Alekseev, I.G
P P --> P P
Polarization
Max results
Sort by Reverse order

Showing 3 of 3 results

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

The pp2pp collaboration Bultmann, S. ; Chiang, I.H. ; Chrien, R.E. ; et al.
Phys.Lett.B 647 (2007) 98-103, 2007.
Inspire Record 729168 DOI 10.17182/hepdata.31499

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.

3 data tables match query
Table 1

Double spin asymmetries.

Table 2

Double spin asymmetries.

Table 3

T dependence of the double spin asymmetry ASS3 with statistical errors only.


Measurement of the analyzing power A(N) in p p elastic scattering in the CNI region with a polarized atomic hydrogen gas jet target.

Okada, H. ; Alekseev, I.G. ; Bravar, A. ; et al.
2006.
Inspire Record 707803 DOI 10.17182/hepdata.41834

A precise measurement of the analyzing power $A_N$ in proton-proton elastic scattering in the region of 4-momentum transfer squared $0.001 < |t| < 0.032 ({\rm GeV}/c)^2$ has been performed using a polarized atomic hydrogen gas jet target and the 100 GeV/$c$ RHIC proton beam. The interference of the electromagnetic spin-flip amplitude with a hadronic spin-nonflip amplitude is predicted to generate a significant $A_N$ of 4--5%, peaking at $-t \simeq 0.003 ({\rm GeV}/c)^2$. This kinematic region is known as the Coulomb Nuclear Interference region. A possible hadronic spin-flip amplitude modifies this otherwise calculable prediction. Our data are well described by the CNI prediction with the electromagnetic spin-flip alone and do not support the presence of a large hadronic spin-flip amplitude.

1 data table match query
Table 1

Analysing power as a function of momentum transfer T. The first DSYS error is the systematic error, the second is the normalization error on the target polarization.


First measurement of A(N) at s**(1/2) = 200-GeV in polarized proton proton elastic scattering at RHIC.

Bultmann, S. ; Chiang, I.H. ; Chrien, R.E. ; et al.
Phys.Lett.B 632 (2006) 167-172, 2006.
Inspire Record 688172 DOI 10.17182/hepdata.31570

We report on the first measurement of the single spin analyzing power (A_N) at sqrt(s)=200GeV, obtained by the pp2pp experiment using polarized proton beams at the Relativistic Heavy Ion Collider (RHIC). Data points were measured in the four momentum transfer t range 0.01 < |t| < 0.03 (GeV/c)^2. Our result, averaged over the whole t-interval is about one standard deviation above the calculation, which uses interference between electromagnetic spin-flip amplitude and hadronic non-flip amplitude, the source of A_N. The difference could be explained by an additional contribution of a hadronic spin-flip amplitude to A_N.

1 data table match query
Table 1

The single spin analyzing power for 3 T intervals.