Model to study interplay between Beamstrahlung and coupling impedance in future lepton colliders

Beamstrahlung-enhanced disruption in beam-beam interaction

The radiation reaction (beamstrahlung) effect on particle dynamics during interaction of oppositely charged beams is studied. It is shown that the beam focusing can be strongly enhanced due to beamstrahlung. An approximate analytical solution of the motion equation including the radiation reaction force is derived. The disruption parameter is calculated for classical and quantum regime of beamstrahlung. The analytical model is verified by QED-PIC simulations. The model for head-on collision of long beams undergoing a number of betatron oscillation during interaction is also developed. It is de…

束流辐射量子极限下强场量子电动力学的信号

Signatures for strong-field QED in the quantum limit of beamstrahlung

本文研究了束流辐射量子极限下超相对论性轻子束碰撞中的强场QED信号，推导了具有特征峰的积分束流辐射光子谱，并指出其能产生峰值亮度极高的超短准直伽马射线束。

Challenges for the interaction region design of the Future Circular Collider FCC-ee

The FCC-ee is a proposed future high-energy, high-intensity and high-precision lepton collider. Here, we present the latest development for the FCC-ee interaction regions, which shall ensure optimum conditions for the particle physics experiments. We discuss measures of background reduction and a revised interaction region layout including a low impedance compact beam chamber design. We also discuss the possible impact of the radiation generated in the interaction region including beamstrahlung.

Strong field effects on physics processes at the Interaction Point of future linear colliders

Future lepton colliders will be precision machines whose physics program includes close study of the Higgs sector and searches for new physics via polarised beams. The luminosity requirements of such machines entail very intense lepton bunches at the interaction point with associated strong electromagnetic fields. These strong fields not only lead to obvious phenomena such as beamstrahlung, but also potentially affect every particle physics process via virtual exchange with the bunch fields. For precision studies, strong field effects have to be understood to the sub-percent level. Strong exte…

Beam-beam Blowup in the presence of x-y coupling sources at FCC-ee

FCC-ee, the lepton version of the Future Circular Collider (FCC), is a 100 Km future machine under study to be built at CERN. It acquires two experiments with a highest beam energy of 182.5 GeV. FCC-ee aims to operate at four different energies, with different luminosities to fulfil physics requirements. Beam-beam effects at such a high energy/luminosity machine are very challenging and require a deep understanding, especially in the presence of x-y coupling sources. Beam-beam effects include the beamstrahlung process, which limits the beam lifetime at high energies, as well as dynamic effects…

Xsuite：一个集成的束流物理仿真框架

Xsuite: an integrated beam physics simulation framework

本文介绍Xsuite模块化束流物理仿真框架，整合CERN多款工具，支持多物理效应、准直仿真、光学计算及CPU/GPU平台。