An investigation of the spin structure of the proton in deep inelastic scattering of polarized muons on polarized protons.

The European Muon collaboration Ashman, J. ; Badelek, B. ; Baum, Guenter ; et al.
Nucl.Phys.B 328 (1989) 1, 1989.
Inspire Record 280143 DOI 10.17182/hepdata.49587

The spin asymmetry in deep inelastic scattering of longitudinally polarised muons by longitudinally polarised protons has been measured in the range 0.01<×<0.7. The spin dependent structure function g 1 ( x ) for the proton has been determined and, combining the data with earlier SLAC measurements, its integral over x found to be 0.126±0.010(stat.)±0.015(syst.), in disagreement with the Ellis-Jaffe sum rule. Assuming the validity of the Biorken sum rule, this result implies a significant negative value for the integral of g 1 for the neutron. These integrals lead to the conclusion, in the naïve quark parton model, that the total quark spin constitutes a rather small fraction of the spin of the nucleon. Results are also presented on the asymmetries in inclusive hadron production which are consistent with the above picture.

7 data tables

THE MEAN Q**2 FOR EACH OF THE 10 VALUES OF X BELOW ARE 3.5,4.5,6.0, 8.010.3,12.9,15.2,18.0,22.5,29.5.

No description provided.

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Measurement of a Mixed Spin Spin Correlation Parameter for $n p$ Elastic Scattering

Garnett, R. ; Rawool, M. ; Carlson, V. ; et al.
Phys.Rev.D 40 (1989) 1708, 1989.
Inspire Record 25430 DOI 10.17182/hepdata.23054

The mixed spin-spin correlation parameter Cσσ≈0.5CSS−0.8CSL for np elastic scattering was measured for incident-neutron-beam kinetic energies of 484, 634, and 788 MeV over the center-of-mass angular range 75°-180°. These Cσσ data are important for determining the I=0 nucleon-nucleon amplitudes and provide strong constraints on the phase-shift solutions. It was found that the P11, S13, and D13 isospin-0 partial waves are most strongly affected.

3 data tables

Mixed spin parameter POL.POL(NAME=CXX) is given by 0.475 * CSS + 0.088 CNN + 0.1390 CLL - 0.744 CSL.

Mixed spin parameter POL.POL(NAME=CXX) is given by 0.506 * CSS + 0.064 CNN + 0.163 CLL - 0.809 CSL.

Mixed spin parameter POL.POL(NAME=CXX) is given by 0.528 * CSS + 0.050 CNN + 0.178 CLL - 0.824 CSL.


Spin Correlation Parameter A(nn) ($\theta^*$) for $n p$ Elastic Scattering at 790-{MeV}

Nath, S. ; Glass, G. ; Hiebert, J.C. ; et al.
Phys.Rev.D 39 (1989) 3520, 1989.
Inspire Record 25429 DOI 10.17182/hepdata.23226

The spin-correlation parameter Ann for free n-p elastic scattering has been measured for the first time for incident-neutron-beam energy En=790 MeV and c.m. angles 48°≤θ*≤149°. The data are compared with the widely differing predictions of several phase-shift analyses, clearly favoring one of them. They also are compared with recently published quasifree Ann data for the more limited c.m. angular region 98°≲θ*≲122°.

1 data table

No description provided.


ELASTIC P (POLARIZED) P (POLARIZED) SCATTERING BETWEEN 240-MEV AND 470-MEV

Onel, Y. ; Hausammann, R. ; Heer, E. ; et al.
Phys.Rev.D 40 (1989) 35-43, 1989.
Inspire Record 285140 DOI 10.17182/hepdata.23076

The polarization parameter Pn000, the two-spin parameters Dn0n0, Kn00n, Ds′0s0, Ds′0k0 and the three-spin parameters Ms′0sn and Ms′0kn have been measured for pp elastic scattering angles between 60° and 88° center of mass at 241 and 314 MeV incident kinetic energies, and between 38° c.m. and 98° c.m. at 341, 366, and 398 MeV. At 473 MeV, only Pn000 and Ds′0k0 were measured between 34° c.m. and 62° c.m. The experiment was performed at SIN using a polarized proton beam and a polarized butanol target. The polarization of the scattered proton was analyzed in a carbon polarimeter. The influence of these high-precision data on the Saclay-Geneva phase-shift analysis is discussed.

6 data tables

Statistical errors only.

Statistical errors only.

Statistical errors only.

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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

No description provided.

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

No description provided.


Measurement of Analyzing Power and Spin Correlations in $N P$ Elastic Scattering at 0.744-{GeV} and 0.794-{GeV} Using a Deuteron Polarized Beam

De Lesquen, A. ; Lehar, F. ; Van Rossum, L. ; et al.
Nucl.Phys.B 304 (1988) 673-686, 1988.
Inspire Record 268253 DOI 10.17182/hepdata.33258

The np and the pp analyzing powers A oono d and spin correlations A oonn d and A oosk d were measured simultaneously using the SATURNE II polarized deuteron beam at 0.744 and 0.794 GeV/nucleon. The results for the pp observables coincide with the free pp elastic scattering data. We thus can assume that also the np analyzing power A oono d and spin correlations A oonn d and A oosk d are equal to those for scattering of free polarized neutrons. The np data cover the angular region 95°⩽ θ CM ⩽122°. Our results for A oono d (np) confirm the phase-shift analysis predictions but spin correlations A oonn d (np) and A oosk d (np) have never been measured in this energy region and will considerably affect the PSA solution. Present results allow conclusions about the angular dependence near the minimum of A oono (np) and A oonn (np) in the vicinity of 0.8 GeV.

12 data tables

No description provided.

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Measurement of the Spin Correlation A(ookk) in $N P$ Elastic Scattering Between 0.63-{GeV} and 1.08-{GeV}

Ball, J. ; Lac, C.D. ; Lehar, F. ; et al.
Z.Phys.C 40 (1988) 193-197, 1988.
Inspire Record 269772 DOI 10.17182/hepdata.15598

We present the measurements of the spin correlation parameterAookk(np). A longitudinally polarized beam of free neutrons obtained from the break-up of polarized deuterons was scattered on the longitudinally polarized Saclay frozen-spin proton target. Measurements were carried out at SATURNE II, at neutron beam kinetic energies of 0.63, 0.88, 0.98 and 1.08 GeV. The data points cover the angular region from about 40° to 110° CM. The observed angular dependence ofAookk(np) at 0.63 GeV agree with the phase shift analysis predictions except at small angles.

4 data tables

First set of data is with neutron counter hodoscope. Second is using a charge-exchange in the carbon block.

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Measurement of C(ll) and C(sl) in $N P$ Elastic Scattering at 484-{MeV} and 634-{MeV}

Burleson, G.R. ; Faucett, J.A. ; Fontenla, C.A. ; et al.
Phys.Rev.Lett. 59 (1987) 1645, 1987.
Inspire Record 21907 DOI 10.17182/hepdata.3247

The spin-spin correlation parameters CLL=(L,L;0,0)=ALL and CSL=(S,L;0,0)=ASL for np elastic scattering were measured for incident polarized-neutron–beam kinetic energies of 484 and 634 MeV over the center-of-mass angles from ≃80° to 180°. The data are important for determining the I=0 nucleon-nucleon amplitudes. These results are compared with phase-shift calculations.

5 data tables

No description provided.

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Measurement of the Spin Dependent Neutron Proton Total Cross-section Differences $\Delta \Sigma^- T$ and $\Delta \Sigma^-$l Between 0.63-{GeV} and 1.08-{GeV}

Lehar, F. ; De Lesquen, A. ; Van Rossum, L. ; et al.
Phys.Lett.B 189 (1987) 241-244, 1987.
Inspire Record 249897 DOI 10.17182/hepdata.30198

We present first measurements of total cross section differences Δσ T and Δσ L for a polarized neutron beam transmitted through a polarized proton target. Measurements were carried out at SATURNE II, at 0.63, 0.88, 0.98 and 1.08 GeV. The results are compared with Δσ L data points deduced from p-d and p-p transmission experiments, and with phase shift analyses predictions. The present results together with the corresponding pp data yield two of the three spin dependent forward scattering amplitudes for isospin I =0.

1 data table

Statistical errors are statistics and random fluctuations. Systematic error contains uncertainties in beam and target polarizations, hydrogen content of the target, and residual error due to misalignment.


Observation of a New Structure in the Difference Between the $p p$ Total Cross-sections for Antiparallel and Parallel Longitudinal Spin States

Auer, I.P. ; Colton, E. ; Halpern, H. ; et al.
Phys.Rev.D 34 (1986) 2581, 1986.
Inspire Record 230143 DOI 10.17182/hepdata.23425

We have measured the difference between the pp total cross sections for parallel and antiparallel longitudinal spin states at beam momenta of 2.75, 2.92, 3.25, and 3.48 GeV/c. These results reveal possible new structure in this momentum range.

1 data table

Data read from graph. Statistical errors only.