论文标题
偶极大小波动对媒介介子衍射产生的影响
Effect of dipole size fluctuations on diffractive photo-production of vector mesons
论文作者
论文摘要
我们考虑偶极模型中质子上媒介中介子的衍射照片产生。我们考虑了偶极子大小波动的影响，偶极子大小的大小由光子和矢量介子波函数之间的重叠控制。我们对在冲击参数饱和模型（IPSAT）中获得的非相干衍射横截面的预测与HERA数据非常吻合，符合$ j/ψ$照相产生的HERA数据，直至非常低的动量传递，其中偶极大小的波动显示出起着重要作用。这项研究通过添加另一个``几何''波动的来源，即在质子形状的波动方面对不连贯的衍射过程的任何其他参数进行补充，即从光子将光子散布到各种尺寸的色素中。
We consider the diffractive photo-production of vector mesons on a proton, in the dipole model. We take into account the effect of the fluctuations of the the dipole size, whose magnitude is controlled by the overlap between the photon and the vector meson wave functions. Our predictions for the incoherent diffractive cross section, obtained within the Impact Parameter Saturation Model (IPSat), are shown to be in excellent agreement with the HERA data on $J/Ψ$ photo-production, down to very low momentum transfer, where the dipole size fluctuations are shown to play an essential role. This study complements, without introducing any additional parameter, previous treatments of incoherent diffractive processes in terms of fluctuations of the proton shape, by adding another source of ``geometrical'' fluctuations, namely those coming from the splitting of the photon into color dipoles of various sizes.
