Aboona, B.E.
Polarization
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Analyzing Power Measurement in Inclusive $\pi^0$ Production at High $\chi_F$

Bonner, B.E. ; Buchanan, J.A. ; Carey, D.C. ; et al.
Phys.Rev.Lett. 61 (1988) 1918, 1988.
Inspire Record 269386 DOI 10.17182/hepdata.2928

The analyzing power AN in inclusive π0 production has been measured with use of the new 185-GeV/c Fermilab polarized proton beam. We obtain the value AN=0.10±0.03 for π0's in the kinematic region 0.2<xF<0.8 and 0.3<pT<1.2 GeV/c. In certain models of particle production this suggests that the spin of the proton is carried by its valence quarks.

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Individual polarisation measurements.

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Spin Parameter Measurements in $\Lambda$ and $K_S$ Production

Bonner, B.E. ; Buchanan, J.A. ; Clement, J.M. ; et al.
Phys.Rev.D 38 (1988) 729-741, 1988.
Inspire Record 268865 DOI 10.17182/hepdata.23270

The Brookhaven Alternating Gradient Synchrotron polarized proton beam incident on a beryllium target was used for inclusive Λ production at beam momenta of 13.3 and 18.5 GeV/c. The beam polarization was transverse to the beam direction with magnitude 0.63 at 13.3 GeV/c and 0.40 at 18.5 GeV/c. The Λ polarization was measured and found to be in agreement with results from earlier experiments which used unpolarized proton beams. Analyzing power AN and spin transfer DNN of the Λ’s were both measured and compared with a hyperon-polarization model in which the polarization arises from a Thomas-precession effect. There is good agreement with its predictions: AN=0 and DNN=0. In particular, our measurement of 〈DNN〉=-0.009±0.015 supports the idea that the valence quarks carry all of the hadron spin, since this assumption is implicit in the model’s use of SU(6) wave functions to form final-state hadrons from beam fragments and sea quarks. The presence of substantial KS samples at both beam momenta and Λ¯’s at 18.5 GeV/c prompted a measurement of their analyzing powers, which yielded AN(KS)=-0.094±0.012 at 13.3 GeV/c beam momentum and -0.076±0.015 at 18.5 GeV/c, and AN(Λ¯)=0.03±0.10.

15 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Determination of Proton Nucleon Analyzing Powers and Spin Rotation Depolarization Parameters at 500-{MeV}

Marshall, J.A. ; Barlett, M.L. ; Fergerson, R.W. ; et al.
Phys.Rev.C 34 (1986) 1433-1438, 1986.
Inspire Record 240068 DOI 10.17182/hepdata.26283

500 MeV p→+p elastic and quasielastic, and p→+n quasielastic, analyzing powers (Ay) and spin-rotation-depolarization parameters (DSS, DSL, DLS, DLL, DNN) were determined for center-of-momentum angular ranges 6.8°–55.4° (elastic) and 22.4°–55.4° (quasielastic); liquid hydrogen and deuterium targets were used. The p→+p elastic and quasielastic results are in good agreement; both the p→+p and p→+n parameters are well described by current phase shift solutions.

6 data tables
Table 1

The elastic P P analysing power at 500 MeV incident proton energy. There is an additional overall normalization uncertainty of 1 PCT.

Table 2

The spin depolarization and spin rotation parameters in 500 MeV P P elastic interactions. Additional normalization uncertainty of 1 PCT (2 PCT for DLL and DLS).

Table 3

The elastic P P analysing power at 500 MeV incident proton energy. There is an additional overall normalization uncertainty of 1 PCT.

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THE ENERGY DEPENDENCE OF THE 90-degrees P P ELASTIC SCATTERING DEPOLARIZATION PARAMETER AND AMPLITUDES BETWEEN 0.9-GEV/C AND 1.5-GEV/C

Hollas, C.L. ; Cremans, D.J. ; Ransome, R.D. ; et al.
Phys.Lett.B 143 (1984) 343-346, 1984.
Inspire Record 208375 DOI 10.17182/hepdata.30531

The depolarization parameter D NN for pp elastic scattering at θ cm = 90 ° has been measured at twelve momenta between 0.9 and 1.5 GeV/ c . The moduli of the three transversity amplitudes T 1 , T 3 , and T 4 have been extracted from these data and from previous measurements of the differential cross section and spin correlation parameter A NN (90 °). Smooth energy dependence is found for all three amplitude moduli.

1 data table
Table 1

Axis error includes +- 3/3 contribution (DUE TO UNCERTAINTIES IN THE TARGET ANALYSING POWER).


SPIN DEPENDENCE IN NEUTRON PROTON CHARGE EXCHANGE AT 790-MEV

Ransome, R.D. ; Hollas, C.L. ; Riley, P.J. ; et al.
Phys.Rev.Lett. 48 (1982) 781-784, 1982.
Inspire Record 180615 DOI 10.17182/hepdata.20595

The analyzing power A and spin-transfer parameters KNN, KSS, KSL, and KLL have been measured in the np charge-exchange (np→pn) region at 790 MeV. These data provide new and unique information on the spin dependence of the np interaction in the charge-exchange region. Models which explain the charge-exchange peak in the np elastic differential cross section as being due to interference between one-pion exchange and a slowly varying background are in basic agreement with the data.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

USING PHASE-SHIFT VALUES FOR KLS AND KSL.


Measurement of Neutron-Deuteron Polarization at 35 MeV

Zamudio-Cristi, J. ; Bonner, B.E. ; Brady, F.P. ; et al.
Phys.Rev.Lett. 31 (1973) 1009-1012, 1973.
Inspire Record 945160 DOI 10.17182/hepdata.21394

The neutron polarization asymmetry in neutron-deuteron scattering has been measured from 44.5° to 160° (c.m.) neutron angle. The results display quantitatively the same structure as proton-deuteron polarization data, but discrepancies appear for angles corresponding to those near the minimum of the differential cross section. In this region the polarization is considerably more negative than in the proton-deuteron case, and both are more negative than current theoretical predictions.

2 data tables
Table 1

No description provided.

Table 2

No description provided.