arXiv subjects

Thiago R. F. P. Tomei

Publications and source records attributed to Thiago R. F. P. Tomei.

4 recordsLinked to original sources

arXiv2025

CMS Upgrades for the High-Luminosity LHC Era

The High-Luminosity LHC (HL-LHC) era, set to begin in 2029, will provide the general-purpose experiments with an instantaneous luminosity of up to $\mathcal{L} = 7.5 \times 10^{34}$ cm$^{-2}$ s$^{-1}$ from pp collisions at a centre-of-mass energy of 14 TeV. To fully exploit this unprecedented data set, the experimental setups must be upgraded to withstand the challenging conditions of the HL-LHC, including up to 200 simultaneous collisions per bunch crossing and a substantial radiation dose delivered to the detectors. The CMS collaboration is currently undertaking the Phase-2 upgrade, which aims to enhance the detector's capabilities to maintain high performance under these conditions. This upgrade includes significant improvements to the muon spectrometer and barrel calorimeter, a complete replacement of the silicon tracker, endcap calorimeter and beam radiation and luminosity subsystems, the introduction of a new MIP timing detector layer, and a redesigned trigger and data acquisition system. These enhancements will ensure that the CMS experiment can fully profit from on the HL-LHC data, maximising its physics potential and expanding its ability to make the most precise measurements.

hep-ex↗

arXiv2022

The High-Level Trigger for the CMS Phase-2 Upgrade

The High-Luminosity LHC (HL-LHC) will usher in a new era in high-energy physics. The HL-LHC experimental conditions entail an instantaneous luminosity of up to $7.5 \times 10^{34}$ cm$^{-2}$ s$^{-1}$ and up to 200 simultaneous collisions per bunch crossing (pileup). To cope with those conditions, the CMS detector will undergo a series of improvements, in what is known as the Phase-2 upgrade. In particular, the upgrade of the Data Acquisition and of the High-Level Trigger (DAQ-HLT) will have to address a much higher event rate and more complex events. In this paper, we will discuss the aspects of the HLT upgrade, detailing the development of the online reconstruction, the construction, characterisation and timing/rate measurement of a simplified HLT menu, the role of heterogeneous architectures in the HLT and the plan of work and milestones until the beginning of Phase-2.

hep-ex↗

arXiv2020

The CMS Trigger Upgrade for the HL-LHC

The CMS experiment has been designed with a two-level trigger system: the Level-1 Trigger, implemented on custom-designed electronics, and the High Level Trigger, a streamlined version of the CMS offline reconstruction software running on a computer farm. During its second phase the LHC will reach a luminosity of $7.5\times10^{34}\,\textrm{cm}^{-2}\,\textrm{s}^{-1}$ with a pileup of 200 collisions, producing integrated luminosity greater than 3000 fb$^{-1}$ over the full experimental run. To fully exploit the higher luminosity, the CMS experiment will introduce a more advanced Level-1 Trigger and increase the full readout rate from 100 kHz to 750 kHz. CMS is designing an efficient data-processing hardware trigger (Level-1) that will include tracking information and high-granularity calorimeter information. The current conceptual system design is expected to take full advantage of advances in FPGA and link technologies over the coming years, providing a high-performance, low-latency system for large throughput and sophisticated data correlation across diverse sources. The higher luminosity, event complexity and input rate present an unprecedented challenge to the High Level Trigger, that aims to achieve a similar efficiency and rejection factor as today despite the higher pileup and more pure preselection. In this presentation we will discuss the ongoing studies and prospects for the online reconstruction and selection algorithms for the high-luminosity era.

physics.ins-det↗

arXiv2017

Evolution of online algorithms in ATLAS and CMS in Run 2

The Large Hadron Collider has entered a new era in Run 2, with centre-of-mass energy of 13 TeV and instantaneous luminosity reaching $\mathcal{L}_\textrm{inst} = 1.4\times$10$^{34}$ cm$^{-2}$ s$^{-1}$ for pp collisions. In order to cope with those harsher conditions, the ATLAS and CMS collaborations have improved their online selection infrastructure to keep a high efficiency for important physics processes - like W, Z and Higgs bosons in their leptonic and diphoton modes - whilst keeping the size of data stream compatible with the bandwidth and disk resources available. In this note, we describe some of the trigger improvements implemented for Run 2, including algorithms for selection of electrons, photons, muons and hadronic final states.

hep-ex↗