Characterisation and testing of CHEC-M-A camera prototype for the small-sized telescopes of the Cherenkov telescope array
Characterisation and testing of CHEC-M-A camera prototype for the small-sized telescopes of the Cherenkov telescope array
复制标题
用于切伦科夫望远镜阵列小型望远镜的 CHEC-M-A 相机原型的表征和测试
DOI：
10.1016/j.nima.2018.06.078
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Zorn J
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文献类型：
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作者：
Zorn J
摘要紧凑型高能相机（CHEC）是切伦科夫望远镜阵列（CTA）小型望远镜（SST; 4 m直径镜）的相机设计。SST的重点是通过大气切伦科夫光探测在非常大的区域内进行非常高能量的γ射线探测。这意味着许多单独的单元以及因此具有成本效益的实施方式，以及在大的撞击距离处的淋浴检测，以及因此大的视场（FoV），以及在由相机检测到的淋浴图像中存在大的时间梯度的情况下的有效图像捕获。CHEC依靠双反射镜光学器件来减小板尺度并利用6× 6 mm 2像素，从而产生低成本（150 k€）、紧凑（0.5 m× 0.5 m）和轻（145 kg）的相机，具有2048像素，提供149度的相机FoV。CHEC电子器件基于定制的TARGET（具有GSa/s采样和事件触发的TeV阵列读出）专用集成电路（ASIC）和现场可编程门阵列（FPGA），以每秒千兆采样的速度对输入信号进行采样，并在单个背板FPGA内实现灵活的相机级触发。CHEC的设计目的是在1-300 TeV的γ射线能量范围内进行观测，撞击距离可达1500米。为了适应这一点，并提供充分的灵活性，为以后的数据分析，96个样本的所有2048个像素的完整波形可以读出的速率高达10900赫兹。第一个原型，MAP-M，基于多阳极光电倍增管（MAPM）作为光电传感器，在实验室和两次测量活动期间在默东的巴黎天文台的望远镜结构上进行了委托和表征。本文介绍了试验室和现场试验的结果和结论。他们为这类照相机的系统设计和操作及数据分析程序提供了重要的投入。第二个基于硅光电倍增管（SiPM）的全相机原型已经建成，目前正在实验室进行调试和测试，以解决在第一个原型阶段发现的U-M的缺点。
Abstract The Compact High Energy Camera (CHEC) is a camera design for the Small-Sized Telescopes (SSTs; 4 m diameter mirror) of the Cherenkov Telescope Array (CTA). The SSTs are focused on very-high-energy γ-ray detection via atmospheric Cherenkov light detection over a very large area. This implies many individual units and hence cost-effective implementation, as well as shower detection at large impact distance, and hence large field of view (FoV), and efficient image capture in the presence of large time gradients in the shower image detected by the camera. CHEC relies on dual-mirror optics to reduce the plate-scale and make use of 6× 6 mm 2 pixels, leading to a low-cost (∼ 150 k€), compact (0.5 m× 0.5 m), and light (∼ 45 kg) camera with 2048 pixels providing a camera FoV of∼ 9 degrees. The CHEC electronics are based on custom TARGET (TeV array readout with GSa/s sampling and event trigger) application-specific integrated circuits (ASICs) and field programmable gate arrays (FPGAs) sampling incoming signals at a gigasample per second, with flexible camera-level triggering within a single backplane FPGA. CHEC is designed to observe in the γ-ray energy range of 1–300 TeV, and at impact distances up to∼ 500 m. To accommodate this and provide full flexibility for later data analysis, full waveforms with 96 samples for all 2048 pixels can be read out at rates up to∼ 900 Hz. The first prototype, CHEC-M, based on multi-anode photomultipliers (MAPMs) as photosensors, was commissioned and characterised in the laboratory and during two measurement campaigns on a telescope structure at the Paris Observatory in Meudon. In this paper, the results and conclusions from the laboratory and on-site testing of CHEC-M are presented. They have provided essential input on the system design and on operational and data analysis procedures for a camera of this type. A second full-camera prototype based on Silicon photomultipliers (SiPMs), addressing the drawbacks of CHEC-M identified during the first prototype phase, has already been built and is currently being commissioned and tested in the laboratory.