Functional characteristics and radiation tolerance of AToM, thefront-end chip of BaBar silicon vertex tracker

The readout chip designed to process the microstrip signals in the BaBar Silicon Vertex Tracker (SVT), after being realized twice in a radsoft technology has been transferred into the final radhard process. So far the circuit has gone through four different radhard submissions, one aiming at providing a preliminary insight into the characteristics of the radhard chip, the other ones constituting pre-production and production runs. Chips from these submissions have undergone a thorough set of tests addressing functional aspects, noise parameters and effects of radiation on signal and noise behavior. The present paper discusses the results of these tests and describes the final version of the circuit which has been proven to successfully meet the experiment requirements     

Chooz 中微子探测器电子学系统的设计

介绍了Ｃｈｏｏｚ中微子探测器中的电子学系系统,简述ＥＭＩ９３５６ＫＢＡ Ｂ５３型光电倍增管的性能和组成该电子学系统的信号扇入／扇出、信号多级触发、时间数字转换、波形数字化以及数据获取等各系统的设计原理。     

Implementation and performance of the third level muon trigger of the ATLAS experiment at LHC

The trigger system of the ATLAS experiment at the LHC aims at a high selectivity in order to keep the full physics potential while reducing the 40 MHz initial event rate imposed by the LHC bunch crossing down to /spl sim/100 Hz, as required by the data acquisition system. Algorithms working in the final stage of the trigger environment (Event Filter) are implemented to run both in a "wrapped" mode (reconstructing tracks in the entire Muon Spectrometer) and in a "seeded" mode (according to a dedicated strategy that performs pattern recognition only in regions of the detector where trigger hypotheses have been produced at earlier stages). The working principles of the offline muon reconstruction and identification algorithms (MOORE and MuId) implemented and used in the framework of the Event Filter are discussed in this paper. The reconstruction performance of these algorithms is presented for both modes in terms of efficiency, momentum resolution, rejection power and execution times on several samples of simulated single muon events, also taking into account the high background environment expected for ATLAS.     

BES-ⅢTOF子触发系统触发判选功能在可编程逻辑器件中的实现

北京正负电子对撞机谱仪的飞行时间计数器触发子系统,需从前端读出电子学接收368 bits快时间击中信号,按物理实验要求的触发逻辑产生7 bits触发条件信息,实时发送给主触发逻辑,以产生一级触发信号L1;并向径迹配对逻辑实时发送136 bits位置信息,以推算粒子飞行径迹;同时根据L1信号对事例进行判选、组装,向DAQ系统提供所有有效事例的数据包,以供离线分析.我们对该系统研制秉持可重构的设计理念,大量使用可编程逻辑器件FPGA,增加设计的灵活性和可靠性,减小印刷电路板设计的复杂度,节省PCB布板空间.本文介绍主触发处理FPGA中核心触发逻辑功能的设计与实现.     

同步加速器束流能量自动切换控制系统

带电粒子放射治疗中3D主动治疗方式需要不同的束流能量照射不同的病灶切面,这就需要同步加速器控制系统能实现多级束流能量的自动切换控制并提供接口对接治疗计划进行自动变能控制。本文开发了同步加速器束流能量切换控制系统,同步加速器的前端服务器中存储着执行1个同步加速器加速周期所需的全部控制数据集,其中控制数据通过索引标号对其进行区分,同步事例信息是同步加速器多级束流能量切换的触发信号。当前端控制器被同步时间系统的同步事例触发激活后,从DSP波形发生器的SDRAM空间中读出磁铁电源、高频等控制数据进行数据切换。同步事例信号包含同步触发信息、束流能量控制数据的索引信息和控制数据的更新操作信息。多级束流能量自动切换控制系统能实现255级束流能量间自动切换控制（碳束能量在50～500 MeV间切换,步长可控制在1.77 MeV）,完全能满足实际中碳束能量在50～500 MeV间以10 MeV为步长的自动切换控制。     

A Proportional Wire Chamber Electronics System Utilizing CAMAC

This report describes a system of electronics to be used with a proportional wire chamber hodoscope. The system, which uses CAMAC packaging and data handling philosophy, consists of octo (8 channel) wire signal amplifiers, octo 4-bit per wire latch modules, gate fanout modules, crate controllers, and two types of data processor-interface units to the SDS 9300 computer. System operation is explained, and each component is described.     

The data-acquisition system for the CMS tracker beam tests

This paper describes the conception and the development of a real-time data-acquisition system for prototype detectors of the Tracker being designed for the compact muon solenoid (CMS) experiment at the Large Hadron Collider of CERN, European Laboratory for Particle Physics, Geneva, Switzerland. The rationale for the development of a dedicated data-acquisition system was the need to perform two fundamental beam tests (the “Milestone Barrel 1” and “Milestone Forward 1”), with large-scale prototypes of the detectors planned as the baseline design. The number of readout channels, the complexity of the readout electronics, and the stringent requirements of the milestone tests mandated that a thorough understanding of the issues related to the physics of the detectors themselves be coupled with the application of leading-edge electronic and software engineering technologies. The implementation described in this paper is based on a distributed architecture. An event builder CPU handles the two main tasks of synchronizing a variable number of front-end processors and formatting the data in preparation for the transfer to a dedicated high-performance storage system, while the front-end processors handle the hardware and the real-time readout. Additional workstations are used to decouple the actual task of transferring the data files and monitoring the detector performance on-line from the readout farm. The system has been successfully operated during the two aforementioned Milestone tests, allowing the CMS Tracker collaboration to pass them, with the simultaneous readout of up to 40000 detector channels. The results of the two Milestones have led to the compilation of the “Tracker Technical Design Report”. Subsequently, the same readout system has been used for a number of other beam tests, and it has formed the basis for the development of further, more advanced data-acquisition systems for the new readout electronic of the CMS Tracker     

Fast-digitizing and track-finding electronics for the vertexdetector in the Opal experiment at the Large Electron Positron Collider(LEP) at CERN

The vertex detector front-end electronics are described. It comprises fast analog-to-digital conversion circuits and a fast programmable track trigger processor. The function of the electronics is to examine, within one large electron-positron beam crossing (22 μs), data generated in the detector for the evidence of charged particle tracks. Measurements of ionization drift times are based on a gated 93-MHz oscillator synchronized to a precision crystal clock and give points in space. The axial positions of these points along the detector are found by analyzing the difference in time of arrivals of signals at the ends of the detector (z by timing). Particle tracks are found by 36 track finders operating in parallel and are matched by semicustom coincidence chips. The track information is used in the first stage of data reduction in the Opal experiments (the first-level trigger)     

Feasibility of the hardware muon trigger track finder processor inCMS

This paper describes a feasibility study for the design of the muon trigger track finder processor in the high-energy physics experiment compact muon solenoid (CMS), planned for 2005, at CERN. It covers the specification, proposed method, and a prototype implementation. Comparison between several other measurement methods and the proposed one are carried out. The task of the processor is to identify muons and measure their transverse momenta and locations within 350 ns. It uses data from almost 200000 detector cells of drift tube muon chambers. The processor searches for muon tracks originating from the Interaction point by joining the track segments provided by the drift tube muon chamber electronics to full tracks. It assigns transverse momentum to each reconstructed track using the track's bend angle     

A Radiation-Hardened I2L 8 × 8 Multiplier Circuit

Development of improved Substrate Fed I2L (SFL) processing has been combined with geometry and fanout constraints to design a radiation hardened LSI 8 × 8 Multiplier. This paper will describe details of the process and circuit design and give resultant electrical and radiation test performance.     

一种可用于在线触发的移位寻迹方法

介绍了一种简单高速移位寻迹方法,这种方法易用可编程逻辑器件实现,可以快速高效地找到事例径迹,同时该方法容易分解为流水线结构,响应速度更快,可以用于在线触发系统。     

A Dedicated Line-Processor as Used at the SHF

A hardwired trigger processor was used at the SLAC Hybrid Facility to find evidence for charged tracks originating from the fiducial volume of a 40? rapid-cycling bubble chamber. Straight-line projections of these tracks in the plane perpendicular to the applied magnetic field were searched for using data from three sets of proportional wire chambers (PWC). This information was made directly available to the processor by means of a special digitizing card. The results memory of the processor simulated read-only memory in a 168/E processor and was accessible by it. The 168/E controlled the issuing of a trigger command to the bubble chamber flash tubes. The same design of digitizer card used by the line processor was incorporated into the 168/E, again as read only memory, which allowed it access to the raw data for continual monitoring of trigger integrity. The design logic of the trigger processor was verified by running real PWC data through a FORTRAN simulation of the hardware. This enabled the debugging to become highly automated since a step by step, computer controlled comparison of processor registers to simulation predictions could be made.     

快速鉴别空气中人工放射性污染：β衰变比值法

本文阐述了用“β衰变比值法”鉴别空气中长寿命人工β放射性污染的原理。介绍了依据该原理设计的仪器设备,从实测数据分析得到,当天然β气溶胶浓度为7.49Bq/m~3(约2×10~(-13)Ci/L),取样1h,取样量为3.36m~3空气时,取样结束后60min,检出水平为1.82Bq/m~3(4.9×10~(-14)Ci/L);取样结束后150min,检出水平1.77Bq/m~3(4.8×10~(-14)Ci/L)。     

Recent results for the CMS tracker silicon detectors

The paper reports on a detailed study of the radiation resistance of p⁺ on n silicon microstrip detectors for the CMS tracking system. From this study, it is seen that the use of low-resistivity substrates with 〈100〉 crystal lattice orientation promises excellent performance of the Inner Tracker after heavy irradiation in the Large Hadron Collider environment. Furthermore, the advantage of using detectors thicker than 300 μm in the Outer Tracker is discussed together with experimental measurements on prototypes     

Trigger control in a high energy physics experiment

Control and diagnostic tools for the event-filtering system (trigger) of the L3 experiment at the LEP (Large Electron Positron) collider have been implemented using an expert system. The structure and behavior of the trigger electronics has been modeled using the hybrid framework (allowing both frame-based design and rule-based reasoning) of the shell NEXPERT Object, which also provides a user friendly interface. An open architecture allows the integration in the system of conventional and widespread tools, like procedural languages and database management systems, and an easy interface to the whole online environment. The project goals, base model, development tools, and present implementation and future development of the trigger control are described     

Initial Beam Test Results from a Silicon-Strip Detector with VLSI Readout

Silicon detectors with 256 strips, having a pitch of 25 ?m, and connected to two 128 channel NMOS VLSI chips each (Microplex), have been tested in relativistic charged particle beams at CERN and at the Stanford Linear Accelerator Center. The readout chips have an input channel pitch of 47.5 ?m and a single multiplexed output which provides voltages proportional to the integrated charge from each strip. The most probable signal height from minimum ionizing tracks was 15 times the rms noise in any single channel. Two-track traversals with a separation of 100 ?m were cleanly resolved.     

高密度塑料闪烁体探测器的数据获取系统设计

由中国科学院近代物理研究所承担的塑料闪烁体探测器研究项目,其目标是开展空间粒子探测、重构入射电子轨迹、区分电子和光子、鉴别重离子。为配合该探测器测试工作,设计了一套完备的数据获取电路(DAQ)与上位机软件。DAQ接收4块前端电子学(FEE)板的数据,可完成360路电子学通道的数据读出;接收上位机的控制命令并分发给各FEE;接收探测器的击中信息并产生触发信号;接收FEE的遥测数据并传给上位机。该DAQ与上位机通过USB总线和RS232总线实现实时通信。上位机软件基于LabWindows/CVI软件平台开发,实现对FEE电子学系统的控制、数据读取与保存,以及FEE系统运行状态参数信息的实时显示。该数据获取系统电路结构紧凑、功能完善,上位机软件具有良好的人机交互界面。经现场实际运行,DAQ与上位机软件满足设计要求,目前已成功应用于塑料闪烁体探测器读出电子学测试系统。     

The trigger system of the first CMS tracker beam tests

The trigger for the first compact muon solenoid (CMS) tracking beam tests is a dedicated system for analog multiplexed front-end electronics. With this first generation of electronics dedicated to CMS tracker detectors, some new specific development was necessary to read it with a multicrate distributed data acquisition (DAQ) system. The goal of this development was to reach a high scalability of experiment subsystems and a good robustness for test beams. Each subsystem had to be independent from the others, both from the hardware and software point of view. Remote control software for this system as well as further monitoring facilities were the required functions of the trigger system     

Readout electronics for CSR-ETF silicon strip array detector system

A readout electronics has been developed for the silicon strip array detector system of HIRFL-CSR-ETF.It consists of 48 front end electronics(FEE)boards,12 PXI-DAQ boards and one trigger board.It can implement energy and time measurements of 4608 channels.Each FEE board is based on 6 ASICs(ATHED),which implements energy and time measurements of 96 channels.The PXI-DAQ board meets requirements of high-speed counting and amount of readout channels and can process signals of 4 FEEs.The trigger board is developed to select the valid events.The energy linearity of the readout electronics is better than 0.3%in the dynamic range of 0.1-0.7V.In the test with a standard triple alpha source,the energy resolution was 1.8%at 5.48 MeV.This readout electronics enables the silicon strip array system to identify particles of A14.     

The Trigger System of the MAGIC Telescope

The MAGIC telescope aims at the detection of very low energy gamma rays (E>30 GeV) through the atmospheric emission of Cherenkov light. The high background rate originating from the night sky background, muons, hadronic showers and bright stars sets a serious challenge to this goal. Application of topological selection cuts at trigger level can have a big impact on background reduction allowing the telescope to operate at lower thresholds and reducing the minimum detectable energy. The trigger of the MAGIC telescope is a two-level system following a pipeline philosophy, similar to those adopted in high energy physics experiments. Operative since October 2002, the trigger system has been a key point in the commissioning of the MAGIC telescope that is now taking data. The trigger hardware is described in detail