Is It Possible to Study the Wave Function of 2S Vector Mesons at HERA ?

Abstract

We present a short review of anomalous properties in diffractive photo- and electroproduction of radially excited V'(2S) vector mesons. Using the color dipole gBFKL phenomenology we analyze anomalous Q^{2} and energy dependence of the production cross section, V'(2S)/V(1S) production ratio, the diffraction slope and anomalous t behaviour of the differential cross section d\sigma/dt. The origin of these anomalies is based on the interplay of the nodal structure of V'(2S) radial wave function with the energy and dipole size dependence of the dipole cross section and the diffraction slope. We analyze how a different pattern of anomalous behaviour of V'(2S) production leads to a different position of the node in the wave function and discuss how that node position can be extracted from the data at HERA.