Alekseev, I.
P P --> P P
POL.POL
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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
Table 1

Double spin asymmetries.

Table 2

Double spin asymmetries.

Table 3

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


The Acceleration of Polarized Protons to 22-{GeV}/$c$ and the Measurement of Spin Spin Effects in $p$ (Polarized) + $p$ (Polarized) $\to p + p$

Khiari, F.Z. ; Cameron, P.R. ; Court, G.R. ; et al.
Phys.Rev.D 39 (1989) 45, 1989.
Inspire Record 262472 DOI 10.17182/hepdata.23245

Accelerating polarized protons to 22 GeV/c at the Brookhaven Alternating Gradient Synchro- tron required both extensive hardware modifications and a difficult commissioning process. We had to overcome 45 strong depolarizing resonances to maintain polarization up to 22 GeV/c in this strong-focusing synchrotron. At 18.5 GeV/c we measured the analyzing power A and the spin-spin correlation parameter Ann in large- P⊥2 proton-proton elastic scattering, using the polarized proton beam and a polarized proton target. We also obtained a high-precision measurement of A at P⊥2=0.3 (GeV/c)2 at 13.3 GeV/c. At 18.5 GeV/c we found that Ann=(-2±16)% at P⊥2=4.7 (GeV/c)2, where it was about 60% near 12 GeV at the Argonne Zero Gradient Synchrotron. This sharp change suggests that spin-spin forces may have a strong and unexpected energy dependence at high P⊥2.

3 data tables
Table 1

No description provided.

Table 2

2.2 GeV point taken from Brown et al., PR D31(85) 3017.

Table 3

No description provided.


Measurement of Spin Effects in $p$ (Polarized) $p$ (Polarized) $\to p p$ at 18.5-{GeV}/$c$

Crabb, D.G. ; Gialas, I. ; Krisch, A.D. ; et al.
Phys.Rev.Lett. 60 (1988) 2351, 1988.
Inspire Record 261135 DOI 10.17182/hepdata.20096

We measured the analyzing power A and the spin-spin correlation parameter Ann in medium-P⊥2 proton-proton elastic scattering, using a polarized-proton target and the 18.5-GeV/c Brookhaven Alternating-Gradient Synchrotron polarized-proton beam. We found sharp dips in both A and Ann, which occur at different P⊥2 values. The unexpected sharp structure in the spin-spin force occurs near P⊥2=2.3 (GeV/c)2 where the elastic cross section has no apparent structure.

1 data table
Table 1

Errors contain both statistics and systematics.


Energy Dependence of Spin Effects in $p$ (Polarized) $p$ (Polarized) $\to p p$

Court, G.R. ; Crabb, D.G. ; Gialas, I. ; et al.
Phys.Rev.Lett. 57 (1986) 507, 1986.
Inspire Record 229812 DOI 10.17182/hepdata.20190

We measured the analyzing power A and the spin-spin correlation parameter Ann, in large-P⊥2 proton-proton elastic scattering, using a polarized-proton target and the polarized-proton beam at the Brookhaven Alternating-Gradient Synchrotron. We also used our polarimeter to measure A at small P⊥2 at 13 GeV with good precision and found some deviation from the expected 1Plab behavior. At 18.5 GeV/c we found Ann=(−2±16)% at P⊥2=4.7 (GeV/c)2. Comparison with lower-energy data from the Argonne Zero-Gradient Synchrotron shows a sharp and surprising energy dependence for Ann at large P⊥2.

3 data tables
Table 1

POL is error weighted average of polarized beam and target measurements.

Table 2

POL is error-weighted average of polarized beam and target measurements.

Table 3

POL is error-weighted average of polarized beam and target measurement.


Measurements of the Spin Rotation Parameter R in p p and pi+ p Elastic Scattering at 45-GeV/c

The SERPUKHOV-SACLAY-DUBNA-MOSCOW collaboration Pierrard, J. ; Bruneton, C. ; Bystricky, J. ; et al.
Phys.Lett.B 61 (1976) 107-109, 1976.
Inspire Record 113035 DOI 10.17182/hepdata.27706

The spin rotation sf R in pp and π + p elastic scattering at 45 GeV/c has been measured at the Seppukhov accelarator, for z . sfnc ; t |; ranging from 0.2 to 0.5 (GeV/) 2 . The results are presented, together with previous R measurements at lower energies. The equality of the values for R in proton-proton and pion-proton scattering, within the experimental errors, is a test of factorization of the residues in the pomeron exchange.

2 data tables
Table 1

No description provided.

Table 2

No description provided.