## The Beam-Helicity Asymmetry for Two Pseudoscalar Mesons in Photoproduction and a Partial Wave Analysis for Excited Hyperons Thesis

(2016). The Beam-Helicity Asymmetry for Two Pseudoscalar Mesons in Photoproduction and a Partial Wave Analysis for Excited Hyperons . 10.25148/etd.FIDC000736

### abstract

• The first-time measurement of the angular dependence of the beam-helicity asymmetry for $\gamma p \rightarrow pK^{+}K^{-}$ is shown and compared to $\gamma p \rightarrow p\pi^{+}\pi^{-}$. The data obtained were from the CLAS g12 experiment at Jefferson Lab. The experiment utilized a beam of circularly polarized photons with energies between 1.1 and 5.4 GeV incident on an unpolarized liquid hydrogen target, which produced an unprecedented number of strange hadrons in photoproduction. The production mechanism for strange hadrons is not well understood. The beam-helicity asymmetry is a polarization observable that provides information on interfering production mechanisms in the reaction. It is shown that the asymmetry is sensitive to several kinematic variables that are key in modeling the reaction dynamics. Furthermore, the comparison of the beam-helicity asymmetry between the kaon and pion channels serves as a platform for the investigation of flavor dependence. A partial wave analysis on the $pK^{-}$ system is also performed in a search for missing hyperon excitations.

### publication date

• June 24, 2016

### keywords

• CLAS
• Jefferson lab
• baryon spectroscopy