K*(892)+ production in proton-proton collisions at E_beam = 3.5 GeV

TL;DR

This paper reports the first observation of K*(892)+ meson production in proton-proton collisions at 3.5 GeV, providing new data on its production cross section and characteristics at low energies.

Contribution

It presents the lowest-energy measurement of K*(892)+ production in nucleon-nucleon reactions and interprets the data within a two-channel model including hyperon-associated production.

Findings

Total cross section measured as 9.5 ± 0.9 +1.1 -0.9 ± 0.7 mub

Provides transverse momentum and angular spectra at low energies

Discusses spin alignment of K*(892)+

Abstract

We present results on the K*(892)+ production in proton-proton collisions at a beam energy of E = 3.5 GeV, which is hitherto the lowest energy at which this mesonic resonance has been observed in nucleon-nucleon reactions. The data are interpreted within a two-channel model that includes the 3-body production of K*(892)+ associated with the Lambda- or Sigma-hyperon. The relative contributions of both channels are estimated. Besides the total cross section sigma(p+p -> K*(892)+ + X) = 9.5 +- 0.9 +1.1 -0.9 +- 0.7 mub, that adds a new data point to the excitation function of the K*(892)+ production in the region of low excess energy, transverse momenta and angular spectra are extracted and compared with the predictions of the two-channel model. The spin characteristics of K*(892)+ are discussed as well in terms of the spin-alignment.