Double Spin Asymmetries A_NN and A_SS at sqrt{s}=200 GeV in Polarized Proton-Proton Elastic Scattering at RHIC

pp2pp Collaboration; Bultmann, S.; Chiang, I. H.; Chrien, R. E.; Drees, A.; Gill, R. L.; Guryn, W.; Landgraf, J.; Ljubicic, T. A.; Lynn, D.; Pearson, C.; Pile, P.; Rusek, A.; Sakitt, M.; Tepikian, S.; Yip, K.; Chwastowski, J.; Pawlik, B.; Haguenauer, M.; Bogdanov, A. A.; Nurushev, S. B.; Runtzo, M. F.; Strikhanov, M. N.; Alekseev, I. G.; Kanavets, V. P.; Koroleva, L. I.; Morozov, B. V.; Svirida, D. N.; Khodinov, A.; Rijssenbeek, M.; Whitehead, L.; Yeung, S.; De, K.; Guler, N.; Li, J.; Ozturk, N.; Sandacz, A.

Double Spin Asymmetries A_NN and A_SS at sqrt{s}=200 GeV in Polarized Proton-Proton Elastic Scattering at RHIC

Authors

Description

We present the first measurements of the double spin asymmetries A_NN and A_SS at sqrt{s}=200 GeV, obtained by the pp2pp experiment using polarized proton beams at the Relativistic Heavy Ion Collider (RHIC). The data were collected in the four momentum transfer t range 0.01<|t|<0.03 (GeV/c)^2. The measured asymmetries, which are consistent with zero, allow us to estimate upper limits on the double helicity-flip amplitudes phi_2 and phi_4 at small t as well as on the difference Delta(sigma_T) between the total cross sections for transversely polarized protons with antiparallel or parallel spin orientations.
13 pages with 3 figures. Final version accepted by Phys. Lett. B