Single transverse spin asymmetry for the very forward neutral pion production

초록

We investigate the single transverse spin asymmetry for the forward neutral pion production using the interferences between proton, \Delta(1232) and N^*(1535) Reggeon exchanges. The Born amplitudes for the p+p^\uparrow \to \pi^0 + X are expressed in terms of the hybridized Regge propagator and inclusive proton-baryon processes A_{pB\to X}. Since they are experimentally not known yet, one parametrize A_{p\Delta\to X} and A_{pN^*\to X} as fitting parameters. We presented the numerical results for A_N as functions of p_T and x_F. The results describe very well recent experimenal data from the RHICf Collaboration. The present study indicates that in the low p_T region A_N is governed by diffractive processes.