高能物理实验径迹系统流式数据获取框架的研究

高能物理实验研究基本粒子及其相互作用,需要获取和分析大量的实验数据以发现新粒子或测量已知粒子的特性.随着高能物理实验规模的不断扩大以及加速器能量和亮度的不断提升,海量数据的获取、处理及分析将更具挑战性.在高能物理实验中,径迹系统探测器的通道数和数据量尤为巨大,为了读出和在线处理径迹系统探测器产生的海量数据,本文结合Ha...     

多路穆斯堡尔谱数据获取与处理系统

本文叙述了一个以BC3-80微型计算机为基础,通过一个以Z80-CPU为中心的控制机与8个带有存贮器的数据获取通道组成的多路数据获取与处理系统。这个系统除能对8个通道的数据进行数据获取外,同时可以对其进行显示、保存和数据处理。它与穆斯堡尔谱仪部件相接,构成一个恒加速穆斯堡尔谱仪系统。 这个系统配上高计数率多丝正比室,可以使穆斯堡尔谱的探测效率大大提高。多丝室中的每根丝的信号分别通过各自的放大器、单道分析器,由相应的数据通道记录下来,然后由微机进行相加和处理。另一方面,这个系统还可以利用不同的通道同时测出样品的透射谱和散射谱,同时得到样品的内部和表面信息。     

（e,2e）电子动量谱仪的多参数获取和处理系统

本文介绍研制成功的（ｅ，２ｅ）电子动量谱仪的多参数获取和处理系统。这个系统有几个特点：一是５个数据获取通道并行转换数据；二是在微机支持下，每个通道相当于一个多道；三是根据需要可很方便地分开组合数据获取的通道数，即可作为单通道微机多道分析器使用，又可作为一维或二维位置灵敏探测器的数据获取和处理系统使用；最后一点是系统实时获取时，可在线处理数据并在图形显示上分时显示符合时间谱及电离能谱。     

重子数实验的数据获取系统

概述了重子数实验的实验装置,其中包括探测器装置和数据获取系统。简述了探测器的组成、功能和性能;着重叙述了数据获取系统之构成、功能及所解决的问题。触发判选与数据获取系统较大地抑制了噪声,提高了信噪比和测量精度。该数据获取系统有一定的通用性,其设计方案不仅用于重子数实验,也适用于其他实验如双β实验中所需的符合测量等。     

CSR外靶实验数据获取原型系统设计

介绍了为兰州重离子加速器冷却储存环外靶实验设计实现的一套数据获取原型系统。系统借鉴流处理、Map-reduce和Bigtable等技术或模型的思想,采用一套流处理节点构成的网络完成数据获取任务。系统支持对流处理网络拓扑结构自由调整,灵活地实现并行处理和负载均衡。同时通过为不同类型探测器定义接口标准以及支持用户自定义节点添加,实现大型物理实验调试和实验过程中的各种数据获取需求。目前系统已与探测器及前端电子学一起进行了一系列联合测试,验证了系统的可行性和稳定性。     

“天光”装置计算机测控系统设计与调试

建立了“天光”装置的计算机测控系统。应用这一系统,实现了对装置运行状态的自动监视,报警,对装置的电源系统,率电和触发过程的计算控制,以及对实验数据的自动获取,存储和处理。     

腔式束流位置探头初步束流实验与参数仿真

针对下一代FEL装置束流位置精确测量的需求,中国科学院上海应用物理研究所研制了5712MHz高Q腔式BPM测量系统样机。其中ADC分辨率及数据长度是影响系统位置分辨率的关键参数。为寻求参数的最优化,采用束流实验结合蒙特卡洛的方法对此问题进行了研究。利用上海深紫外自由电子激光装置标定了探头位置因予,在此基础上采用蒙特卡洛方法,分别对射频采样、中频采样数据采集处理方法中的数据长度、ADC的分辨率要求进行了仿真。结果表明,射频采样方法由于现有超高速ADC分辨率的限制,难以实现亚微米量级的精确测量,更适合于样机的快速参数验证与评估;中频采样方法可充分发挥百MHz ADC高分辨率的优点,当ADC分辨率高于14位时,系统位置分辨率即可好于亚微米,是腔式BPM系统在线数据采集处理的最优选择。采用FFT方法对本样机信号进行处理,射频采样和中频采样的最优数据长度分别为8192点、256点。     

基于苹果-Ⅱ微机的数据获取与处理系统

研制了一个基于APPLE-Ⅱ微机的数据获取与处理系统。功能完善,通用性强,使用方便,易于修改和扩充,具有若干特色。本系统具有数据采集、数据保存、装入数据、图形显示、打印输出、图形绘制和数据处理等功能。实验者可以设定延迟时间、同步电压、采集速率、实验参数和实验条件。实验数据,参数和条件有机联系,统一保存于一个文件中以便对数据进行分析和比较。本系统是为各类小型实验装置设计的。1986～1987年已成功地用于MM-2和MM-4实验装置,获得若干重要结果。     

基于FPGA的EAST-ICRF实时监控系统设计

在全超导托卡马克核聚变实验装置(EAST)上进行核聚变试验时,离子回旋共振加热(ICRF)是该试验过程中加热等离子体的主要方法之一,而对发射机、传输线、真空室以及天线中的重要参数进行实时监测是托卡马克装置中ICRF对等离子体进行功率耦合的重要保障。提供了一种采用FPGA的ICRF实时监控系统设计方案、AD9252芯片以及SN74LS14型号施密特触发器进行数据采样,实现对各故障信号的实时显示、报警以及信号源的及时切断,同时利用FPGA可重复编程的特点,便于后期对系统进行维护和升级。     

4π BaF2装置的触发系统研究

设计了一套γ全吸收型BaF₂探测装置,用于中子辐射俘获反应截面的在线测量,其中信号测量部分采用了基于高速采集卡的数字化脉冲波形采集技术。并设计了一套触发系统,由触发单元产生的信号作为数据获取系统的外触发控制数据采集,以在数据测量过程中剔除绝大多数本底事件。触发系统采用了符合测量技术,通过多通道、多参数之间的符合测量,实现释放瞬发级联γ射线的中子俘获反应事件的判选和本底的剔除。本文对触发系统的电路设计和实验测试进行了阐述。     

Design of the stripping unit and the electromagnetic analysis unit for the E//B NPA on HL-2A/2M tokamak

An E//B neutral particle analyzer is under development for fast ion diagnosis on HL-2A/2 M tokamak. The stripping unit is composed of a stripping room (equipped with two differential tubes and a gas supply bellows), a vacuum chamber and a vacuum pumping system. The stripping efficiency of the stripping room is calculated in the form of global efficiency R × f₊₁, where R is the non-scattered-away rate and f₊₁ is the fraction of charge state +1. The magnetic field of the E//B analyzer is produced with a permanent magnet. The yoke and the poles of the magnet are made of mild steel and the magnet plates are made of NdFeB. The magnetic poles are specially designed to focus the ion trajectories and to increase the use rate of the magnet. The shape of the magnet and the electric plates are carefully designed so that the ions are dispersed into two lines of H⁺ and D⁺ on the detector plane. For each line, the energy increases from 10 to 200 keV from one side to another.     

Recent ICRF coupling experiments on EAST

Recent ion cyclotron resonance frequency(ICRF) coupling experiments for optimizing ICRF heating in high power discharge were performed on EAST. The coupling experiments were focus on antenna phasing and gas puffing, which were performed separately on two ports of the ion cyclotron resonance heating(ICRH) system of EAST. The antenna phasing was performed on the I-port antenna, which consists of four toroidally spaced radiating straps operating in multiple phasing cases; the coupling performance was better under low wave number ∣k_‖∣(ranging from 4.5 to 6.5). By fuelling the plasma from gas injectors, placed as uniformly spaced array from top to bottom at each side limiter of the B-port antenna, which works in dipole phasing, the coupling resistance of the B-port antenna increased obviously.Furthermore, the coupling resistance of the I-port antenna was insensitive to a smaller rate of gas puffing but when the gas injection rate was more than a certain value(1021 s~(-1)), a sharp increase in the coupling resistance of the I-port antenna occurred, which was mainly caused by the toroidal asymmetric boundary density arising from gas puffing. A more specific analysis is given in the paper.     

Probabilistic simulation of cable performance and water based protection in cable tunnel fires

Nuclear power plants contain a significant amount of fire load in form of electrical cables. The performance of the cables is interesting both from the fire development and system failure viewpoints. In this work, cable tunnel fires are studied using numerical simulations, focusing on the fire spreading along power cables and the efficiency of the water suppression in preventing the cable failures. Probabilistic simulations are performed using Monte Carlo technique and the Fire Dynamics Simulator (FDS) as the deterministic fire model. The primary fire load, i.e. the power cables are modelled using the one-dimensional pyrolysis model, for which the material parameters are estimated from the experimental data. Two different water suppression systems are studied. The simulation results indicate that using either suppression system decreased the heat release rate in the tunnel to less than 10% of the non-suppressed case. Without water suppression, the cables of the second sub-system were damaged in almost all fires, but when either of the studied water suppression systems was used, the probability of the cable failures was decreased to less than 1%. This result indicates that in current scenario, the probability of losing both sub-systems is determined directly by the suppression system unavailability.     

Large eddy simulation of unsteady flow in vortex diode

Vortex diode, as an important component in power fluidics, has been widely used in nuclear reprocessing engineering for about two decades. The fluidic system with vortex diodes is always working under a condition with a pulsant pneumatic power input. However, no detailed analysis of the unsteady flow inside the vortex diodes is available. Therefore, we carried out large eddy simulation (LES) to investigate the transient start-up process on the foundation of the experiment by Jacob et al. The numerical results were compared with the experimental data. It is shown that the special flow-time profiles in the start-up process are well predicted. From a further analysis on the internal flow, it is indicated that the change of flow rate with time is relevant to the varying of internal flow pattern and the swirling level. The above-mentioned methods and results of the vortex diode are of great guiding significance to predict the transient performance of the fluidic transfer system.     

Experimental study on gas-injection enhanced circulation performed with the CIRCE facility

This paper describes the results of an experimental campaign concerning the possibility of achieving a steady state circulation by gas-injection in a pool containing lead–bismuth eutectic (LBE) as working fluid. The activity was aimed at gaining information about the basic mechanisms of the gas injection enhanced circulation intended as a pumping system for a liquid metal cooled reactor. In particular, the paper is focused on the experimental work performed in the CIRCE large-scale facility, installed at the ENEA Brasimone Centre for studying the fluid-dynamic and operating behaviour of ADS reactor plants cooled by LBE. The gas enhanced circulation tests were carried out for different LBE temperatures (from 200 to 320 °C), under isothermal conditions and with a wide range of argon injected flow rates (from 0.5 to 7.0 Nl/s). The gas is injected from the bottom of the riser, by means of an appropriate nozzle, and the liquid metal flow rate is measured by a Venturi-Nozzle flow meter installed in the single phase part of the test section. The obtained results allowed formulating a characteristic curve of the system and evaluating the void fraction distribution along the riser path by means differential pressure measurements, which play an important role to generating the driving force for the circulation.     

基于Z′参数的高强铝合金稳态蠕变速率可靠性研究

建立了基于速率温度参数模型的新型高强铝合金Z′参数表达式及稳态蠕变速率 可靠度预测方法,Z′参数表征稳态蠕变速率数据偏离速率温度参数模型主曲线的程度。结合实测数据,研究了Z′参数的统计分布规律。基于Z′参数,分别得出新型高强铝合金实验应力 速率温度参数 可靠度曲线和温度 许用应力 可靠度曲线。结果显示,新型高强铝合金Z′参数满足正态分布规律。稳态蠕变速率预测上限随可靠度的增加而升高。外推至稳态蠕变速率上限10-7 h-1时,新型高强铝合金在50、80 ℃下的许用应力（可靠度997%）分别为4700、2945 MPa。与传统安全系数法相比,基于Z′参数的预测结果更合理。     

The properties of N-doped diamond-like carbon films prepared by helicon wave plasma chemical vapor deposition

In this paper, N-doped diamond-like carbon(DLC) films were deposited on silicon substrates by using helicon wave plasma chemical vapor deposition(HWP-CVD) with the Ar/CH_4/N_2 mixed gas. The surface morphology, structural and mechanical properties of the N-doped DLC films were investigated in detail by scanning electron microscopy(SEM), x-ray photoelectron spectroscopy(XPS), Raman spectra, and atomic force microscopy(AFM). It can be observed from SEM images that surface morphology of the films become compact and uniform due to the incorporation of N. The maximum of the deposition rate of the films is 143 nm min~(-1), which is related to the high plasma density. The results of XPS show that the N incorporates in the films and the C-C sp~3 bond content increases firstly up to the maximum(20%) at 10 sccm of N_2 flow rate, and then decreases with further increase in the N_2 flow rate. The maximum Young's modulus of the films is obtained by the doping of N and reaches 80 GPa at 10 sccm of N_2 flow rate, which is measured by AFM in the scanning probe microscope mode. Meanwhile, friction characteristic of the N-doped DLC films reaches a minimum value of 0.010.     

Dispersion and damping rate of Langmuir wave in space plasma with regularized Kappa distributed electrons

The dispersion of Langmuir wave (LW) in an unmagnetized collisionless plasma with regularized Kappa distributed electrons is investigated from the kinetic theory. The frequency and damping rate of LW are analyzed for the parameters relating to the source region of a type III solar radio burst. It is found that the linear behavior of LW is greatly modified by the suprathermal index κ and the exponential cutoff parameter α. In the region κ < 1.5, the damping rate of LW will be much larger than the one with Maxwellian distributed electrons. Hence, the nonlinear process of LW in low κ region may exhibit different properties in comparison with the one in large κ region.     

A distributed control system for picosecond accelerator at SINAP

The picosecond accelerator （PA） is a low energy electron linear accelerator facility under commissioning, which is built for the experiment of ps level pulse radiolysis in Shanghai Institute of Applied Physics （SINAP）. A practical distributed DA＆C system for this facility has been developed. In view of the upgrading-ability and maintainability of the control system and controlled devices, Advantech distributed intelligent DA＆C products are adopted into the control system. ADAM 5000/TCPs with the protocol of Modbus/TCP are employed to accomplish data acquisition and device control. The PC-compatible programmable logic controller, ADAM-5511. is also adopted to handle the interlocks and the emergency events. On the software side, the integrated software package Kingview V6.5, which fi＇iendly supports all Advantech products, has been used to develop the upper layer control logic and process the data. This paper describes the control system design and system architecture, The intelligent ADAM controllers and the software platform are also discussed in detail.     

一种STD总线微机支持的多通道核数据获取系统

本文介绍—种STD总线微机支持的多通道核数据获取系统,它具有性能可靠,组合灵活,结构紧凑,易于系统扩充、更新和维护等优点。可在较严酷的环境下工作,尤其适用于中、小规模的核物理、空间物理及大型实验系统的前端和预先研究系统中。