Hardware-based track reconstruction in the CMS and ATLAS trigger systems for the High-Luminosity LHC upgrade will provide unique capabilities. An overview is presented of earlier track trigger systems at hadron colliders, in particular for the Tevatron CDF and D0 experiments. We discuss the plans of the CMS and ATLAS experiments to implement hardware-based track reconstruction for the High-Luminosity LHC. Particular focus is placed on the track trigger capability of the upgraded CMS experiment. We discuss the challenges and opportunities of this novel handle, and review the alternatives that were considered for its implementation as well as discuss the expected performance. The planned track trigger systems for CMS and ATLAS have different goals, and we compare and contrast the two approaches.

中文翻译：

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HL-LHC 的跟踪触发器

用于高亮度 LHC 升级的 CMS 和 ATLAS 触发系统中基于硬件的轨道重建将提供独特的功能。概述了早期的强子对撞机轨道触发系统，特别是 Tevatron CDF 和 D0 实验。我们讨论了 CMS 和 ATLAS 实验的计划，以实现高亮度 LHC 的基于硬件的轨道重建。特别关注升级后的 CMS 实验的跟踪触发能力。我们讨论了这种新颖手柄的挑战和机遇，并审查了为其实施考虑的替代方案，并讨论了预期性能。CMS 和 ATLAS 的计划轨道触发系统有不同的目标，我们比较和对比这两种方法。