Ball, R.C.
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Proton Proton Elastic Scattering from 150-MeV to 515-MeV

Bugg, D.V. ; Edgington, J.A. ; Amsler, Claude ; et al.
J.Phys.G 4 (1978) 1025, 1978.
Inspire Record 123232 DOI 10.17182/hepdata.38563

The parameters D, R, R' and P for pp elastic scattering have been measured in the centre-of-mass angular range 13 degrees to 58 degrees with an accuracy of about +or-0.02 at 209, 324, 379, 425 and 515 MeV. These results are incorporated with earlier data into a phase-shift analysis. Phase-shifts are generally in agreement with the theoretical predictions of the Paris group, although the F-wave spin-orbit combination is rather stronger than predicted. The fitted value for the pi 0pp coupling constant in g02=14.06+or-0.65.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of the pi d Elastic Differential Scattering Cross Cross-Section for Momenta from 343-MeV/c to 637-MeV/c

Cole, R.H. ; Mccarthy, J.S. ; Minehart, R.C. ; et al.
Phys.Rev.C 17 (1978) 681-693, 1978.
Inspire Record 134673 DOI 10.17182/hepdata.26365

The differential cross section for scattering of pions on deuterons was measured at LAMPF at laboratory momenta of 343, 441, 539, and 637 MeVc, using an E−ΔE method to identify the recoil deuterons. Angles ranged from 40° to 160° in the center of mass system. The momentum resolution was σ=±3.5% and the angular resolution was ± 1.70° in the laboratory system. The experimental method is discussed, and results are presented and compared with other experimental data as well as with various theoretical calculations. [NUCLEAR REACTIONS H2(π,π); E=230,323,417,512 MeV. D2O, CD2 targets. Measured σ(θ), θ=40∘−160∘, Δθ=1.7∘, Δpp=3.5%.]

4 data tables
Table 1

X ERROR D(THETA) = 1.7000 DEG.

Table 2

X ERROR D(THETA) = 1.7000 DEG.

Table 3

X ERROR D(THETA) = 1.7000 DEG.

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Polarization Measurement of the $\Sigma^+$ Produced in the Line Reversed Reactions $\pi^+ p \to K^+ \Sigma^+$ and $K^- p \to \pi^- \Sigma^+$ at 7-{GeV}/$c$ and 11.6-{GeV}/$c$

Baker, P.A. ; Chima, J.S. ; Dornan, P.J. ; et al.
Phys.Rev.Lett. 40 (1978) 678, 1978.
Inspire Record 129108 DOI 10.17182/hepdata.20914

The polarization of the Σ+ has been measured for the line-reversed reactions π+p→K+Σ+ and K−p→π−Σ+ at 7 and 11.6 GeV/c using the SLAC Hybrid Facility. Since the Σ+ decay is observed in the bubble chamber, the trigger of the flash lamps on a fast K+(π−) did not bias the polarization measurements. We find that the Σ+ polarizations from the two reactions have opposite signs but similar magnitudes and are in much better agreement with the predictions of weak exchange degeneracy than previous lower-energy comparisons.

1 data table
Table 1

No description provided.


Confirmation of Exchange Degeneracy Predictions in the Line Reversed Reactions: $\pi^+ p \to K^+ Y^*(1385)$ and $K^- p \to \pi^- Y^*(1385)$ at 11.6-{GeV}/$c$

Ballam, Joseph ; Bouchez, J. ; Carroll, J.T. ; et al.
Phys.Rev.Lett. 41 (1978) 676, 1978.
Inspire Record 130550 DOI 10.17182/hepdata.20815

We have measured in a single experimental setup the differential cross sections and polarizations of the Y*(1385) produced in the two line-reversed reactions π+p→K+Y*(1385) (260 eV/μb) and K−p→π−Y*(1385) (180 eV/μb) at 11.5 GeV/c. We compare these results to Σ+ production in the same experiment. The data have been derived from a triggered bubble-chamber experiment using the SLAC Hybrid Facility. We find that both helicity-flip-dominated (Y*) and helicity-nonflip-dominated (Σ) processes are consistent with weak-exchange-degeneracy predictions.

5 data tables
Table 1

Axis error includes +- 10/10 contribution.

Table 2

Axis error includes +- 10/10 contribution.

Table 3

Axis error includes +- 10/10 contribution.

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A Search for Six Quark States

Carroll, A.S. ; Chiang, I.-H. ; Johnson, R.A. ; et al.
Phys.Rev.Lett. 41 (1978) 777, 1978.
Inspire Record 131409 DOI 10.17182/hepdata.50368

We have searched the missing-mass spectrum of the reaction pp→K+K+X for a narrow six-quark resonance in the mass range 2.0-2.5 GeV/c2. No narrow structure was observed. Upper limits for the production cross section of such a state depend upon mass and vary from 30 to 130 nb.

1 data table
Table 1

No description provided.


Production of $J/\psi$ in 16-{GeV} and 22-{GeV} $\pi^-$ Cu Collisions

LeBritton, J. ; McCal, D. ; Melissinos, A.C. ; et al.
Phys.Lett.B 81 (1979) 401-404, 1979.
Inspire Record 7053 DOI 10.17182/hepdata.50278

We have measured the inclusive production of J ψ in 16 and 22 GeV π − copper collisions in a wide aperture magnetic spectrometer. The cross section per Cu nucleus for x > 0 corrected for branching ratio is 64 ± 38 nb at 16 GeV and 196 ± 38 nb at 22 GeV. As threshold is approached, the mean values of the Feynman x distribution increase and the cross section for J ψ production drops steeply. This can be understood in terms of the quark-fusion model where the antiquark content of the pion makes an increasingly significant contribution as M 2 s increases.

2 data tables

Study of the Reaction $\pi^- p \to N K^0_S K^0_S$ at 6.0-{GeV}/$c$ and 7.0-{GeV}/$c$

Polychronakos, V.A. ; Cason, N.M. ; Bishop, J.M. ; et al.
Phys.Rev.D 19 (1979) 1317, 1979.
Inspire Record 7273 DOI 10.17182/hepdata.24309

The KS0KS0 system produced in the reaction π−p→nKS0KS0 at 6.0 and 7 0 GeV/c has been studied utilizing the ANL 1.5-m streamer-chamber facility. A 400 000-photograph exposure yielded 5096 unweighted nKS0KS0 events. The cross section for this reaction was determined to be 9.6 ± 1.3 μb at 6.0 GeV/c and 8.7 ± 1.1 μb at 7.0 GeV/c. The decay angular distributions were parametrized in terms of moments of the spherical harmonics. The 〈Y40〉 moment was fitted to interfering Breit-Wigner amplitudes for the f and f′ mesons. Using this fit, the branching ratio R=Γ(f→KK¯)Γ(f→all) was found to be (2.3 ± 0.8)%. An energy-independent production-amplitude analysis revealed an enhancement in the S-wave amplitude near 1300 MeV. The properties of the S-wave enhancement are discussed and compared with those observed in other recent experiments. Extrapolated cross sections for the reaction ππ→KS0KS0 are presented. We find a cross section considerably below the S-wave unitarity limit in the S* region.

1 data table
Table 1

FROM FIT TO D-WAVE (M=0) KS KS, CORRECTED FOR <K+ K-> AND <KL KL> DECAY MODES.


PRODUCTION AND DECAY ANGULAR DISTRIBUTIONS OF THE Y* (1385) IN THE LINE REVERSED REACTIONS: pi+ p ---> K+ Y* (1385) AND K- p ---> pi- Y* (1385) AT 11.5-GeV/c

Cautis, C.V. ; Ballam, Joseph ; Bouchez, J. ; et al.
Nucl.Phys.B 156 (1979) 507-531, 1979.
Inspire Record 133382 DOI 10.17182/hepdata.34679

We have measured in a single experimental setup, the differential cross sections and decay angular distributions of the Y ∗ (1385) produced in the two line-reversed reactions: π + p → K + Y ∗+ (1385) (279 events/ω b ) and K − p → π − Y ∗+ (1385) (190 events/ωb) at 11.5 GeV/ c . The data have been derived from a triggered bubble-chamber experiment using the SLAC Hybrid Facility. We find the differential cross sections and Y ∗ polarizations for the two reactions to be in agreement with exchange-degeneracy predictions, if kinematic differences are taken into account. The Stodolsky-Sakurai and additive quark model predictions are in agreement with the main features of the decay angular distributions of the Y ∗ (1385), except for small violations at low momentum transfer, which can be associated with a finite helicity non-flip contribution in the forward direction.

6 data tables
Table 1

Axis error includes +- 10/10 contribution.

Table 2

THESE FINAL DIFFERENTIAL CROSS SECTIONS ARE INCLUDED IN THE RECORD OF J. BALLAM ET AL., PRL 41, 676 (1978).

Table 3

TRANSVERSITY AMPLITUDES FOR SIG(1385P13)+ PRODUCTION. THE IMAGINARY PARTS OF T(11) AND T(-1-1) WERE ARBITRARILY FIXED AT ZERO.

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$\rho^0$ Production in $\pi^- p$ Interactions at 100, 200 and 360 GeV/c

Higgins, P.D. ; Shephard, W.D. ; Biswas, N.N. ; et al.
Phys.Rev.D 19 (1979) 65, 1979.
Inspire Record 7275 DOI 10.17182/hepdata.4591

Inclusive and semi-inclusive cross sections for gp0 production in 100, 200, and 360 GeV/c π−p interactions are presented. Differential cross sections for ρ0 production as functions of c.m. rapidity and transverse momentum are compared with the corresponding differential cross sections for pion production. Effects of various methods of estimating background on the values obtained for ρ0 production cross sections are discussed. About 10% of the final-state charged pions appear to come from ρ0 decay. Thus, while ρ0 production and decay is a significant source of final-state pions, other sources must contribute the majority of the produced pions.

14 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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The Contribution of $q \bar{q}$ Annihilations to Dimuon Production in $\pi N$ Interactions

Reece, C. ; LeBritton, J. ; McCal, D. ; et al.
Phys.Lett.B 85 (1979) 427-431, 1979.
Inspire Record 7886 DOI 10.17182/hepdata.27323

We present data on dimuon production by 16 GeV π + and π − beams on a Cu target. From the data we evaluate, for π − N collisions, the fraction of dimuon events that originate from the annihilation process q q ̄ → μ + μ − . Using this information the experimentally determined cross section for the process q q ̄ → μ + μ − is observed to be in agreement with the Drell-Yan model over a wide range of incident energies. The observed deviations from exact scaling are of the order predicted by QCD calculations for the Q 2 -dependence of the nucleon and the pion structure function.

2 data tables
Table 1

CROSS SECTIONS ARE PER COPPER NUCLEUS.

Table 2

CROSS SECTIONS ARE PER COPPER NUCLEUS.