Studies of possible energy upgrades of the Large Hadron Collider (LHC) aim at increasing the current nominal beam energy of 7 TeV in view of expanding the discovery potential and physics reach of the LHC. Some critical aspects of the feasibility of partial or full energy upgrades are studied here, together with novel mitigation measures. Higher beam energies can be realized by pushing the installed main dipoles to their limits or by replacing different fractions of installed magnets. Moreover, a revised lattice design for a full energy upgrade, also known as the high-energy LHC (HE-LHC), is presented. The studies reported focus on the linear optics design and on the lattice layout. In particular, an optics with 60° transverse phase advance in the regular arc cells, meant to alleviate the strength requirements for the main quadrupoles, has been designed in view of possible beam tests during the next LHC run 3. The methods developed in this article, for matching the ring geometry to a reference tunnel, for improving the beam aperture, and for minimizing the required field strengths for new high-energy LHC-like machines, will also be applicable to other future circular collider projects.

中文翻译：

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晶格和光学选项可用于大型强子对撞机的能源升级

大型强子对撞机（LHC）可能进行的能量升级研究旨在扩大LHC的发现潜力和物理范围，从而将当前的标称束能量提高到7 TeV。这里研究了部分或全部能源升级的可行性的一些关键方面，以及新颖的缓解措施。通过将已安装的主偶极子推至极限位置或更换不同比例的已安装磁体，可以实现更高的束能量。此外，还提出了用于全面能源升级的改进型晶格设计，也称为高能LHC（HE-LHC）。研究报告指出，重点放在线性光学设计和晶格布局上。尤其是，在规则弧形单元中具有60°横向相位的光学器件可以减轻主要四极杆的强度要求，