Cross section and transverse single-spin asymmetry of η mesons in p↑+p collisions at s =200GeV at forward rapidity

We present a measurement of the cross section and transverse single-spin asymmetry (AN) for. mesons at large pseudorapidityfrom root s = 200 GeV p up arrow+ p collisions. The measured cross section for 0.5 = 0.061 +/- 0.014. The results are consistent with prior transverse single-spin measurements of forward eta and pi(0) mesons at various energies in overlapping x(F) ranges. Comparison of different particle species can help to determine the origin of the large observed asymmetries in p up arrow+ p collisions.