J. Schultes

The power supply system for the ATLAS pixel detector

The innermost part of the ATLAS (A Toroidal LHC Apparatus) experiment at the LHC (Large Hadron Collider), CERN (Conseil Eurpeenne pour la Recherche Nucleaire), will be a pixel detector, which is presently under construction. To operate the approx. 1700 detector modules and their related readout electronics a sophisticated power supply system is required. Its design constraints are the high power density and the sensitivity of the read out chips developed in deep sub-micron technology. A high granularity of the system is desired to allow individual adjustment and to minimize the number of elements out of service. We describe the layout of the full power supply system and concentrate on the components designed in-house: the supply system for the optical link, which offers the possibility of handling a high number of channels at a reasonable price and the remotely-programmable regulator stations, which protect the sensitive front end electronics.

The hardware of the ATLAS Pixel Detector Control System

The innermost part of the ATLAS (A Toroidal LHC ApparatuS) experiment, which is currently under construction at the LHC (Large Hadron Collider), will be a silicon pixel detector comprised of 1744 individual detector modules. To operate these modules, the readout electronics, and other detector components, a complex power supply and control system is necessary. The specific powering and control requirements, as well as the custom made components of our power supply and control systems, are described. These include remotely programmable regulator stations, the power supply system for the optical transceivers, several monitoring units, and the Interlock System. In total, this comprises the Pixel Detector Control System (DCS).

First experiences with the ATLAS pixel detector control system at the combined test beam 2004

Abstract Detector control systems (DCS) include the readout, control and supervision of hardware devices as well as the monitoring of external systems like cooling system and the processing of control data. The implementation of such a system in the final experiment also has to provide the communication with the trigger and data acquisition system (TDAQ). In addition, conditions data which describe the status of the pixel detector modules and their environment must be logged and stored in a common LHC wide database system. At the combined test beam all ATLAS subdetectors were operated together for the first time over a longer period. To ensure the functionality of the pixel detector, a control system was set up. We describe the architecture chosen for the pixel DCS, the interfaces to hardware devices, the interfaces to the users and the performance of our system. The embedding of the DCS in the common infrastructure of the combined test beam and also its communication with surrounding systems will be discussed in some detail.

The control system for the ATLAS pixel detector

A pixel detector is under construction for A Toroidal LHC ApparatuS (ATLAS) experiment, which will utilize the large hadron collider (LHC) at Conseil Europe/spl acute/enne pour la Recherche Nucle/spl acute/aire (CERN). Due to the large number of channels, a data-intensive control system will be required. The choice and design of the requisite hardware for this control system is mainly driven by a high power density and a harsh radiation environment. This includes the development of an interlock system to ensure the safety of the detector, and a special control and supply system for the operation of the optical link connection to the data acquisition (DAQ) readout chain. Given the complexity of the required assembly, a commercial supervisory control and data acquisition (SCADA) system is used. Based on this, we have developed a geographical approach, which matches the different hardware components for the operation of one detector part to uniform software elements. Its tree structure allows clear control of a large amount of information. For the final design, where several SCADA systems are linked, a distributed system is necessary. We have shown this system to work efficiently and will discuss first experiences.

System Tests of the ATLAS Pixel Detector

The innermost part of the ATLAS (A Toroidal LHC ApparatuS)[1] experiment at the LHC (Large Hadron Collider) will be a pixel detector, which is presently under construction. Once installed into the experimental area, access will be extremely limited. To ensure that the integrated detector assembly operates as expected, a fraction of the detector which includes the power supplies and monitoring system, the optical readout, and the pixel modules themselves, has been assembled and operated in a laboratory setting for what we refer to as system tests. Results from these tests are presented.

ATLAS operations in the GridKa T1/T2 Cloud

The ATLAS GridKa cloud consists of the GridKa Tier1 centre and 12 Tier2 sites from five countries associated to it. Over the last years a well defined and tested operation model evolved. Several core cloud services need to be operated and closely monitored: distributed data management, involving data replication, deletion and consistency checks; support for ATLAS production activities, which includes Monte Carlo simulation, reprocessing and pilot factory operation; continuous checks of data availability and performance for user analysis; software installation and database setup. Of crucial importance is good communication between sites, operations team and ATLAS as well as efficient cloud level monitoring tools. The paper gives an overview of the operations model and ATLAS services within the cloud.

Towards the final ATLAS Pixel Detector Control System

The innermost part of the ATLAS experiment is a pixel detector, built by 1744 individual detector modules. To operate the modules, readout electronics, and other detector components, a complex power supply and detector control system (DCS) is necessary. This includes a large number of crates, which house the different hardware components as well as a PC net where the different control projects are running. To test the final detector after its assembly before it is installed in the ATLAS cavern, a large test system has been set up at CERN, which allows to operate ca. 10 % of the detector in parallel. Since autumn 2006 this system is in permanent operation. As nearly everywhere the final control hardware is used, its reliability could be investigated and the performance of the control software could be studied. After an overview on our DCS hardware, we report on the experience with the control software.