System aspects of the ILC-electronics and power pulsing
System aspects of the ILC-electronics and power pulsing
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ILC 的系统方面 - 电子和功率脉冲
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发表时间：
2007
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通讯作者：
P. Göttlicher
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作者：
P. Göttlicher
对国际直线对撞机(ILC)实验电子学的要求是由加速器短序列(1ms)的束团结构和精密物理驱动的，其中束团到束团滞后为0.3μ，S被长空间隔(199ms)中断。基于CALICE Collaboration的发展，提出了一种高颗粒密度量热测量系统。讲座涵盖了系统方面-紧凑型传感器如硅二极管和多像素盖革模式光电传感器-机电与组件嵌入到印刷电路板中，-将传感器附近所需的功能集成到低功率ASIC中，-DAQ链，其中每个通道自行触发并将数据选择安装到PC中-校准热量计。随着亿级通道数量的增加，功耗和散热问题必须得到认真的研究。计算表明，可以避免热量计内部的主动冷却。但实现这一目标的关键是使用加速器的低占空比(0.5%)来重启主要用户，并设计低功耗(25μW/通道)的专用集成电路。对于功率循环，提出了一种保持电流波动的局部概念，以避免电磁干扰问题，并通过中等截面的导线向探测器内电子器件提供直流电流。其中一些想法已经在物理和组件研究的原型中实现。该系统集成了14,000个频道，在CERNestBeam上安装了两个月。收集了2亿个电子和介子，存储了15T字节的数据。这些数据很好地展示了证明粒子流算法实现高能量分辨率所需的簇射开发的细节。I.由加速器和加速器中的物理定义的电子学的一般条件，ILC电子和正电子将在0.5TeV以上的能量下碰撞。这使得重粒子的高精度物理学成为可能，但电子和正电子的相互作用速度很低。由于超导加速，这些束流被打包成1毫秒长的列车，中间有199毫秒的长空载周期。在列车运行过程中，束的间隔为0.3μS。在电子设计中利用这些特点，可以保持系统的充分性，并且在某些阶段简单。在电子学方面，要求遵循快速的束到束结构(0.3μS)，甚至为信号提供更快的脉冲分析，为此时间信息改进了能量测量。但快速信号只有0.5%的时间出现在火车上。在剩下的时间里，快速电子设备是不需要的。数据采集系统可以利用列车的低占用率和较长的间歇时间为契机，最大限度地减少探测器内部的基础设施。E+e−碰撞在TeV尺度上的物理学也定义了对探测器设计的要求。为了达到高精度测量重颗粒性质的目的，必须开发新的概念和技术。作为案例研究，重粒子的衰减链被用来制定探测器的要求。T，H→Z，W→轻子或喷注探测器设计的目的是通过重建所涉及的矢量玻色子的质量来区分它，即使从喷注中也是如此。这需要跟踪、顶点检测和高能量分辨率，即使对于喷气式飞机也是如此：
The requirements for the electronics of an experiment at the international linear collider (ILC) are driven by the bunch structure of the accelerator short trains (1ms) with bunch to bunch lag of 0.3μs interrupted by long empty intervals (199ms) and the precision physics. Based on developments of the CALICEcollaboration a system for high granular dense calorimetry is presented. The talk covers the system aspects — of compact sensors as Si-diodes and multi-pixel Geiger mode photo sensors, — of the electromechanics with components embedded into the PCB’s, — of integrating the functionality needed nearby the sensor into low power ASIC’s, — of a DAQ-chain, in which each channel triggers on its own and the data selection is installed into PC’s and — of calibrating the calorimeter. With the high number of 100 million channels the power consumption and cooling have to be investigated carefully. Calculations demonstrate, that active cooling inside the calorimeters can be avoided. But essential for this goal is using the low duty cycle (0.5%) of the accelerator to power cycle the major consumers and designing an ASIC for low power (25μW/channel). For the power cycling a concept is developed, which keeps the current fluctuation local to avoid EMIproblems and to supply the in-detector electronics with DCcurrent through wires weith moderate cross section. Some of the ideas are already realized in a prototype for physics and component studies. The setup integrates 14 thousand channels and was installed for two month at CERNtestbeam. 200 million of electrons and pions are collected and 15T-Byte of data are stored. The data nicely show the details of a shower development needed to prove the particle flow algorithm for high energy resolution. I. GENERAL CONDITIONS FOR THE ELECTRONICS DEFINED BY ACCELERATOR AND PHYSICS In the accelerator ILC electrons and positrons will collide at energies above 0.5TeV. This allows high precision physics with heavy particles, but the electrons and positrons interact at low rate. Due to the superconducting acceleration the bunches are packed into 1 ms long trains interrupted by long empty periods of 199ms. During the trains the bunches are separated by 0.3μs. By using these features in the electronic design the system can be kept adequate and at some stages simple. From the electronics it is requested to follow the fast bunch-to-bunch structure (0.3μs) and even provide faster pulse analysis for signals, for which time information improves the energy measurement. But fast signals appear only during the trains 0.5% of the time. For the rest of the time the fast electronics is not needed. The data aquisition system can take the low occupancy and the long breaks between the trains as opportunity to minimize the infrastructure inside the detector. The physics of e+e−-collisions on the TeV-scale also defines requirements for the design of the detector. To reach the aim for high precision measurements of the properties of the heavy particles new concepts and technologies have to be developed. As case study the decay chain of heavy particles into vector bosons and further into jets is used to formulate the detector requirements. t,H→ Z,W→ leptons or jets The detector design aims for distinguishing the involved vector boson by reconstruction of its mass even from the jets. This needs tracking, vertex detection and a high energy resolution even for jets: