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.
A polarized proton beam extracted from SATURNE II, the Saclay polarized target with$^6$Li compounds, and
The polarization transfer parameter KNN measured with polarized protons on the polarized LiH and LiD targets. The relative uncertainty due to the P-C analysing power is +- 6 PCT.
A polarized proton beam extracted from SATURNE II and the Saclay polarized proton target were used to measure the rescattering observables$K_{onno}$and
No description provided.
Spin transfer from circularly polarized real photons to recoiling hyperons has been measured for the reactions $\vec\gamma + p \to K^+ + \vec\Lambda$ and $\vec\gamma + p \to K^+ + \vec\Sigma^0$. The data were obtained using the CLAS detector at Jefferson Lab for center-of-mass energies $W$ between 1.6 and 2.53 GeV, and for $-0.85<\cos\theta_{K^+}^{c.m.}< +0.95$. For the $\Lambda$, the polarization transfer coefficient along the photon momentum axis, $C_z$, was found to be near unity for a wide range of energy and kaon production angles. The associated transverse polarization coefficient, $C_x$, is smaller than $C_z$ by a roughly constant difference of unity. Most significantly, the {\it total} $\Lambda$ polarization vector, including the induced polarization $P$, has magnitude consistent with unity at all measured energies and production angles when the beam is fully polarized. For the $\Sigma^0$ this simple phenomenology does not hold. All existing hadrodynamic models are in poor agreement with these results.
Coefficients Cx and Cz for the reaction GAMMA P --> K+ SIGMA0 for incident energy = 1.534 GeV and W = 1.939 GeV.
The spin dependent observables N 0s n ″ k , K 0s″s0 and D 0s″0k in pp elastic scattering were measured at 11 energies between 0.84 and 2.7 GeV using the SATURNE II polarized proton beam and the Saclay frozen spin polarized target. The beam polarization was oriented in the vertical plane, the target polarization was oriented along the incident beam direction. Below 1 GeV the present data agree with previously existing measurements. Below 1.3 GeV they are compared with the predictions of the Saclay-Geneva phase shift analysis. The results will improve the phase shift analysis solutions and will contribute to their extensions towards higher energies. Together with our previous results the data allow a direct reconstruction of the pp elastic matrix over the energy region from 0.84 too 2.7 GeV.
No description provided.
The spin-dependent observables N 0 nkk , D 0 s ″0 k and K 0 s ″ k 0 in pp elastic scattering were measured at 11 energies between 0.84 and 2.7 GeV using the SATURNE II polarized proton beam and the Saclay frozen-spin polarized target. The beam and target polarizations were oriented longitudinally. Precession of the recoil-particle spin in the target holding field introduces small contributions from other parameters. The present data agree with the few previously existing measurements. Below 1.3 GeV our data are compared with the predictions of the Saclay-Geneva phase-shift analysis. The new results will considerably affect the phase-shift analysis solutions and will contribute to their extension towards higher energies.
Data is given as a combination of the N(ONLL) and KLL parameters. The relative factor BETA is given for each data point.
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