Transverse single spin asymmetry for very forward $\ddot{I}{€}^0$ production in polarized proton-proton collisions at $\sqrt{s}$ = 510 GeV

Abstract

Transverse single spin asymmetry, $A_N$, of very forward $\ddot{I}{€}^0$ production from polarized $p+p$ collisions provides new information toward an understanding of its production mechanism. $A_N$ of forward $\ddot{I}{€}^0$ in the pseudorapidity region of $3<\hat{I}\cdot <4$ has been described by the partonic structure of the proton in the perturbative QCD framework. However, recent data indicates a potential contribution from not only partonic but also diffractive interactions. In order to provide a new insight on the origin of the $A_N$, we measured the very forward $\ddot{I}{€}^0$ production in the pseudorapidity region of $6<\hat{I}\cdot$ from $\sqrt{s}$ = 510 GeV polarized $p+p$ collisions at RHIC in 2017. We report our measurement of the very forward $\ddot{I}{€}^0$ over the transverse momentum range of $0<p_T<1$ GeV/$c$ and the preliminary result.

This paper was first presented for a proceeding of ISVHECRI 2018