The ATLAS Tile Calorimeter Tools for Data Quality Assessment

The ATLAS Tile Calorimeter (TileCal) is the central part of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. The readout is segmented into nearly 10000 channels that are calibrated by means of Cesium source, laser, charge injection, and integratorbased systems. The data quality (DQ) relies on extensive monitoring of both collision and calibration data. Automated checks are performed on a set of pre-defined histograms and results are summarized in dedicated web pages. A set of tools is then used by the operators for further inspection of the acquired data with the goal of spotting the origins of problems or other irregularities. Consequently, the TileCal conditions data (calibration constants, channel statuses etc) are updated in databases that are used for the data-reprocessing, or serve as an important input for the maintenance works during the shutdown periods. This talk reviews the software tools used for the DQ monitoring with emphasis on recent developments aiming to integrate all tools into a single platform.

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Search for squark production in events with jets, hadronically decaying tau leptons and missing transverse energy at s=1.96 TeV

Physics Letters B ◽

10.1016/j.physletb.2009.08.002 ◽

2009 ◽

Vol 680 (1) ◽

pp. 24-33 ◽

Cited By ~ 7

Author(s):

V.M. Abazov ◽

B. Abbott ◽

M. Abolins ◽

B.S. Acharya ◽

M. Adams ◽

...

Keyword(s):

Transverse Energy ◽

Tau Leptons ◽

Missing Transverse Energy

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ATLAS Tile Calorimeter calibration and monitoring systems

EPJ Web of Conferences ◽

10.1051/epjconf/201817001003 ◽

2018 ◽

Vol 170 ◽

pp. 01003

Author(s):

Arely Cortés-González

Keyword(s):

Data Quality ◽

Transverse Energy ◽

Charged Particles ◽

Outer Part ◽

Steel Plates ◽

Hadronic Decays ◽

Readout System ◽

Scintillation Light ◽

And Performance ◽

Essential Contribution

The ATLAS Tile Calorimeter is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes, located in the outer part of the calorimeter. Neutral particles may also produce a signal after interacting with the material and producing charged particles. The readout is segmented into about 5000 cells, each of them being read out by two photomultipliers in parallel. To calibrate and monitor the stability and performance of each part of the readout chain during the data taking, a set of calibration systems is used. This comprises Cesium radioactive sources, Laser, charge injection elements and an integrator based readout system. Information from all systems allows to monitor and equalise the calorimeter response at each stage of the signal production, from scintillation light to digitisation. Calibration runs are monitored from a data quality perspective and used as a cross-check for physics runs. The data quality efficiency achieved during 2016 was 98.9%. These calibration and stability of the calorimeter reported here show that the TileCal performance is within the design requirements and has given essential contribution to reconstructed objects and physics results.

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Tile-in-One: an integrated system for data quality and condition assessment for the ATLAS Tile Calorimeter

EPJ Web of Conferences ◽

10.1051/epjconf/202024501010 ◽

2020 ◽

Vol 245 ◽

pp. 01010

Author(s):

Yuri Smirnov ◽

Juraj Smieško

Keyword(s):

Data Quality ◽

Web Application ◽

Transverse Energy ◽

Virtual Machines ◽

Condition Assessment ◽

Integrated System ◽

Missing Transverse Energy ◽

Common System ◽

Authentication And Authorization ◽

The Stability

The Tile Calorimeter (TileCal) is a crucial part of the ATLAS detector, which jointly with other calorimeters reconstructs hadrons, jets, tau-particles, missing transverse energy and assists in muon identification. It consists of alternating steel absorber layers and active scintillating tiles and covers the region |η| < 1.7. The TileCal is regularly monitored by several systems, which were developed mainly during the commissioning of the detector in order to meet distinct requirements. Any problem is reported and immediately investigated, which results in data quality efficiency very close to 100%, as achieved over the last few years. Although the TileCal tools are maintained, the underlying technologies are becoming gradually outdated. The Tile-in-One web platform strives to integrate all data quality and condition assessment TileCal tools into one common system. This system is implemented as a web application with the main machine being the gateway for so-called plugins. These are standalone small web application hosted on a single virtual machine. The plugins are separated into virtual machines due to the requirement of different data sources and to avoid interference in order to increase the stability of the platform. The main server is responsible for the authentication and authorization of the users, as well as the management of the plugins. Currently the platform consists of 13 plugins in various stages of development. The implementation details of the Tile-in-One web system and selected plugins are presented in this document.

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The CMS Particle Flow Algorithm

EPJ Web of Conferences ◽

10.1051/epjconf/201819102016 ◽

2018 ◽

Vol 191 ◽

pp. 02016

Author(s):

Milos Dordevic

Keyword(s):

Transverse Energy ◽

Hadron Collider ◽

Particle Flow ◽

Tau Leptons ◽

Missing Transverse Energy ◽

Final State ◽

Event Reconstruction ◽

Flow Algorithm ◽

And Performance ◽

Traditional Approaches

The event reconstruction at the Compact Muon Solenoid (CMS) experiment at the CERN Large Hadron Collider (LHC) is predominantly based on the Particle Flow algorithm. This algorithm for a global event description uses the information from all subdetector systems, unlike the previous, traditional approaches that were focused on the localized information in each subdetector. These traditional methods use the raw information (tracks, hits), while the Particle Flow algorithm completely reconstructs the event by identifying and reconstructing the comprehensive list of final-state particles (photons, electrons, muons, charged and neutral hadrons), resulting in superior reconstruction of jets, missing transverse energy, tau leptons, electrons and muons. This approach also allows for efficient identification and mitigation of the pileup effect. The concept and performance of the Particle Flow algorithm, together with the prospects for its development in the context of the upgraded CMS detector, are presented in this overview.

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