The ALICE Detector Control System Chochula, P; Jirden, L; Augustinus, A ...
IEEE transactions on nuclear science,
04/2010, Letnik:
57, Številka:
2
Journal Article
Recenzirano
Odprti dostop
ALICE is one of the six currently installed experiments at the Large Hadron Collider (LHC) at CERN (Geneva, Switzerland). The experiment saw its first particles during the commissioning of the LHC ...accelerator in 2008 and is now preparing for the first physics runs foreseen for the autumn of 2009. The experiment is composed of a large number of sub-detectors, each with up to 15 different subsystems that need to be controlled and operated in an efficient and reliable way. For this purpose, a Detector Control System (DCS) has been developed based on latest technologies and using new and innovative approaches. The DCS system has been used with success during the commissioning of the individual detectors as well as during the cosmic runs and the LHC injection tests that were carried out in 2008. This paper gives an overview of the control system and it describes the architecture, the tools and the components that have been used to build it. Examples of technical implementations are given and new trends and techniques used in the system are highlighted.
ALICE Controls data produced by commercial SCADA system WINCCOA is stored in ORACLE database on the private experiment network. The SCADA system allows for basic access and processing of the ...historical data. More advanced analysis requires tools like ROOT and needs therefore a separate access method to the archives. The present scenario expects that detector experts create simple WINCCOA scripts, which retrieves and stores data in a form usable for further studies. This relatively simple procedure generates a lot of administrative overhead – users have to request the data, experts needed to run the script, the results have to be exported outside of the experiment network. The new mechanism profits from database replica, which is running on the CERN campus network. Access to this database is not restricted and there is no risk of generating a heavy load affecting the operation of the experiment. The developed tools presented in this paper allow for access to this data. The users can use web-based tools to generate the requests, consisting of the data identifiers and period of time of interest. The administrators maintain full control over the data – an authorization and authentication mechanism helps to assign privileges to selected users and restrict access to certain groups of data. Advanced caching mechanism allows the user to profit from the presence of already processed data sets. This feature significantly reduces the time required for debugging as the retrieval of raw data can last tens of minutes. A highly configurable client allows for information retrieval bypassing the interactive interface. This method is for example used by ALICE Offline to extract operational conditions after a run is completed. Last but not least, the software can be easily adopted to any underlying database structure and is therefore not limited to WINCCOA.
ALICE (A Large Ion Collider Experiment) is one of the big LHC (Large Hadron Collider) experiments at CERN in Geneve, Switzerland. The experiment is composed of 18 sub-detectors controlled by an ...integrated Detector Control System (DCS) that is implemented using the commercial SCADA package PVSSII. The DCS includes over 1200 network devices, over 1,000,000 monitored parameters and numerous custom made software components that are prepared by over 100 developers from all around the world. This complex system is controlled by a single operator via a central user interface. One of his/her main tasks is the recovery of anomalies and errors that may occur during operation. Therefore, clear, complete and easily accessible documentation is essential to guide the shifter through the expert interfaces of different subsystems. This paper describes the idea of the management of the operational documentation in ALICE using a generic repository that is built on a relational database and is integrated with the control system. The experience gained and the conclusions drawn from the project are also presented.
The ALICE Silicon Pixel Detector: System, components and test procedures Riedler, P.; Anelli, G.; Antinori, F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2006, Letnik:
568, Številka:
1
Journal Article
Recenzirano
The ALICE Silicon Pixel Detector consists of two barrel layers of hybrid silicon pixel detectors. In total
9.8
×
10
6
pixel cells with
50
μ
m
×
425
μ
m
will provide precision tracking information in ...the high multiplicity environment expected in heavy ion collisions. This paper gives an overview of the system, its components and the test procedures that have been developed.
Recent test results of the ALICE silicon pixel detector Riedler, P.; Anelli, G.; Antinori, F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2005, Letnik:
549, Številka:
1
Journal Article
Recenzirano
The ALICE SPD (Silicon Pixel Detector) forms the two innermost layers of the Inner Tracking System (ITS) of the ALICE experiment at LHC. After several years of development the production of the ...modules is starting. The present article provides an overview of the different elements that will be used in the SPD with special emphasis given to testing of wafers and bump-bonded ladders.
The two innermost layers of the ALICE inner tracking system are instrumented with silicon pixel detectors. Single chip assembly prototypes of the ALICE pixels have been tested in high energy particle ...beams at the CERN SPS. Detection efficiency and spatial precision have been studied as a function of the threshold and the track incidence angle. The experimental method, data analysis and main results are presented.
First results from the ALICE silicon pixel detector prototype Riedler, P; Anelli, G; Antinori, F ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2003, Letnik:
501, Številka:
1
Journal Article
Recenzirano
System prototyping of the ALICE silicon pixel detector (SPD) is well underway. The ALICE SPD consists of two barrel layers with 9.83 million channels in total. These are read out by the ALICE1LHCb ...pixel chip, which has been developed in a commercial
0.25
μm
process with radiation hardening by design layout. The readout chip contains 8192 pixel cells each with a fast analog preamplifier and shaper followed by a discriminator and digital delay lines. Test results show a pixel cell noise of about 110 electrons rms and a mean minimum threshold of about 1000 electrons rms before threshold fine tuning. Several readout chips have been flip-chip bonded to detectors using two different bump-bonding techniques (solder, indium). Results of radioactive source measurements of these assemblies are presented for
90
Sr
and
55
Fe
sources. Several chip-detector assemblies have been tested in a
150
GeV/
c
pion beam at CERN where an online efficiency of about 99% across a wide range of detector bias and threshold settings was observed. All preliminary investigations confirm the functionality of the chip and the chip-detector assemblies for the ALICE experiment.
The Silicon Pixel Detector (SPD) forms the two innermost layers of the ALICE Inner Tracking System (ITS). The detector includes 1200 readout ASICs, each containing 8192 pixel cells, bump-bonded to Si ...sensor elements. The thickness of the readout chip and the sensor element is 150
μm and 200
μm, respectively. Low-mass solutions are implemented for the bus and the mechanical support. In this contribution, we describe the basic module (half-stave) of the two SPD layers and we give an overview of its assembly procedure.
Test beam performance of the ALICE silicon pixel detector NILSSON, P; ANELLI, G; ANTINORI, F ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2004, Letnik:
535, Številka:
1-2
Journal Article
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