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M. Plesko

Publications and source records attributed to M. Plesko.

6 recordsLinked to original sources

The Forward GEM Tracker of STAR at RHIC

The STAR experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) is in the process of designing and constructing a forward tracking system based on triple GEM technology. This upgrade is necessary to give STAR the capability to reconstruct and identify the charge sign of W bosons over an extended rapidity range through their leptonic decay mode into an electron (positron) and a neutrino. This will allow a detailed study of the flavor-separated spin structure of the proton in polarized p + p collisions uniquely available at RHIC. The Forward GEM Tracker FGT will consist of six triple GEM disks with an outer radius of ~39 cm and an inner radius of ~10.5 cm, arranged along the beam pipe, covering the pseudo-rapidity range from 1.0 to 2.0 over a wide range of collision vertices. The GEM foils will be produced by Tech-Etch, Inc. Beam tests with test detectors using 10 cm x 10 cm Tech-Etch GEM foils and a two dimensional orthogonal strip readout have demonstrated a spatial resolution of 70 um or better and high efficiency.

physics.ins-det

The Object Oriented Approach to Machine Physics Calculations with Java Technology

At least as much time is spent solving problems addressed by application support as with actual interaction with the control system, if it is not factored into separate libraries but is coded by each programmer time and time again. Our Java libraries, called Abeans, address these issues in a communication platform independent way. Abeans perform connection management, error and timeout handling, logging, reporting, authentication, resource initialization and destruction, policy and configuration management, etc. Abeans also hide the communication details from the programmer and combine with CosyBeans, our GUI Java components, to form SCADA-like control panels. They are successfully used in such different environments such as a synchrotron light source (ANKA, Germany), an e-p collider complex (DESY, Germany), proton cyclotron (Riken, Japan) and a radio telescope (ESO, Germany). The Java library DataBush has a similar function for machine physics programs. The object oriented design of the library gives programmer intuitive access to devices and elements relevant to machine physics. For example, a non-visual Java Bean represents a magnet with its relevant machine physics parameters. Access to the control system is provided transparently with Abeans in communication platform independent way. Error diagnostics and event handling is part of the Abeans and DataBush framework. By default DataBush receives new data and performs linear optics calculation of machine functions with a one second heartbeat.

physics.acc-ph

A Guerilla Approach to Control System Development

We present our experiences in managing the development cycles of the control systems for ANKA and the ALMA Common Software. Our team consists practically only of undergraduate students. Stimulating and rewarding the students with cutting-edge technologies and travel to conferences like this and installation fieldwork are an important positive factor in raising their motivation. However, building any system with a group of inexperienced students is quite a challenging task. Many problems occur with planning deadlines and missing them, organizing and managing development, sources, and documentation and also when dealing with conventional program management rules. To cope with them, we use many tools: CVS for versioning and source archiving, Bugzilla for keeping our bugs in order, a to-do list for managing tasks, an activity log and also many other programs and scripts, some found on the Internet and some made by ourselves. In the end, we had to become organized like a professional company. Documentation and demos can be found on our homepage: http://kgb.ijs.si/KGB. Because of powerful intranet/web front-ends of all those tools, our Internet pages are the central resource for developers, who work mostly off-site.

physics.acc-ph

Experiences with advanced CORBA services

The Common Object Request Broker Architecture (CORBA) is successfully used in many control systems (CS) for data transfer and device modeling. Communication rates below 1 millisecond, high reliability, scalability, language independence and other features make it very attractive. For common types of applications like error logging, alarm messaging or slow monitoring, one can benefit from standard CORBA services that are implemented by third parties and save tremendous amount of developing time. We have started using few CORBA services on our previous CORBA-based control system for the light source ANKA [1] and use now several CORBA services for the ALMA Common Software (ACS) [2], the core of the control system of the Atacama Large Millimeter Array. Our experiences with the interface repository (IFR), the implementation repository, the naming service, the property service, telecom log service and the notify service from different vendors are presented. Performance and scalability benchmarks have been performed.

cs.PF

New Abeans for TINE Java Control Applications

Abeans [1] (wide-interface accelerator Java beans developed at JSI) have in the past been used with great success in control applications at ANKA and ESO and on test cases at the SLS and Riken. At DESY, TINE [2] is used as the principal control system for HERA as well as the intercommunication protocol among the HERA experiments. To date, most TINE-based client-side applications have been written using ACOP [3] (a narrow-interface accelerator component) in Visual Basic (VB), which has provided a remarkably powerful developing environment for generating professional control applications. Currently, however, VB control applications can only run on Windows-based desktop machines and consoles. As it is often desirable to provide certain control applications on non-Windows platforms (or indeed over the Web), we have created an equally powerful developing environment based on Java and the next release of Abeans, where an ACOP-like narrow-interface bean has been developed. Like ACOP, the Abean itself accepts plugs from various communication protocols, but was brought to fruition at DESY using the TINE Java class. Details concerning matching Abeans and TINE, as well as the pros and cons of wide versus narrow interfaces will be presented below. Several applications will also presented along with the results of benchmarking against similar VB applications.

physics.acc-ph

Common Software for the ALMA project

The Atacama Large Millimeter Array (ALMA) is a joint project between astronomical organizations in Europe, USA and Japan. ALMA will consist of at least 64 12-meter antennas operating in the millimeter and sub-millimeter wavelength range, with baselines up to 10 km. It will be located at an altitude above 5000m in the Chilean Atacama desert[1]. The ALMA Common Software (ACS) provides a software infrastructure common to all partners and consists of a documented collection of common patterns in control systems and of components, which implement those patterns. The heart of ACS is an object model of controlled devices, called Distributed Objects (DOs), implemented as CORBA network objects. Components such as antenna mount, power supply, etc. are defined by means of DOs. A code generator creates Java Bean components for each DO. Programmers can write Java client applications by connecting those Beans with data-manipulation and visualization Beans using commercial visual development tools or programmatically. ACS is based on the experience accumulated with similar projects in the astronomical and particle accelerator contexts, reusing and extending concepts and components. Although designed for ALMA, ACS has the potential for being used in other new control systems and other distributed software projects, since it implements proven design patterns using state of the art, stable and reliable technology.

physics.acc-ph