Photoproduction ofZ(4430)through mesonic Regge trajectories exchange

Abstract

The recently discovered Z(4430) mesonic resonance is believed to be a strong tetraquark candidate. The photoproduction in the channel γp → Z + (4430)n → ψ π + n has been proposed as the most effective way to confirm the Z(4430) presence and to measure its quantum numbers. In this work we present a model for high energy and forward angle Z(4430) photoproduction in a effective Lagrangian approach. This model is based on the use of Regge trajectories exchange, thus a Regge propagator replaces the usual Feynman propagator. The differential and total cross sections and the asymmetries have been calculated for the J P quantum numbers 1 − , 1 + , 0 − and 2 − in the hypotheses that Z(4430) has isospin I = 1.

The hidden-charm pentaquark and tetraquark states

“…This process was further studied in Ref. [527], where Galata presented a model for high energy and forward angle Z + (4430) photoproduction in an effective Lagrangian approach.…”

Production of the neutralZ0(4430)inp¯p→ψ<

“…For example, Liu et al proposed the production of the Z± (4430) state by the process of yp -» Z+ (4430)« -► y/'n+n [13], while Galate suggested searching for the Z± (4430) state by the meson photoproduction process through mesonic Regge trajectories exchange [14], Unfortunately, studies of the production mechanism of the neutral Z°(4430) state still have not produced relevant results in either theory and experimentation. Similar to the observation of the neutral partners Zc(3900) and Zc(4020), neutral Z°(3900) and Z^(4020) have been reported by CLEO-c [15] and BESIII [16], respectively.…”

“…■ ~/ a + <&<&<& q] -m z + iMzr z (14) In addition, because of the size of the hadrons, we take the general form factor for the off-shell Z°(4430) state as it is used in Refs. [27][28][29],…”

Photoproduction of charged final states in ultraperipheral collisions and electroproduction at an electron-ion collider

“…For the a + 2 (1320), we added a Reggeon-inspired parameterization of cross-section data from fixed-target photoproduction experiments, while for the Z + c (4430), we used a theoretical prediction which assumes that the Z + c is a tetraquark with a J P = 1 + states. The Z + c (4430) photoproduction cross-section is calculated in a Reggeon exchange model [14]. The photoproduction cross-section is sensitive to the Z + c (4430) spin and parity; J P = 1 − leads to a 40% larger crosssection, while J P = 0 − leads to a cross-section about three times larger at the peak, with the ratio increasing at larger photon energies.…”

“…We model Z + c (4430) photoproduction following the Reggeon-model calculation in Ref. [14]. Numerically, we use a 4-parameter fit to the J P = 1 + curve in Ref.…”