Engler, A.
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A Study of the $\Delta \pi \pi$ System in the Reaction $\pi^- p \to \pi^- p \pi^+ \pi^- \pi^0$ at 4.5-{GeV}/$c$

Sugahara, R. ; Suzuki, A. ; Fukawa, M. ; et al.
Nuovo Cim.A 52 (1979) 373, 1979.
Inspire Record 142331 DOI 10.17182/hepdata.37520

Two (Δ(1238)ππ) enhancements at 1.93 and 2.12 GeV have been observed in an analysis of the invariant-mass spectra of Δ++(1238)π-π0 and Δ++(1238)π-π- from π-p→π-pπ+π-π0 events in 4.5 GeV/c π-p interactions. An enhancement at 2.2 GeV is also seen with a dominant branching to the Δ(1238)ρ system. The 1.93 and 2.12 enhancements seem to be produced mainly through a ρ-meson exchange process. The 2.2 GeV enhancement seems to be produced diffractively and is considered to correspond to theG17(2190) state.

2 data tables
Table 1

No description provided.

Table 2

EXPONENTIAL FITS TO T-DISTRIBUTIONS.


Spin Spin Forces in 6-{GeV}/$c$ Neutron - Proton Elastic Scattering

Crabb, D.G. ; Hansen, P.H. ; Krisch, A.D. ; et al.
Phys.Rev.Lett. 43 (1979) 983, 1979.
Inspire Record 141922 DOI 10.17182/hepdata.20753

Measurement was made of dσdt for n↑+p↑→n+p at P⊥2=0.8 and 1.0 (GeV/c)2 at 6 GeV/c. The 6-GeV/c 53%-polarized neutrons from the 12-GeV/c polarized deuteron beam at the Argonne zero-gradient synchroton were scattered from our 75%-polarized proton target. Both spins were oriented perpendicular to the scattering plane. We found large unexpected spin-spin effects in n−p elastic scattering which are quite different from the p−p spin-spin effects.

1 data table
Table 1

No description provided.


rivet Analysis
Study of the Reaction $e^+ e^- \to p \bar{p}$ in the Total Energy Range 1925-{MeV} - 2180-{MeV}

Delcourt, B. ; Derado, I. ; Bertrand, J.L. ; et al.
Phys.Lett.B 86 (1979) 395-398, 1979.
Inspire Record 141565 DOI 10.17182/hepdata.27308

The e + e − → p p cross section has been measured between 1925 and 2180 MeV. About 50 p p events were detected. The total cross section decreases from 1.31 ± 0.4 nb near 1937 MeV to 0.55 ± 0.2 nb near 2135 MeV. The proton form factors | G E | 2 and | G M | 2 , assumed identical, decrease from 0.15 ± 0.05 to 0.043 ± 0.015. They are an order of magnitude higher than predicted by the well-known dipole fit. The energy range has been scanned in steps of about 2 MeV. No significant structure was found in this p p sample.

1 data table
Table 1

TOTAL CROSS SECTION ASSUMING ISOTROPIC PRODUCTION. RADIATIVE CORRECTIONS CALCULATED USING PEAKING APPROXIMATION (ABOUT 20 PCT). AUTHORS ALSO QUOTE RESULTS FOR LIMITED (COSMIC RAY FREE) ACCEPTANCE AS A CHECK. FORM FACTOR DERIVED ASSUMING ELECTRIC AND MAGNETIC FORM FACTORS EQUAL IN MAGNITUDE.


Measurements of the Double Polarization Parameters $G$ and $H$ in Neutral Pion Photoproduction

Bussey, P.J. ; Rutherglen, J.G. ; Booth, P.S.L. ; et al.
Nucl.Phys.B 159 (1979) 383-396, 1979.
Inspire Record 141663 DOI 10.17182/hepdata.34624

Measurements have been made of the double polarisation parameters G and H in the photoproduction of neutral pions from protons, for incident photon energies between 1300 MeV and 2300 MeV and for pion c.m. angles between 50δ and 80δ. The results are compared with predictions from a recent comprehensive analysis of earlier photoproduction data.

11 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive Production of $D$ and $K$ Mesons in $e^+ e^-$ Annihilation

Piccolo, M. ; Peruzzi, I. ; Rapidis, P.A. ; et al.
Phys.Lett.B 86 (1979) 220-224, 1979.
Inspire Record 141018 DOI 10.17182/hepdata.27301

We present measurements of the cross section for inclusive D and K meson production in e + e − annihilation in the center of mass energy range 3.6 to 5.8 GeV. D production accounts for most of the increase in the total cross section for hadron production in e + e − annihilation at energies above 4 GeV.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Inclusive Strange Particle Production in $\pi^- p$ Reaction at 6-{GeV}/$c$

Sugahara, R. ; Ochiai, F. ; Fukui, Y. ; et al.
Nucl.Phys.B 156 (1979) 237-251, 1979.
Inspire Record 141670 DOI 10.17182/hepdata.8293

The inclusive production of Λ , K S 0 , Σ ± (1385) and K ∗± (892) in π − p interactions at 6 GeV/ c has been studied. The observed cross sections are: σ ( Λ )=0.94±0.06 mb, σ (K S 0 )=0.98±0.06 mb, σ ( Σ + (1385))=60±7 μb , σ ( Σ − (1385))=90±9 μ b, σ( K ∗+ (892))=216±28 μ b and σ( K ∗− (892))=41±8 μ b , respectively. The inclusive spectra of these particles are presented as functions of squared transverse momentum and Feynman scaling variable x . The polarization of Λ has also been investigated. It is found from a comparison with higher-energy data that the inclusive cross sections for Σ ± (1385) and the production ratios Σ ± (1385)/ Λ in π − p at 6 GeV/ c have not reached the high-energy limiting values.

14 data tables
Table 1

No description provided.

Table 2

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Table 3

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A MEASUREMENT OF THE K0(L) p ELASTIC CROSS-SECTION FOR 3 less than or equal to p less than or equal to 13-GeV/c AND .1 less than or equal to |t| less than or equal to 1.3-GeV**2

Cittolin, S. ; Gasparini, F. ; Limentani, S. ; et al.
Nucl.Phys.B 157 (1979) 197-211, 1979.
Inspire Record 7663 DOI 10.17182/hepdata.34662

The cross section for the K L 0 p elastic scattering has been measured for the first time. The incident momentum and momentum transfer ranges are 3 ⩽ p ⩽ 13 GeV/ c , 0.1 ⩽ | t | ⩽ 1.3 GeV 2 . The results are compared to those of other experiments related to ours by isotopic spin conservation, finding agreement with some and discrepancies with others. The differential cross sections have been parametrized in the form A e bt . The coefficients show little or no dependence on energy, with A ≅ 9.8 mb · GeV −2 and b ≅ 4.7 GeV −2 . The effective linear trajectory has been determined and gives α 0 = 0.95 ± 0.15, α ′ = −0.35 ± 0.48 GeV −2 , in good agreement with dominance by pomeron exchange.

3 data tables
Table 1

CROSS SECTIONS DEDUCED FROM THE 46 PCT OF EVENTS WHICH YIELD UNIQUE SOLUTIONS.

Table 2

<RAW> CROSS SECTIONS DEDUCED FROM A STATISTICAL TREATMENT OF ALL EVENTS.

Table 3

<SMOOTHED> CROSS SECTIONS DEDUCED FROM A STATISTICAL TREATMENT OF ALL EVENTS.


rivet Analysis
Cross-Sections and Event Topologies in e+ e- Annihilation at 13-GeV and 17-GeV Observed with the PLUTO Detector

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 81 (1979) 410-415, 1979.
Inspire Record 140294 DOI 10.17182/hepdata.45239

First results from the magnetic detector PLUTO at the new e + e − storage ring PETRA are shown. The ratio R of the cross section for hadron production to that for μ-pair production has been measured to be R = 5.0 ± 0.5 at 13 GeV and 4.3 ±0.5 at 17 GeV. Both values have an additional systematic error of 20%. The events show a typical 2-jet structure. The mean transverse momentum approaches a constant value with increasing energy implying a shrinkage of the jet opening angle.

2 data tables
Table 1

TAU HEAVY LEPTON PAIR CONTRIBUTIONS HAVE BEEN SUBTRACTED. R AT 13 AND 17 GEV, TOGETHER WITH SOME SELECTED LOWER ENERGY MEASUREMENTS FROM PLUTO AT DORIS.

Table 2

Data from earlier preprint DESY-79-06. NUMERICAL VALUES MEASURED OFF GRAPH IN PREPRINT.


MEASUREMENT OF TWO AND THREE SPIN PARAMETERS AT 6-GEV/C USING A TRANSVERSELY POLARIZED BEAM AND TARGET

Beretvas, A. ; Miller, D. ; Auer, I.P. ; et al.
Phys.Rev.D 20 (1979) 21-32, 1979.
Inspire Record 146770 DOI 10.17182/hepdata.24227

Toward the goal of experimentally determining pp elastic scattering amplitudes at 6 GeV/c, we have measured a linear combination of triple-spin correlation parameters and also a linear combination of spintransfer parameters over the |t| range between 0.2 and 1.0 (GeV/c)2. A horizontally polarized beam (S direction) was obtained by precessing the spin of the polarized beam from the Argonne Zero Gradient Synchrotron using a superconducting solenoid. The target protons were polarized vertically (N direction) and the polarization of the recoil protons was measured with a carbon polarimeter. The results are consistent with the amplitude corresponding to π exchange being almost real and positive.

1 data table
Table 1

KSS = (S00S) AND HSNS = (SN0S) MEASURED HERE CONTAIN SMALL ADMIXTURES OF THE OTHER SPIN-TRANSFER AND TRIPLE-SPIN CORRELATION PARAMETERS RESPECTIVELY DUE TO THE POLARIZED TARGET MAGNETIC FIELD - SEE TEXT. MEAN VALUE OF HSNS OVER THIS T-RANGE IS 0.098 +- 0.085. PARITY CONSERVATION REQUIRES THE VANISHING OF THE PARAMETERS KSN, HSNN, (000S) AND DNS, WHILE (000N) MUST AGREE WITH THE SINGLE SCATTERING POLARIZATION PARAMETER (0N00).


STUDY OF INCLUSIVE REACTIONS K- P ---> ANTI-K0 X AND K- P ---> LAMBDA0 X AT 6.5-GeV/c

De Clercq, C. ; Johnson, D.P. ; Lemonne, J. ; et al.
Phys.Rev.D 19 (1979) 3197-3209, 1979.
Inspire Record 146772 DOI 10.17182/hepdata.24272

Inclusive V0 production in 6.5-GeV/c K−p interactions is studied using the ANL 12-ft-diameter hydrogen bubble chamber. The total cross sections for inclusive K¯0 and Λ0 production are σ(K¯0)=7.98±0.49 mb and σ(Λ0)=3.94±0.24 mb. Semi-inclusive differential cross sections are determined as functions of Feynman x and transverse momentum squared of the V0's and of four-momentum transfer to the V0. The average charge multiplicity, the ratio 〈nc〉D, and the correlation function f2cc for the neutrally charged hadronic system recoiling from the V0 are determined as functions of the mass of the recoiling system. Results are used to examine universal aspects of multiparticle production.

4 data tables
Table 1

No description provided.

Table 2

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Table 3

No description provided.

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