Speaker
Description
The GlueX experiment at Jefferson Lab has collected an unprecedented amount of data and will continue to do so on the production of light mesons with a polarized photon beam. These data can provide detailed insights into the photoproduction mechanisms, but their interpretation requires a parallel theoretical effort. In the high energy regime studied by GlueX, the photoproduction of single mesons can be explained in terms of Regge exchanges. Although it is well known that pion exchange dominates at low momentum transfer in charge-exchange reactions, the precise determination of its contribution in high energy peripheral production has never been satisfactorily established. The high precision data from photoproduction reactions at GlueX will certainly help in this regard. In this talk I will focus on the pion photoproduction reaction, which offers a clean probe of the pion exchange mechanism. I will discuss the role of gauge invariance in pion exchange, relevant to approach its reggeization in an appropriate way. I will also present a novel strategy to reggeize the pion pole which considers explicitly the exchange in the t-channel of all the mesons in the pion trajectory. Each of these exchanges contributes with a pole in spin, known as a Regge pole. I will demonstrate that the summation of these poles can be performed analytically, and I will compare the outcomes of this approach with other commonly used reggeization prescriptions [1].
[1] G. Montana, et al. (JPAC Collaboration) (in preparation)
