Conventional CCD detectors have two major disadvantages: they are slow to read out and they suffer from read noise. These problems combine to make high-speed spectroscopy of faint targets the most demanding of astronomical observations. It is possible to overcome these weaknesses by using electron-multiplying CCDs (EMCCDs). EMCCDs are conventional frame-transfer CCDs, but with an extended serial register containing high-voltage electrodes. An avalanche of secondary electrons is produced as the photon-generated electrons are clocked through this register, resulting in signal amplification that renders the read noise negligible. Using a combination of laboratory measurements with the QUCAM2 EMCCD camera and Monte Carlo modelling, we show that it is possible to significantly increase the signal-to-noise ratio of an observation by using an EMCCD, but only if it is optimised and utilised correctly. We also show that even greater gains are possible through the use of photon counting. We present a recipe for astronomers to follow when setting up a typical EMCCD observation which ensures that maximum signal-to-noise ratio is obtained. We also discuss the benefits that EMCCDs would bring if used with the next generation of extremely large telescopes. Although we mainly consider the spectroscopic use of EMCCDs, our conclusions are equally applicable to imaging.
Characterization of Low Light Performance of a CMOS sensor for Ultraviolet Astronomical Applications
CMOS探测器在光学和紫外天文应用中具有许多优于CCD的优势，特别是在需要高辐射耐受性的空间中。然而，天文仪器通常设计用于低亮度观测，要求低暗电流和读取噪声，良好的线性度和高动态范围，这些特性尚未在CMOS成像器中得到广泛证明。我们报告的性能，从140 - 240 K，辐射硬化SRI 4Kx 2K背照式CMOS图像传感器的表面处理，使其在蓝色和紫外波段高度敏感的温度。在抑制发光点的发射后，在这项工作中检查的工程级设备中的缺陷，在160 K时达到0.077 me-/s的暗电流地板，上升到1 me $^-$ /s在184 K，媲美最好的CCD。我们检查读出速度和读取噪声之间的权衡，发现1.43 e $^-$中值读取噪声是使用对应于1.5 s读出时间的700 kpix/s/ch的逐行数字相关双采样实现的。高增益模式下的15 ke $^-$阱容量扩展到双增益模式下的120 ke $^-$。在读出期间持续收集光生电荷使得能够通过组合短曝光和长曝光而在曝光效率仅损失1%的情况下进一步扩展超过$10^6$ e $^-$有效阱容量的动态范围。校正非线性的二次拟合将增益校正残差从1.5%降低到0.2%（低增益模式）和0.4%（高增益模式）。与相邻像素的串扰垂直仅为0.4%，水平为0.6%，对角为0.1%。这些特性加上相对较大的10 $μ$ m像素尺寸、准4面对接能力、电子快门和子阵列读出使该传感器成…
Performance Calibration of the Wavefront Sensor's EMCCD Detector for the Cool Planets Imaging Coronagraph Aboard CSST
Nanjing Institute of Astronomical Optics & Technology, Chinese Academy of Sciences（中国科学院南京天文光学技术研究所）；CAS Key Laboratory of Astronomical Optics & Technology, Nanjing Institute of Astronomical Optics & Technology（中国科学院天文光学与技术重点实验室，中国科学院南京天文光学技术研究所）；University of Chinese Academy of Sciences（中国科学院大学）
Output-Stage Design Optimization for High-Sensitivity SiSeRO CCDs and SiSeRO Active Pixel Sensors
Kavli Institute of Astrophysics and Cosmology, Stanford University（斯坦福大学天体物理与宇宙学 Kavli 研究所）；MIT Lincoln Laboratory（麻省理工学院林肯实验室）；Department of Physics, Stanford University（斯坦福大学物理系）；SLAC National Accelerator Laboratory（SLAC国家加速器实验室）；Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology（麻省理工学院天体物理与空间研究 Kavli 研究所）
Advancing Ultraviolet Detector Technology for future missions: Investigating the dark current plateau in silicon detectors using photon-counting EMCCDs
Characterization of the Cherenkov Photon Background for Low-Noise Silicon Detectors in Space
University of Chicago（芝加哥大学）；Fermi National Accelerator Laboratory（费米国家加速器实验室）；NSF-Simons AI Institute for the Sky (SkAI)（NSF-西蒙斯天空人工智能研究所）；NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）
Optimal Photon Counting with Fast, Low Noise Astronomical Imagers
Stanford University（斯坦福大学）；Kavli Institute for Particle Astrophysics and Cosmology, Stanford University（斯坦福大学粒子天体物理与宇宙学 Kavli 研究所）；Massachusetts Institute of Technology（麻省理工学院）；Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology（麻省理工学院天体物理与空间研究 Kavli 研究所）；The Observatories of the Carnegie Institution for Science（卡内基科学机构天文台）
