arXiv subjects

A. Amorim

Publications and source records attributed to A. Amorim.

95 records · Page 6Linked to original sources

arXiv2003

An on-line Integrated Bookkeeping: electronic run log book and Meta-Data Repository for ATLAS

In the context of the ATLAS experiment there is growing evidence of the importance of different kinds of Meta-data including all the important details of the detector and data acquisition that are vital for the analysis of the acquired data. The Online BookKeeper (OBK) is a component of ATLAS online software that stores all information collected while running the experiment, including the Meta-data associated with the event acquisition, triggering and storage. The facilities for acquisition of control data within the on-line software framework, together with a full functional Web interface, make the OBK a powerful tool containing all information needed for event analysis, including an electronic log book. In this paper we explain how OBK plays a role as one of the main collectors and managers of Meta-data produced on-line, and we'll also focus on the Web facilities already available. The usage of the web interface as an electronic run logbook is also explained, together with the future extensions. We describe the technology used in OBK development and how we arrived at the present level explaining the previous experience with various DBMS technologies. The extensive performance evaluations that have been performed and the usage in the production environment of the ATLAS test beams are also analysed.

cs.DB↗

arXiv2003

Online Monitoring software framework in the ATLAS experiment

A fast, efficient and comprehensive monitoring system is a vital part of any HEP experiment. This paper describes the software framework that will be used during ATLAS data taking to monitor the state of the data acquisition and the quality of physics data in the experiment. The framework has been implemented by the Online Software group of the ATLAS Trigger&Data Acquisition (TDAQ) project and has already been used for several years in the ATLAS test beams at CERN. The inter-process communication in the framework is implemented via CORBA, which provides portability between different operating systems and programming languages. This paper will describe the design and the most important aspects of the online monitoring framework implementation. It will also show some test results, which indicate the performance and scalability of the current implementation.

hep-ex↗

arXiv2003

Verification and Diagnostics Framework in ATLAS Trigger/DAQ

Trigger and data acquisition (TDAQ) systems for modern HEP experiments are composed of thousands of hardware and software components depending on each other in a very complex manner. Typically, such systems are operated by non-expert shift operators, which are not aware of system functionality details. It is therefore necessary to help the operator to control the system and to minimize system down-time by providing knowledge-based facilities for automatic testing and verification of system components and also for error diagnostics and recovery. For this purpose, a verification and diagnostic framework was developed in the scope of ATLAS TDAQ. The verification functionality of the framework allows developers to configure simple low-level tests for any component in a TDAQ configuration. The test can be configured as one or more processes running on different hosts. The framework organizes tests in sequences, using knowledge about components hierarchy and dependencies, and allowing the operator to verify the functionality of any subset of the system. The diagnostics functionality includes the possibility to analyze the test results and diagnose detected errors, e.g. by starting additional tests and understanding reasons of failures. A conclusion about system functionality, error diagnosis and recovery advice are presented to the operator in a GUI. The current implementation uses the CLIPS expert system shell for knowledge representation and reasoning.

hep-ex↗

arXiv1998

New CP-violating parameters in cascade decays

We consider decay chains of the type P -> M + ... -> f + ..., where M is a neutral meson that may mix with its antiparticle Mbar, before decaying into the final state f. P may be either a heavier neutral meson or a charged meson. We perform a rephasing-invariant analysis of the quantities that show up in such cascade decays. If the decay P -> M + ... (or the decay P -> Mbar + ...) is forbidden, we find the usual lambda_f parameters describing the interference between the mixing of a neutral meson system and the decay from that system into the final state f. However, when both the P -> M + ... and P -> Mbar + ... decays are allowed, we find a new class of rephasing-invariant parameters, xi_i, that measure the interference between the mixing of a neutral meson system and the decay from the initial state *into that system*. We show that the quantities lambda_f and xi_i are necessary and sufficient to describe all the interference effects present in the most general cascade decay. We discuss the various cascade decays in turn, highlighting the special features of each one.

hep-ph↗

arXiv1997

Relativistic deuteron structure function at large Q^2

The deuteron deep inelastic unpolarized structure function F_2^D is calculated using the Wilson operator product expansion method. The long distance behaviour, related to the deuteron bound state properties, is evaluated using the Bethe-Salpeter equation with one particle on mass shell. The calculation of the ratio F_2^D/F_2^N is compared with other convolution models showing important deviations in the region of large x. The implications in the evaluation of the neutron structure function from combined data on deuterons and protons are discussed.

nucl-th↗