Experiments to measure the electric and the magnetic moments of short-lived baryons using an internal target and two bent crystals in the vicinity of one of the existing LHC detectors were recently proposed, in the frame of the Physics Beyond Colliders Working Group at CERN. Investigating fixed-target physics in the LHC with in-vacuum solid targets is an unprecedented challenge. As a preparatory step, the layout of the UA9 experiment, installed in the CERN SPS to explore beam manipulations assisted by bent crystals, has been modified to study the feasibility of the double-crystal scenario in a circular accelerator. Ideally, the first crystal should capture halo protons in channeling states directing them onto the internal target to produce rare baryons, whilst the second crystal, located just downstream of the target, should channel the baryons, rotate their polarization vector and deflect them towards the detector area. The upgraded UA9 layout is presented. Preliminary measurements providing an insight of the beam behavior are reported.

最近在CERN的“超越对撞机的物理学”工作组的框架内，提出了使用内部目标和两个弯曲晶体在一个现有LHC探测器附近测量短寿命重子的电和磁矩的实验。在大型强子对撞机中研究具有真空实心目标的固定目标物理是前所未有的挑战。作为准备步骤，已经修改了安装在CERN SPS中的UA9实验的布局，以探索由弯曲晶体辅助的光束操纵，以研究在圆形加速器中双晶体方案的可行性。理想情况下，第一个晶体应捕获处于通道状态的晕子质子，将其引导到内部靶标上以生成稀有的重子，而第二个晶体位于靶标的下游，应引导重子，旋转其偏振矢量并使它们偏向检测器区域。显示了升级后的UA9布局。报告了初步的测量结果，可以了解光束的行为。