A.G. Mello
A5002311371- Particle Detector Development and Performance
- Particle physics theoretical and experimental studies
- Advanced Data Storage Technologies
- Distributed and Parallel Computing Systems
- Radiation Detection and Scintillator Technologies
- Neutrino Physics Research
- Particle Accelerators and Free-Electron Lasers
- High-Energy Particle Collisions Research
- History and Developments in Astronomy
- Astrophysics and Cosmic Phenomena
- Energy Efficiency in Computing
- Parallel Computing and Optimization Techniques
- Astronomy and Astrophysical Research
- Botanical Research and Applications
- Experimental Learning in Engineering
- Plant Diversity and Evolution
- Superconducting Materials and Applications
- Plant and animal studies
- Particle accelerators and beam dynamics
- Methane Hydrates and Related Phenomena
Universidade Federal do Rio de Janeiro
2003-2024
Office National d'Études et de Recherches Aérospatiales
2006
Pontifícia Universidade Católica do Rio Grande do Sul
2006
European Organization for Nuclear Research
2004-2005
Centre de physique des particules de Marseille
2005
The ATLAS High Level Trigger's (HLT) primary function of event selection will be accomplished with a Level-2 trigger farm and an filter (EF) farm, both running software components developed in the offline reconstruction framework. While this approach provides unified framework for selection, it poses strict requirements on critical trigger. A decision must typically within 10 ms multiple processing concurrent threads. To address these constraints, prototypes have been that incorporate...
Following rigorous software design and analysis methods, an object-based architecture has been developed to derive the second- third-level trigger decisions for future ATLAS detector at LHC. The functional components within this system responsible generating elements of are algorithms running architecture. Relevant aspects reviewed along with concrete examples specific their performance in "vertical" slices various physics selection strategies.
The ATLAS trigger reduces the rate of interesting events to be recorded for off-line analysis in three successive levels from 40 MHz /spl sim/100 kHz, sim/2 kHz and sim/200 Hz. high level triggers data acquisition system are designed profit commodity computing networking components achieve required performance. In this paper, we discuss flow aspects design second (LVL2) present results performance measurements.
The Event Filter (EF) selection stage is a fundamental component of the ATLAS Trigger and Data Acquisition architecture. Its primary function reduction data flow rate to values acceptable by mass storage operations subsequent offline reconstruction analysis steps. computing instrument EF organized as set independent subfarms, each connected one output Builder (EB) switch fabric. Each subfarm comprises number processors analyzing several complete events in parallel. This paper describes...
The ATLAS experiment at the Large Hadron Collider (LHC) will face challenge of efficiently selecting interesting candidate events in pp collisions 14 TeV center-of-mass energy, whilst rejecting enormous number background events. High-Level Trigger (HLT=second level trigger and Event Filter), which is a software based need to reduce level-1 output rate ap75 kHz ap200 Hz written out mass storage. In this talk an overview current physics system performance HLT selection for electrons photons...
The ATLAS combined test beam in the second half of 2004 saw first deployment High-Level Trigger (HLT). next steps are on pre-series farms experimental area during 2005, commissioning and cosmics tests with full detector 2006 collisions 2007. This paper reviews experience gained beam, describes current status discusses further enhancements to be made. We address issues related dataflow, integration selection algorithms, testing, software distribution, installation improvements.
During the runtime of any experiment, a central monitoring system that detects problems as soon they appear has an essential role. In large like ATLAS, online data acquisition is distributed across nodes farms, each them running several processes analyse fraction events. this architecture, it necessary to have process collects all from different nodes, produces full statistics histograms and analyses them. paper we present design such system, called gatherer. It allows collect object,...
To cope with the 40 MHz event production rate of LHC, trigger ATLAS experiment selects events in three sequential steps increasing complexity and accuracy whose final results are close to offline reconstruction. The Level-1, implemented custom hardware, identifies physics objects within Regions Interests operates a first reduction 75 kHz. higher levels, Level-2 Level-3, provide software based selection which further reduces about 100 Hz. This paper presents algorithm (/spl mu/Fast) employed...
ATLAS is one of the four LHC experiments that will start data taking in 2007, designed to cover a wide range physics topics. The trigger system has cope with rate 40 MHz and 23 interactions per bunch crossing. It divided three different levels. first (hardware based) provides signature confirmed by following levels (software running sequence algorithms validating signal step step, looking only region space indicated level (seeding). In this presentation, performance these sequences run at...
The ATLAS combined test beam in the second half of 2004 saw first deployment high-level triggers (HLT). next steps are on pre-series farms experimental area during 2005, commissioning and cosmics tests 2006 collisions 2007. This paper reviews experience gained beam, describes current status discusses further enhancements to be made. We address issues related dataflow, selection algorithms, testing, software distribution, installation improvements
The ATLAS experiment at the Large Hadron Collider (LHC) will face challenge of efficiently selecting interesting candidate events in pp collisions 14 TeV center mass energy, while rejecting enormous number background events, stemming from an interaction rate up to 10/sup 9/ Hz. Level1 trigger reduce this around /spl Oscr/(100kHz). Subsequently, high level (HLT), which is comprised Second Level and Event Filter, need further by a factor Oscr/(10/sup 3/). HLT selection software based be...
ATLAS is one of the four major Large Hadron Collider (LHC) experiments that will start data taking in 2007. It designed to cover a wide range physics topics. The trigger system has be able reduce an initial 40 MHz event rate, corresponding average 23 proton-proton inelastic interactions per every 25 ns bunch crossing, 200 Hz admissible by Data Acquisition System. divided three different levels. first provides signal describing signature using dedicated custom hardware. This must confirmed...
The ATLAS trigger reduces the rate of interesting events to be recorded for off-line analysis in three successive levels from 40 MHz about 100 kHz, 2 kHz and 200 Hz. High Level Triggers Data Acquisition System are designed profit commodity computing networking components achieve required performance. We discuss Flow aspects design Second Trigger (LVL2) present results performance measurements.
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The trigger system of the ATLAS experiment at LHC aims a high selectivity in order to keep full physics potential while reducing 40 MHz initial event rate imposed by bunch crossing down /spl sim/100 Hz, as required data acquisition system. Algorithms working final stage environment (Event Filter) are implemented run both "wrapped" mode (reconstructing tracks entire Muon Spectrometer) and "seeded" (according dedicated strategy that performs pattern recognition only regions detector where...