The Persint visualization program for the ATLAS experiment

The Persint program is designed for the three-dimensional representation of objects and for the interfacing and access to a variety of independent applications, in a fully interactive way. Facilities are provided for the spatial navigation and the definition of the visualization properties, in order to interactively set the viewing and viewed points, and to obtain the desired perspective. In parallel, applications may be launched through the use of dedicated interfaces, such as the interactive reconstruction and display of physics events. Recent developments have focalized on the interfacing to the XML ATLAS General Detector Description AGDD, making it a widely used tool for XML developers. The graphics capabilities of this program were exploited in the context of the ATLAS 2002 Muon Testbeam where it was used as an online event display, integrated in the online software framework and participating in the commissioning and debug of the detector system.Comment: 9 pages, 10 figures, proceedings of CHEP200

Application of the ATLAS DAQ and Monitoring System for MDT and RPC Commissioning

The ATLAS DAQ and monitoring software are currently commonly used to test detectors during the commissioning phase. In this paper, their usage in MDT and RPC commissioning is described, both at the surface pre-commissioning and commissioning stations and in the ATLAS pit. Two main components are heavily used for detector tests. The ROD Crate DAQ software is based on the ATLAS Readout application. Based on the plug-in mechanism, it provides a complete environment to interface any kind of detector or trigger electronics to the ATLAS DAQ system. All the possible flavours of this application are used to test and run the MDT and RPC detectors at the pre-commissioning and commissioning sites. Ad-hoc plug-ins have been developed to implement data readout via VME, both with ROD prototypes and emulating final electronics to read out data with temporary solutions, and to provide trigger distribution and busy management in a multi-crate environment. Data driven event building functionality is also used to combine data from different detector technologies. Monitoring software provides a framework for on-line analysis during detector test. Monitoring applications have been developed for noise and cosmic tests and for pulse runs. The PERSINT event display has been interfaced to the monitoring system to provide an on-line event display for cosmic runs in the ATLAS pit

Intensive irradiation studies, monitoring and commissioning data analysis on the ATLAS MDT chambers

The ATLAS MDT chambers have been extensively studied, starting from irradiation test to commissioning activities. First, a detailed description of high rate and high background tests is given. These tests have been carried out on a small ATLAS-like MDT chamber, by the Cosenza and Roma TRE groups. The precision tracking chambers of the muon spectrometer, in fact, have to operate for more than 10 years in the harsh LHC background, due mainly to low energy neutrons and photons. Aging effects, such as the deterioration of the tube themselves can appear and difficulties in pattern recognition and tracking may occur. Moreover an upgrade to Super-LHC is foreseen. Then, there is an accurate description of the MDTGnam package, the official software for the on-line monitoring of MDT performances. When dealing with a complex apparatus, such as the ATLAS experiment, an on-line monitoring system is a fundamental tool. The GNAM project, developed by Cosenza, Pavia, Pisa and Napoli groups, is a monitoring framework to be used by all the ATLAS detectors. The work described in this thesis consisted in writing and optimizing the GNAM C++ code for the MDT detector specific part. The last part is devoted to commissioning data analysis from barrel sector 13. Sector 13 was used as a pilot system to test different detector data taking in their final conditions. Up to November 2006, 13 MDT chambers were installed and their performance monitored both by means of usual noise tests and by cosmic rays penetrating the ATLAS cavern. In addition, the barrel toroid was switched on for the first time at the nominal current. Results from the magnet test are also reported

Hough Transform Track Reconstruction in the Cathode Strip Chambers in ATLAS

The world's largest and highest energy particle accelerator, the Large Hadron Collider (LHC), will collide two highly energetic proton beams in an attempt to discover a wide range of new physics. Among which, the primary ambitions are the discovery of the Higgs boson and suppersymmetric particles. ATLAS, one of its primary particle detectors, was designed as a general-purpose detector covering a broad range of energies and physical processes. A special emphasis on accurate muon tracking has led the ATLAS collaboration to design a stand-alone Muon Spectrometer, an extremely large tracking system extending all the way around the detector. Due to its immense size and range, parts of the spectrometer were designed to withstand a high rate of radiation, sifting the muon signals from the rest of the signals (primarily neutrons and photons). The Cathode Strip Chambers (CSCs) are special multiwire proportional chambers placed in the high $\eta$ region on of the Muon Spectrometer, where flux of background particles is highest. Their purpose is to efficiently filter out the background particle, tracking only the muons traversing it with high degree of accuracy. In order to do that, this special algorithm was designed using a novel modification of the Hough Transform. This thesis will detail the key elements of this algorithm, how it is used for better muon track detection and parameterization, and give a preliminary evaluation of the perform ance of this algorithm

The ATLAS Simulation Infrastructure

The simulation software for the ATLAS Experiment at the Large Hadron Collider is being used for largescale production of events on the LHC Computing Grid. This simulation requires many components, from the generators that simulate particle collisions, through packages simulating the response of the various detectors and triggers. All of these components come together under the ATLAS simulation infrastructure. In this paper, that infrastructure is discussed, including that supporting the detector description, interfacing the event generation, and combining the GEANT4 simulation of the response of the individual detectors. Also described are the tools allowing the software validation, performance testing, and the validation of the simulated output against known physics processes.La lista completa de autores que integran el documento puede verse en el archivo asociado.Facultad de Ciencias Exacta

The ATLAS Simulation Infrastructure

The simulation software for the ATLAS Experiment at the Large Hadron Collider is being used for largescale production of events on the LHC Computing Grid. This simulation requires many components, from the generators that simulate particle collisions, through packages simulating the response of the various detectors and triggers. All of these components come together under the ATLAS simulation infrastructure. In this paper, that infrastructure is discussed, including that supporting the detector description, interfacing the event generation, and combining the GEANT4 simulation of the response of the individual detectors. Also described are the tools allowing the software validation, performance testing, and the validation of the simulated output against known physics processes.La lista completa de autores que integran el documento puede verse en el archivo asociado.Facultad de Ciencias Exacta

Visualization of particle collisions in hadron colliders

In this work we present a visualization system for particle collisions in high- energy physics, which we developed in cooperation with CERN. During the experiments in particle physics a large amount of data is acquired, used for event reconstruction. For better understanding suitable visualization is needed. This poses a big challenge due to large amount of data, especially when we want to achieve real-time interactive functionality. For wider accessibility we decided to implement the visualization in web- based technologies. We developed a visualization system using WebGL, op- timized for fast and efficient use with GPUs. We focused on minimization of draw calls and minimization of data transfer to the the GPU. This proofs as an efficient solution confirmed by performance analysis of the developed system. The system was also tested using the Med3D system, which uses a hybrid rendering mode. This combines rendering through a browser with rendering on a dedicated server

Visualization of particle collisions in hadron colliders

In this work we present a visualization system for particle collisions in high- energy physics, which we developed in cooperation with CERN. During the experiments in particle physics a large amount of data is acquired, used for event reconstruction. For better understanding suitable visualization is needed. This poses a big challenge due to large amount of data, especially when we want to achieve real-time interactive functionality. For wider accessibility we decided to implement the visualization in web- based technologies. We developed a visualization system using WebGL, op- timized for fast and efficient use with GPUs. We focused on minimization of draw calls and minimization of data transfer to the the GPU. This proofs as an efficient solution confirmed by performance analysis of the developed system. The system was also tested using the Med3D system, which uses a hybrid rendering mode. This combines rendering through a browser with rendering on a dedicated server

The ATLAS Simulation Infrastructure

The simulation software for the ATLAS Experiment at the Large Hadron Collider is being used for largescale production of events on the LHC Computing Grid. This simulation requires many components, from the generators that simulate particle collisions, through packages simulating the response of the various detectors and triggers. All of these components come together under the ATLAS simulation infrastructure. In this paper, that infrastructure is discussed, including that supporting the detector description, interfacing the event generation, and combining the GEANT4 simulation of the response of the individual detectors. Also described are the tools allowing the software validation, performance testing, and the validation of the simulated output against known physics processes.La lista completa de autores que integran el documento puede verse en el archivo asociado.Facultad de Ciencias Exacta