Luo Y, Xu D, Blaskiewicz M, Montag C
Brookhaven National Laboratory, Upton, New York 11973, USA.
Phys Rev Lett. 2024 May 17;132(20):205001. doi: 10.1103/PhysRevLett.132.205001.
The Electron-Ion Collider (EIC), to be constructed at Brookhaven National Laboratory, will collide polarized high-energy electron beams with hadron beams, achieving luminosities of up to 1.0×10^{34} cm^{-2} s^{-1} in the center-of-mass energy range of 20-140 GeV. To achieve such high luminosity, the EIC will employ small and flat beams at the interaction point. In the hadron storage ring of the EIC, the ratio of horizontal to vertical emittances is approximately 11∶1. In contrast, in previous or existing hadron colliders, the horizontal and vertical emittances are typically similar or closely matched. At the Relativistic Heavy Ion Collider (RHIC), we experimentally demonstrated a large transverse emittance ratio of 11∶1 with gold ion beams at a particle energy of 100 GeV per nucleon, thanks to stochastic cooling and fine decoupling. Furthermore, we demonstrated collisions with flat beams, featuring a transverse beam size ratio of 3∶1 for the first time at the RHIC.
将在布鲁克海文国家实验室建造的电子-离子对撞机（EIC），会使极化的高能电子束与强子束对撞，在质心能量范围为20 - 140 GeV时实现高达1.0×10³⁴ cm⁻² s⁻¹ 的亮度。为实现如此高的亮度，EIC将在相互作用点采用小而扁平的束流。在EIC的强子储存环中，水平发射度与垂直发射度之比约为11∶1。相比之下，在以往或现有的强子对撞机中，水平和垂直发射度通常相似或紧密匹配。在相对论重离子对撞机（RHIC）上，由于随机冷却和精细解耦，我们在每个核子100 GeV的粒子能量下，用金离子束实验证明了11∶1的大横向发射度比。此外，我们在RHIC首次展示了具有3∶1横向束流尺寸比的扁平束流对撞。
