Gordon, H.A.
Pion-Proton Scattering
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The Reactions $pp \to pp$ $\pi^+ \pi^-, K^+ p \to K^+ p$ $\pi^+ \pi^-$, $\pi^+ p \to \pi^+ p$ $\pi^+ \pi^-$ and $\pi^- p \to \pi^+ \pi^-$ at 147 GeV/c

Brick, D.H. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Z.Phys.C 19 (1983) 1-9, 1983.
Inspire Record 194363 DOI 10.17182/hepdata.16321

We have studied the reactionspp→ppπ+π-,K+p→K+pπ+π−π, π+p→ π+,pπ+π− and π−p →π+π− at 147 GeV/c using the 30-inch Fermilab hybrid system. All four reactions were detected with the same apparatus and analyzed in the same way. The energy dependence of the channel cross section was found to beAp−0.6+B for thepp reaction andAp−1+B for the other three. About 90% of the cross section at 147 GeV/c can be accounted for by either beam or target diffraction. Some of the remaining cross section may come from double Pomeron exchange reactions which we tried to isolate. We have tested the hypothesis of a factorizable Pomeron and our data indicates a violation of this hypothesis. We show that the 3π mass enhancement in the mass region 1.2–1.4 GeV is diffractively produced in the π± beam reactions. Fourprong, four-constraint and six-prong, four-constraint cross sections are reported.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

CROSS SECTIONS FOR DIFFRACTION DISSOCIATION OF BEAM. FEYNMAN X OF OUTGOING PROTON <-0.96.

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Topological, Total and Elastic Cross-sections for $K^+ p$, $\pi^+ p$ and $p p$ Interactions at 147-{GeV}/$c$

Brick, D. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Phys.Rev.D 25 (1982) 2794, 1982.
Inspire Record 11840 DOI 10.17182/hepdata.4111

The Fermilab hybrid 30-in. bubble-chamber spectrometer was exposed to a tagged 147-GeV/c positive beam containing π+, K+, and p. A sample of 3003 K+p, 19410 pp, and 20745 π+p interactions is used to derive σn, 〈n〉, f2cc, and 〈nc〉D for each beam particle. These values are compared to values obtained at other, mostly lower, beam momenta. The overall dependence of 〈n〉 on Ea, the available center-of-mass energy, for these three reactions as well as π−p and pp interactions has been determined.

13 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive Strange Resonance Production in $p p$, $\pi^+ p$ and $K^+ p$ Interactions at 147 GeV/c

Brick, D. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Phys.Rev.D 25 (1982) 2248-2258, 1982.
Inspire Record 176545 DOI 10.17182/hepdata.23976

We have studied the inclusive production of K*±(890) and Y*±(1385) in pp, π+p, and K+p interactions at 147 GeV/c. The experiment used the Fermilab 30-inch hydrogen bubble chamber with the hybrid spectrometer system. Results are based on a sample of 1916 observed KS and 932 observed A. Inclusive cross sections are given for K*± and Y*± production from the three beams, and comparisons are made with experiments at other energies. Feynman-x and transverse-momentum-squared distributions are also calculated. The results suggest that the K*− is entirely produced in the central region, while the K*+ includes a component from beam fragmentation. Comparisons are made with the additive quark model.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Low Mass Electron Pair Anomaly in 17-{GeV}/c $\pi^- P$ Collisions

Stekas, J. ; Abshire, G. ; Adams, M.R. ; et al.
Phys.Rev.Lett. 47 (1981) 1686-1689, 1981.
Inspire Record 172147 DOI 10.17182/hepdata.20624

Inclusive e+e− production in 17-GeV/c π−p collisions has been measured. An excess of e+e− pairs over those from known sources for 0.1<~mee<~0.6 GeV and x<0.5 was found. No evidence is found for enhancements in specific final states involving electrons and photons or charged particles. The photon multiplicity associated with these pairs is measured.

1 data table
Table 1

No description provided.


Inclusive and Semiinclusive $\rho^0$ Production in $\pi^+ / \pi^- / K^+ / P P$ Interactions at 147-{GeV}/$c$

Schouten, M. ; De Bock, H. ; Dziembowski, Z. ; et al.
Z.Phys.C 9 (1981) 93-104, 1981.
Inspire Record 170594 DOI 10.17182/hepdata.1419

In an experiment with the 30-inch Hybrid Spectrometer at Fermilab we have obtained the inclusive and semi-inclusive production cross sections of the ϱ0 meson using a conventional background subtraction technique. Production cross sections for the ϱ0 are derived as a function of the Feynman scaling variablex, and the transverse variablespt2 andEt=(pt2+M2)1/2. The longitudinal distributions are compared with the (1−x) dependence of the proton and meson valence quark structure functions, using various forms of recombination and fragmentation models. The transverse distributions are compared with thermodynamic models. We give density matrix elements for the ϱ0 production from pions in the extreme forward region.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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The Effective Energy Dependence of the Charged Particle's Multiplicity in $P / \pi^+ / K^+$ Interactions on Protons at 147 GeV/c

Brick, D. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Phys.Lett.B 103 (1981) 241-246, 1981.
Inspire Record 170358 DOI 10.17182/hepdata.6707

The energy dependence of the average of the charged multiplicity and its dispersion in π + /K + /p interaction on protons at 147 GeV/ c is found to be the same as in e + e − annihilations if an “effective energy” variable is used instead of the total energy. The effective energy S eff is defined as the invariant mass of all secondaries left after the two leading particles have been removed. Fitting the expression aS eff b to the average charge multiplicity 〈 n ch 〉, we find the power b to be in good agreement with the value of 0.25 predicted by Fermi's statistical model and by Landau's hydrodynamical model.

6 data tables
Table 1

BINS IN WEFF SELECTED SO AS TO YIELD 200 EVENTS IN EACH BIN.

Table 2

200 EVENTS IN EACH BIN IN WEFF.

Table 3

50 EVENTS IN EACH BIN IN WEFF.

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Analysis of the Inclusive Reaction $\pi^- p \to K^*$ (890) X0 at 10-{GeV}/c

The Bari-Bonn-CERN-Daresbury-Glasgow-Liverpool-Milan-Vienna collaboration Di Gennaro, V. ; Evangelista, C. ; Ghidini, B. ; et al.
Nucl.Phys.B 173 (1980) 107-126, 1980.
Inspire Record 153000 DOI 10.17182/hepdata.34495

Experimental results on the reaction π − p → K ∗0 (890) X 0 at 10 GeV /c are presented. By using the K ∗0 polarization measurements, a detailed study of the production has been carried out as a function of the missing mass squared and of the four-momentum trasnfer squared to the K ∗0 . We found that: (a) K ∗0 production is dominated by natural parity exchange; (b) K ∗0 helicity-zero production dominates the unnatural parity exchange contribution and (c) the main features of the reaction are in agreement with the predictions of the finite mass sum rules.

4 data tables
Table 1

TO TAL (NATURAL+UNATURAL PARITY EXCHANGE) CROSS-SECTIONS.

Table 2

NATURAL PARITY EXCHANGE CROSS-SECTIONS.

Table 3

UNATURAL PARITY EXCHANGE CROSS-SECTIONS.

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K*0 (890) POLARIZATION MEASUREMENTS IN THE HYPERCHARGE EXCHANGE REACTION PI- P ---> K*0 (890) LAMBDA0 / SIGMA0 AT 10-GEV/C

The BARI-BONN-CERN-DARESBURY-GLASGOW-LIVERPOOL-MILAN-VIENNA collaboration Evangelista, C. ; Ghidini, B. ; Palano, A. ; et al.
Nucl.Phys.B 165 (1980) 383-394, 1980.
Inspire Record 157497 DOI 10.17182/hepdata.34585

K ∗0 (890) production in the hyperchange exchange reaction π − p → K ∗0 (890) Λ 0 Σ 0 at 10 GeV/ c (28 448 events) is discussed. An amplitude analysis in the t ′ range up to 1 GeV 2 shows that the production mechanism is dominated by natural parity exchange (∼84%). Comparisons are made with predictions from a Regge model and a quark model.

2 data tables
Table 1

DENSITY MATRIX ELEMENTS IN THE GOTTFRIED-JACKSON SYSTEM ALLOWING FOR COHERENT S-WAVE BACKGROUND TO P-WAVE BREIT-WIGNER K*(892)0 RESONANCE.

Table 2

No description provided.


Inclusive Production of Neutral Strange Particles by 147 GeV/c $\pi^+/ K^+/ p$ Interactions in Hydrogen

Brick, D. ; Shapiro, A.M. ; Widgoff, M. ; et al.
Nucl.Phys.B 164 (1980) 1, 1980.
Inspire Record 156268 DOI 10.17182/hepdata.8251

Results are presented from a study of inclusive neutral strange particle production by a 147 GeV/ c tagged π + /K + /p beam in the Fermilab 30-inch hydrogen bubble chamber. The experiment made use of the proportional hybrid spectrometer system. Results are based on 995 K S 0 , 485 Λ, and 83 Λ found in a sample of 132 000 pictures. Cross sections are given for inclusive production of these particles by each of the three beam particles, and comparisons are made with measurements at other energies. Topological cross sections are also calculated, and KNO multiplicity scaling is investigated. Distributions are presented of invariant cross sections as functions of the Feynman scaling variable x and c.m. rapidity y . The transverse momentum-squared distributions with their fitted slopes are also given. Comparisons are made of the production characteristics for the three beam types.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Y* K AND Y* K* PRODUCTION IN pi+ p INTERACTIONS AT 10.3-GeV/c

Goddard, M.C. ; Key, A.W. ; Luste, G.J. ; et al.
Phys.Rev.D 19 (1979) 1350, 1979.
Inspire Record 7416 DOI 10.17182/hepdata.24321

The reactions π+p→Σ+(1385)K+ and π+p→Σ+(1385)K*+(890) are examined. The Σ+(1385)K+ differential cross section for −t′<0.5 GeV2 and spin density matrix elements agree with a Regge-pole model incorporating (nondegenerate) vector and tensor K* exchange with dominant M1 coupling. The Σ+(1385)K*+(890) density matrix elements are consistent with the quark-additivity predictions. A Y*+ at a mass of 1700 MeV is also observed in the Λπ+ mass distribution, produced opposite both K+ and K*+(890).

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

GOTTFRIED-JACKSON FRAME.

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