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1.
Data quality monitoring (DQM) plays an important role in data taking at the BESⅢ experiments. DQM is used to monitor detector status and data quality. A DQM framework (DQMF) has been developed to make it possible to reuse the BESⅢ offline reconstruction system in the online environment. In this framework, the DQMF can also simulate a virtual data taking environment, transfer events to the event display, publish histograms to a histogram presenter in a fixed interval, and dump histograms into a ROOT file. The DQMF has been stably running throughout BESⅢ data taking.  相似文献   

2.
The BES detector has operated for about 12 years,and the BES offline data analysis environment also has been developed and upgraded along with developments of the BES hardware and software.The BESⅢ software system will operate for many years.Thus they should meet developments of the new technology in software,It should be highly flexible,Powerful,stable and easy for maintenance.And following points should be taken into account:1) To benefit the collaboration and make better exchanges with the international HEP experiments this system shoule be set up by adopting or referring the newest technology in the software from advanced experiments in the world.2).It should support hundreds of the existing BES software packages and serve for both old experts who familiar with BESII software and computing environment and new members who is going to benefit from the new system.3).The most BESII existing packages will be modified or re-designed according to the hardware changes.  相似文献   

3.
Since 1998,the ALICE experiment and the CERN/IT division have jointly executed several large-scale high throughput distributed computing exercises:the ALICE data challenges.The goals of these regular exercises are to test hardware and software components of the data acqusition and computing systems in realistic conditions and to execute an early integration of the overall ALICE computing infrastructure.This paper reports on the third ALICE Data Challenge (ADC III) that has been performed at CERN from January to March 2001.The data used during the ADC Ⅲ are simulated physics raw data of the ALICE TPC,produced with the ALICE simulation program AliRoot.The data acquisition was based on the ALICE online framework called the ALICE Data Acquisition Test Environment (DATE) system.The data after event building,were then formatted with the ROOT I/O package and a data catalogue based on MySQl was established.The Mass Storage System used during ADC III is CASTOR.Different software tools have been used to monitor the performances,DATE has demonstrated performances of more than 500 MByte/s.An aggregate data throughput of 85 MByte/s was sutained in CASTOR over several days.The total collected data amounts to 100 TBytes in 100.00 files.  相似文献   

4.
To monitor the integral dose deposited in the BESⅢ electromagnetic calorimeter whose performance degrades due to exposure to the BEPC Ⅱ background, a 400 nm IMPL RadFET dosimeter-based integral dose online monitor system is built, After calibration with the ^60Co source and verification with TLD in the pulse radiation fields, an experiment was arranged to measure the BEPC Ⅱ background online. The results are presented.  相似文献   

5.
The installation of the BESⅢ RPC system has been completed. Cosmic ray test results show that they perform very well in streamer mode and meet the BESⅢ requirements. We have tested several RPCs in the avalanche mode with the addition of extra SF6 in the gas mixture. We find an efficiency plateau that reaches ~95%, and a time resolution of 1.8 ns. This demonstrates that the BESⅢ-type RPC can work in the avalanche mode as well.  相似文献   

6.
The current computing environment of our Computing Center in IHEP uses a SAS (server Attached Storage)architecture,attaching all the storage devices directly to the machines.This kind of storage strategy can‘t meet the requirement of our BEPC II/BESⅢ project properly.Thus we design and implement a SAN-based computing environment,which consists of several computing farms,a three-level storage pool,a set of storage management software and a web-based data management system.The feature of ours system includes cross-platform data sharing,fast data access,high scalability,convenient storage management and data management.  相似文献   

7.
Cosmic-ray data of 90 M events have been collected and used for calibration,alignment as well as detector tuning. A special tracking algorithm for the BESⅢ muon counter is developed and verified with Monte-Carlo simulation and then further confirmed with the cosmic-ray data. The obtained strip resolutions are in good agreement with the design values. A new alignment approach for the BESⅢ muon counter is confirmed with the cosmic-ray data and proposed to be used in future analysis of experimental data.  相似文献   

8.
Cosmic-ray data of 90 M events have been collected and used for calibration,alignment as well as detector tuning. A special tracking algorithm for the BESⅢ muon counter is developed and verified with Monte-Carlo simulation and then further confirmed with the cosmic-ray data. The obtained strip resolutions are in good agreement with the design values. A new alignment approach for the BESⅢ muon counter is confirmed with the cosmic-ray data and proposed to be used in future analysis of experimental data.  相似文献   

9.
We present physics opportunities and topics with the s states(strangeonia)that can be studied with the BES detector operating at the BEPC collider.Though the φ and η/ states have long been established experimentally,only a handful of strangeonia are well known,in contrast to the rich ccharmoium system.An overview of the s states and their experimental status is presented in this paper.The BES experiment has collected the world’s largest samples of J/ψ,ψ(2S),ψ(3770),and direct e+e-annihilations at energies below the J/ψand above 3.8 Ge V,and will continue to accumulate high quality,large integrated luminosity in theτ-charm energy region.These data,combined with the excellent performance of the BESⅢ detector,will offer unprecedented opportunities to explore the s system.In this paper we describe the experimental techniques to explore strangeonia with the BESⅢ detector.  相似文献   

10.
Based on all the features of the KLOE online software,the online calibration system performs current calibration quality checking in real time and starts automatically new calibration procedures when needed.Acalibration manager process controls the system,implementing the interface to the online system,receiving information from the run control and translating its state transitions to a separate state machine.It acts as a “ calibration run controller“and performs failure recovery when requested by a set of process checkers.The core of the system is a multi-threaded OO histogram server that receives histogramming commands by remote processes and operates on local ROOT histograms.A client library and C,fortran and C application interface libraries allow the user to connect and define his own histogram or read histograms owned by others using an bool-like interface.Several calibration processes running in parallel in a destributed,multiplatform environment can fill the same histograms,allowing fast external information check.A monitor thread allow remote browsing for visual inspection,Pre-filtered data are read in nonprivileged spy mode from the data acquisition system via the Kloe Integrated Dataflow,privileged spy mode from the data acquisiton system via the Kole Integrated Dataflow.The main characteristics of the system are presented.  相似文献   

11.
The chamber production and installation of the BESⅢ MUON identifier system have been finished. The cosmic ray test result after installation shows that the average efficiency is bigger than 95% and can meet the requirement of the design report. A database including all the chamber parameters and performance data has been constructed and is accessible online. The quality control procedures during the production and the database are described.  相似文献   

12.
After examination of the designed high voltage power supply system of the BESⅢ drift chamber in the beam test of the full length prototype of drift chamber, a full system covering all the channels of high voltage was installed. The system's training and the high voltage value adjustment were carried out in the cosmic ray test of the BESⅢ drift chamber. The cosmic ray test for the full system and its final installation on the BESⅢ drift chamber were reported. The full system of high voltage power supply works stably and reliably.  相似文献   

13.
A measurement of the number of J/ψ events collected with the BESⅢ detector in 2009 and 2012 is performed using inclusive decays of the J/ψ. The number of J/ψ events taken in 2009 is recalculated to be(223.7±1.4)×10~6, which is in good agreement with the previous measurement, but with significantly improved precision due to improvements in the BESⅢ software. The number of J/ψ events taken in 2012 is determined to be(1086.9±6.0)×10~6. In total, the number of J/ψ events collected with the BESⅢ detector is measured to be(1310.6±7.0)×106, where the uncertainty is dominated by systematic effects and the statistical uncertainty is negligible.  相似文献   

14.
The decays of J/ψ → μ^+μ^- and J/ψ → e^+e^- are studied by Monte-Carlo simulation, based on the Beijing Spectrometer (BES)Ⅲ offtine software system. The methods of determination of the J/ψ event number via J/ψ → μ^+μ^- and J/ψ → e^+e^- are presented, respectively. These methods can be used to determine the J/ψ event number for the coming BESⅢ J/ψ data sample.  相似文献   

15.
This note describes the construction of hardware and software of the BESPC-FARM and BES offline data analysis environment in Linux platform.The job management packages NQS is described.The performance of the BESPCFARM also be presented.  相似文献   

16.
17.
Using experimental data, Monte Carlo tuning is implemented for performance parameters associated with the scintillation counters and readout electronics of the BESⅢ time-of-flight(TOF) system, as part of the full simulation model. The implementation of the tuning is described for simulations designed to reproduce the performance of a number of TOF system parameters, including pulse height, hit efficiency, time resolution, dead channels and background. In addition, comparisons with experimental data are presented.  相似文献   

18.
After the construction of the BESⅢ drift chamber, a long period of cosmic rays test is necessary to verify its performance. This also provides a good opportunity to integrate the detector readout electronics and Detector Control System (DCS) into a unified working system. The goal of the DCS is to guarantee reliable physics data quality and the safe operation of the detector. It monitors and controls the HV, gas, VME crates and the nvironmental variables. The upper-level system is mainly developed from LabVIEW and the lower-level system mainly uses MCU and PLC technology. The system is designed to be highly flexible and scalable so that it can be applied to other detectors with little or no change. In the immediate future, it will be integrated into the entire BESⅢ Slow Control System.  相似文献   

19.
Front-end readout electronics have been developed for silicon strip detectors at our institute. In this system an Application Specific Integrated Circuit (ASIC) ATHED is used to realize multi-channel energy and time measurements. The slow control of ASIC chips is achieved by parallel port and the timing control signals of ASIC chips are implemented with the CPLD. The data acquisition is carried out with a PXI-DAQ card. The software has a user-friendly GUI developed with LabWindows/CVI in the Windows XP operating system. The test results show that the energy resolution is about 1.14% for alpha at 5.48 MeV and the maximum channel crosstalk of the system is 4.60%. The performance of the system is very reliable and is suitable for nuclear physics experiments.  相似文献   

20.
傅成栋 《中国物理 C》2008,32(5):329-337
The results of a study of event tagging strategies for elementary physics processes in the τ-charm region are presented. The algorithm for online event filtering is optimized by adopting the information provided by different sub-detectors according to their strengths and capacities. The algorithm is tested with various generated physics and background events. The results indicate that the algorithm satisfies the requirements of BESⅢ physics analysis and its  相似文献   

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