The ATLAS physics program at the High Luminosity LHC (HL-LHC) calls for a precision in the luminosity measurement of 1%. A larger uncertainty would represent the dominant systematic error in precision measurements, including those in the Higgs sector. To fulfill such requirement in an environment characterized by up to 140 simultaneous interactions per crossing (200 in the ultimate scenario), ATLAS will feature several luminosity detectors. At least some of them must be both calibratable in the van der Meer scans at low luminosity and able to measure up to the highest values. LUCID-3, the upgrade of the present ATLAS luminometer (LUCID-2), will fulfill such a condition. The reasons for an upgrade of LUCID-2 and the envisaged solutions are discussed and a description of the LUCID-3 project is given. Finally, the first results obtained with the prototypes installed in ATLAS during the present LHC Run-3 are discussed as means of the validation of the final design.

中文翻译：

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LUCID-3：高光度大型强子对撞机ATLAS光度探测器的升级版

高光度大型强子对撞机 (HL-LHC) 的 ATLAS 物理项目要求光度测量精度达到 1%。更大的不确定性将代表精密测量中的主要系统误差，包括希格斯扇区的测量。为了在每次交叉最多 140 个同时交互（最终场景中为 200 个）的环境中满足此类要求，ATLAS 将配备多个光度探测器。至少其中一些必须能够在低光度的范德米尔扫描中进行校准，并且能够测量到最高值。 LUCID-3是现有ATLAS光度计（LUCID-2）的升级版，将满足这样的条件。讨论了 LUCID-2 升级的原因和设想的解决方案，并给出了 LUCID-3 项目的描述。最后，讨论了当前 LHC Run-3 期间安装在 ATLAS 中的原型获得的初步结果，作为验证最终设计的手段。