Gregory, P.
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Polarization in Inclusive $\Lambda$ and $\bar{\Lambda}$ Production at Large $p_T$

Lundberg, B. ; Handler, R. ; Pondrom, L. ; et al.
Phys.Rev.D 40 (1989) 3557-3567, 1989.
Inspire Record 287809 DOI 10.17182/hepdata.23077

A study of the inclusive polarization of Λ hyperons produced by 400-GeV/c protons incident on nuclear targets has been performed at Fermilab. The polarization P of the Λ has been mapped over a large range of xF and pT to good precision for pT up to 3.8 GeV/c. The magnitude of the polarization at fixed xF rises with pT to a plateau at about 1 GeV/c, and the size of the plateau increases monotonically with xF. The Λ¯ were found to be unpolarized for pT<2.4 GeV/c. A target-nucleus dependence for the Λ polarization has been observed.

17 data tables
Table 1

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Table 3

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Multiparticle Production by 200-GeV/c Hadrons on Gold, Silver, and Magnesium Targets

Brick, D.H. ; Widgoff, M. ; Beilliere, P. ; et al.
Phys.Rev.D 39 (1989) 2484-2493, 1989.
Inspire Record 282254 DOI 10.17182/hepdata.23227

We have used the Fermilab 30-in. bubble-chamber hybrid spectrometer to study multiparticle production in the interactions of 200-GeV/c protons and π+ and K+ mesons with nuclei of gold, silver, and magnesium. We find that the multiplicities of produced particles and negative particles increase linearly with the number of projectile collisions, with no beam or target dependence. The number of secondary collisions in the nucleus increases significantly less rapidly with the number of projectile collisions than has been reported by a streamer chamber experiment. The properties of secondary collisions suggest that they arise from rescattering of recoil nucleons rather than intranuclear cascade of produced particles. Dispersions of multiplicity distributions at fixed impact parameter are in better agreement with a model of independent sources than with Koba-Nielsen-Olesen scaling.

3 data tables
Table 1

No description provided.

Table 2

PION means all charged secondaries except identified protons.

Table 3

No description provided.


Experimental Evidence for the Nonabelian Nature of {QCD}

The AMY collaboration Park, I.H. ; Schnetzer, S. ; Green, J. ; et al.
Phys.Rev.Lett. 62 (1989) 1713, 1989.
Inspire Record 276619 DOI 10.17182/hepdata.20045

We present evidence for the non-Abelian nature of QCD from a study of multijet events produced in e+e− annihilations from √s =50 to 57 GeV in the AMY detector at the KEK storage ring TRISTAN. A comparison of the three-jet event fraction at TRISTAN to the fraction of the DESY storage ring PETRA shows that the QCD coupling strength αs decreases with increasing Q2. In addition, measurements of the angular distributions of four-jet events show evidence for the triple-gluon vertex.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Analyzing Powers in $\pi^\pm P$ (Polarized) Elastic Scattering From $T (\pi$) = 98-{MeV} to 263-{MeV}

Sevior, M.E. ; Feltham, A. ; Weber, P. ; et al.
Phys.Rev.C 40 (1989) 2780-2788, 1989.
Inspire Record 288842 DOI 10.17182/hepdata.26219

Angular distributions of the analyzing powers for π+p→ and π−p→ elastic scattering have been measured in a single-scattering experiment employing a polarized proton target. Measurements were obtained for pion energies of 98, 139, 166, 215, and 263 MeV. The addition of these data to the existing πp database significantly reduces the uncertainties in all S and P phase shifts for πp reactions over the delta resonance.

10 data tables
Table 1

Measured values of the analyzing power for PI+ P elastic scattering at incident kinetic energy 98 MeV.

Table 2

Measured values of the analyzing power for PI+ P elastic scattering at incident kinetic energy 139 MeV.

Table 3

Measured values of the analyzing power for PI+ P elastic scattering at incident kinetic energy 166 MeV.

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Neutron Induced Pion Production on Carbon, Copper and Bismuth at Intermediate-energies

Buchle, R. ; Franz, J. ; Koncz, P. ; et al.
Nucl.Phys.A 515 (1990) 541-570, 1990.
Inspire Record 287791 DOI 10.17182/hepdata.36854

Inclusive production cross sections of charged pions on carbon, copper and bismuth by neutrons in the energy range of 300–580 MeV have been measured from 54° to 164°. The invariant cross sections can be expressed by Full-size image (<1 K) for the high-energy part of the pion spectra. The slope parameter exhibits a systematic variation with neutron energy and emission angle for the three targets. The dependence of the pion production on the target mass number varies strongly with pion energy and emission angle. The production cross sections are compared with the model of quasi-two-body scaling, the moving-source model and with intranuclear cascade calculations.

1 data table
Table 1

No description provided.


RESONANCE PATTERN OF LOW MASS MUON PAIRS PRODUCED IN 38-GEV/C PI- C INTERACTIONS.

The RISK collaboration Bannikov, A.V. ; Bohm, J. ; Choe, Song Hek ; et al.
DUBNA JINR - 89-486 (89,REC.OCT.) 14p, 1989.
Inspire Record 286947 DOI 10.17182/hepdata.39438

None

3 data tables
Table 1

No description provided.

Table 2

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Table 3

No description provided.


Measurement of the Polarization of the Proton Proton Elastic Reaction at Small Scattering Angles Between 940-{MeV} and 2440-{MeV}

Dalla Torre-Colautti, S. ; Birsa, R. ; Bradamante, F. ; et al.
Nucl.Phys.A 505 (1989) 561-582, 1989.
Inspire Record 288841 DOI 10.17182/hepdata.36886

We have measured the asymmetry of elastic pp scattering at small scattering angles (30–100 mrad) in the Coulomb-nuclear interference region, using the polarized proton beam of Saturne II, a segmented scintillator active target, and two telescopes of multiwire proportional chambers. Results are given at four energies — 940, 1000, 1320 and 2440 MeV-and are compared with phase-shift calculations.

4 data tables
Table 1

No description provided.

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Neutron Induced Production of Protons, Deuterons and Tritons on Copper and Bismuth

Franz, J. ; Koncz, P. ; Rossle, E. ; et al.
Nucl.Phys.A 510 (1990) 774-802, 1990.
Inspire Record 285052 DOI 10.17182/hepdata.36874

Inclusive cross sections for production of protons, deuterons and tritons by neutrons in the energy range of 300–580 MeV on copper and bismuth have been measured at five angles between 54° and 164°. The systematic dependence of the invariant cross sections on incident energy and emission angle are evaluated. For the study of the mass-number dependence earlier data on carbon are included. The results are discussed on the basis of different models, like quasi-two-body sealing or moving-source model.

8 data tables
Table 1

THE ERRORS VARY BETWEEN 2 AND 9 PCT.

Table 2

THE ERRORS VARY BETWEEN 2 AND 9 PCT.

Table 3

THE ERRORS VARY BETWEEN 2 AND 9 PCT.

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Measurements of the $u$ Valence Quark Distribution Function in the Proton and $u$ Quark Fragmentation Functions

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.
Nucl.Phys.B 321 (1989) 541-560, 1989.
Inspire Record 276746 DOI 10.17182/hepdata.33218

A new determination of the u valence quark distribution function in the proton is obtained from the analysis of identified charged pions, kaons, protons and antiprotons produced in muon-proton and muon-deuteron scattering. The comparison with results obtained in inclusive deep inelastic lepton-nucleon scattering provides a further test of the quark-parton model. The u quark fragmentation functions into positive and negative pions, kaons, protons and antiprotons are also measured.

6 data tables
Table 1

No description provided.

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Measurement of the Parameters $N$(0skn), $D$(0n0n) and $K$(0sk0) in $P P$ Elastic Scattering Between 0.84-{GeV} and 2.1-{GeV}

Lac, C.D. ; Ball, J. ; Bystricky, J. ; et al.
Nucl.Phys.B 321 (1989) 269-283, 1989.
Inspire Record 284690 DOI 10.17182/hepdata.33254

The spin-dependent observables N 0 s ″ kn , D 0 n 0 n and K 0 s ″ k 0 in pp elastic scattering were measured at nine energies between 0.84 and 2.1 GeV using the SATURNE II polarized proton beam and the Saclay frozen spin polarized target. The beam polarization was oriented longitudinally and the target polarization was oriented vertically. Precession of the recoil particle spin in the target holding field introduces a small contribution from other parameters. The present results for K 0 s ″ k 0 and D 0 n 0 n agree with our previous measurements of the same observables carried out in different beam and target spin configurations as well as with previously existing measurements. The observable N 0 s ″ kn had not been measured previously above 0.58 GeV. 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.

9 data tables
Table 1

No description provided.

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Table 3

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