Speaker
Description
We present the polarization measurement of the $\Xi^-$ baryon produced in the $^{12}C(K^-,K^+)\Xi^-$ reaction and in the $p(K^-,K^+)\Xi^-$ reaction at the center-of-mass energy $\sqrt s=2.15$ GeV/c$^2$. We have collected 300k $^{12}C(K^-,K^+)\Xi^-$ events and reconstructed 30k $\Xi^-$ with a 1.8 GeV/c $K^-$ beam in J-PARC E42.
The polarization analysis of the $^{12}C$ dataset will provide informations about the spin state of the $\Xi$ baryon, which is necessary for the spin-state analysis in the search for H-dibaryon production. Using a CH$_2$ target, we reconstructed approximately 1k $\Xi^-$ in the $p(K^-,K^+)\Xi^-$ reaction. The polarization analysis of this dataset allows us to investigate the spin structure of a forward bump structure observed in the double strangeness reaction.
