Hencken Kai, Baur Gerhard, Trautmann Dirk
Institut für Physik, Universität Basel, 4056 Basel, Switzerland.
Phys Rev Lett. 2006 Jan 13;96(1):012303. doi: 10.1103/PhysRevLett.96.012303. Epub 2006 Jan 10.
We study the transverse momentum distribution of vector mesons produced in ultraperipheral relativistic heavy ion collisions (UPCs). In UPCs there is no strong interaction between the nuclei, and the vector mesons are produced in photon-nucleus collisions where the (quasireal) photon is emitted from the other nucleus. Exchanging the role of both ions leads to interference effects. A detailed study of the transverse momentum distribution, which is determined by the transverse momentum of the emitted photon, the production process on the target, and the interference effect, is done. We study the unrestricted cross section and the one with an additional electromagnetic excitation of one or both ions; in the latter case small impact parameters are emphasized.
我们研究了超外围相对论重离子碰撞（UPCs）中产生的矢量介子的横向动量分布。在UPCs中，原子核之间不存在强相互作用，矢量介子是在光子 - 原子核碰撞中产生的，其中（准实）光子从另一个原子核发射。交换两个离子的角色会导致干涉效应。我们对由发射光子的横向动量、靶上的产生过程以及干涉效应所决定的横向动量分布进行了详细研究。我们研究了无限制截面以及对一个或两个离子进行额外电磁激发的截面；在后一种情况下，强调了小碰撞参数。
