Xi(1690)(-) production in the K(-)p -> K+K- reaction process near threshold

Abstract

We investigate Xi(1690)(-) production from the K(-)p -> K+K-Lambda reaction within the effective Lagrangian approach at the tree-level Born approximation. We consider the s- and u-channel Sigma/A ground states and resonances for the Xi-pole contributions, in addition to the s-channel A, u -channel nucleon pole, and t-channel K- exchange for the phi-pole contributions. The Xi, pole includes Xi(1320), Xi(1535), Xi(1690) (J(P) = 1/2(-)), and Xi(1820)(J(p) = 3/2(-)). We calculate the Dalitz plot density of (d(2)sigma/dM(K)+(K)-dM(K-Lambda) at 4.2 GeV/c) and the total cross sections for the K(-)p -> K+K-Lambda reaction near the threshold. The calculation results are in good agreement with previously acquired experimental data. Using the parameters from the fit, we present the total and differential cross sections for the two-body K(-)p -> K+Xi(1690)(-) reaction near the threshold. In our calculation, a strong enhancement at backward K+ angles is predicted because of the dominant u-channel contribution. We also demonstrate that the Dalitz plot analysis for p(K)- = 1.915-2.065 GeV/c enables us to access direct information regarding a. (1690)-production, which can be tested by future K-beam experiments. The possible spin -parity states of Xi (1690)(-) are briefly discussed as well.