Web System for Data Quality Assessment of Tile Calorimeter During the ATLAS Operation

TileCal is the barrel hadronic calorimeter of the ATLAS experiment and has ~10 000 electronic channels. Supervising the detector behavior is a very important task to ensure proper operation. Collaborators perform analyzes over reconstructed data of calibration runs in order to give detailed considerations about failures and to assert the equipment status. Then, the data quality responsible provides the list of problematic channels that should not be considered for physics analysis. Since the commissioning period, our group has developed seven web systems that guide the collaborators through the data quality assessment task. Each system covers a part of the job, providing information on the latest runs, displaying status from the automatic monitoring framework, giving details about power supplies operation, presenting the generated plots and storing the validation outcomes, assisting to write logbook entries, creating and submitting the bad channels list to the conditions database and publishing the equipment performance history. Due to the beginning of the operation, runs are acquired more often. The increasing amount of data represents a new challenge to the systems. Until now, over ninety million plots are stored in the databases, affecting the performance of the systems. Thus, an optimized data model was designed to reduce the number of needed queries. The web systems were reassembled in a unique system to provide an integra ted view of the validating process. The server load was minimized by using asynchronous requests from the browser. This article describes the new approach and reports the performance improvement.

Glance Information System for ATLAS Management

ATLAS Experiment is an international collaboration where more than 37 countries, 172 institutes and laboratories, 2900 physicists, engineers, and computer scientists plus 700 students participate. The management of this teamwork involves several aspects such as institute contribution, employment records, members' appointment, authors' list, preparation and publication of papers and speakers nomination. Previously, most of the information was accessible by a limited group of people and the system used was not designed to handle new requirements easily. Moreover, developers had to face problems such as different terminology, diverse data modeling, heterogeneous databases and unlike users needs. Besides that, the maintenance has to be an easy task considering the long lifetime experiment and professionals turnover. The Glance system, a generic mechanism for accessing any database, acts as an intermediate layer isolating the user from the particularities of each database. It retrieves, inserts and updates the database independently of its technology and modeling. Relying on Glance, a group of systems were built to support the ATLAS management aspects: ATLAS Membership, ATLAS Appointments, ATLAS Speakers, ATLAS Analysis Follow-Up and ATLAS Conference Notes. This paper presents the overview of the Glance information system framework and describes the privilege mechanism developed to grant different level of access for each member and system. The performance of such approach will also be explained, showing the resultant decentralization of the ATLAS administrative activities and its benefits for the whole collaboration

ATLAS

% ATLAS \\ \\ ATLAS is a general-purpose experiment for recording proton-proton collisions at LHC. The ATLAS collaboration consists of 144 participating institutions (June 1998) with more than 1750~physicists and engineers (700 from non-Member States). The detector design has been optimized to cover the largest possible range of LHC physics: searches for Higgs bosons and alternative schemes for the spontaneous symmetry-breaking mechanism; searches for supersymmetric particles, new gauge bosons, leptoquarks, and quark and lepton compositeness indicating extensions to the Standard Model and new physics beyond it; studies of the origin of CP violation via high-precision measurements of CP-violating B-decays; high-precision measurements of the third quark family such as the top-quark mass and decay properties, rare decays of B-hadrons, spectroscopy of rare B-hadrons, and $B ^0 _{s}$-mixing. \\ \\The ATLAS dectector, shown in the Figure includes an inner tracking detector inside a 2~T~solenoid providing an axial field, electromagnetic and hadronic calorimeters outside the solenoid and in the forward regions, and barrel and end-cap air-core-toroid muon spectrometers. The precision measurements for photons, electrons, muons and hadrons, and identification of photons, electrons, muons, $\tau$-leptons and b-quark jets are performed over $| \eta |$ < 2.5. The complete hadronic energy measurement extends over $| \eta |$ < 4.7. \\ \\The inner tracking detector consists of straw drift tubes interleaved with transition radiators for robust pattern recognition and electron identification, and several layers of semiconductor strip and pixel detectors providing high-precision space points. \\ \\The e.m. calorimeter is a lead-Liquid Argon sampling calorimeter with an integrated preshower detector and a presampler layer immediately behind the cryostat wall for energy recovery. The end-cap hadronic calorimeters also use Liquid Argon technology, with copper absorber plates. The end-cap cryostats house the e.m., hadronic and forward calorimeters (tungsten-Liquid Argon sampling). The barrel hadronic calorimeter is an iron-scintillating tile sampling calorimeter with longitudinal tile geometry. \\ \\Air-core toroids are used for the muon spectrometer. Eight superconducting coils with warm voussoirs are used in the barrel region complemented with superconducting end-cap toroids in the forward regions. The toroids will be instrumented with Monitored Drift Tubes (Cathode Strip Chambers at large rapidity where there are high radiation levels). The muon trigger and second coordinate measurement for muon tracks are provide