. In the first stage, improved algorithms including event-by-event pile-up corrections are used. New algorithms for heavy ion running have also been developed. In the second stage, higher granularity inputs and a time-multiplexed approach allow for improved position and energy resolution. Data processing in both stages of the upgrade is performed with new, Xilinx Virtex-7 based AMC cards.