Amato, S.
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POLARIZATION OF RECOIL NEUTRONS FROM SINGLE PION PHOTOPRODUCTION OFF PROTONS IN THE RESONANCE REGION

Egawa, K. ; Ishii, T. ; Daigo, M. ; et al.
Nucl.Phys.B 188 (1981) 11-28, 1981.
Inspire Record 171265 DOI 10.17182/hepdata.34257

The polarization of the recoil neutrons from the reaction γ p→ π + n was measured at a c.m. angle of 105° for incident photon energies between 675 and 1125 MeV. A scattered π + meson and a recoil neutron were detected in coincidence with a magnetic spectrometer and a neutron polarimeter system using liquid hydrogen. Results are compared with recent phenomenological analyses and the other existing data measured by the double polarization measurement technique.

1 data table
Table 1

ERRORS ARE STATISTICAL ONLY.


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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Inclusive $\phi$ Meson Production in 93-{GeV} and 63-{GeV} Hadron Interaction

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.
Nucl.Phys.B 186 (1981) 205-218, 1981.
Inspire Record 10281 DOI 10.17182/hepdata.7855

The inclusive reactions h+p→ φ +X, (h= π ±, ,K ± ,p ± ), are studied for 0⪅ x F ⪅0.3 and p ⊥ ⩽ 1 GeV at 93 and and 63 GeV incident momentum. Differential cross sections d σ /d p ⊥ 2 and dσ /d x F are presented and are compared with predictions of the naive parton model.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Charged Hadron Production in $e^+ e^-$ Annihilation in the $\Upsilon$ and $\Upsilon^\prime$ Region

The LENA collaboration Niczyporuk, B. ; Zeludziewicz, T. ; Chen, K.W. ; et al.
Z.Phys.C 9 (1981) 1, 1981.
Inspire Record 164397 DOI 10.17182/hepdata.1354

Charged hadron production ine+e− annihilation is studied in the 7 to 10 GeV CM energy region and at the Υ (9.46) and Υ′ (10.01) resonances with the LENA detector at DORIS. The statistical moments of the charged multiplicities are studied. The data show KNO scaling behaviour and suggest the presence of long range correlations. An average charged multiplicityrise of Δn(Υ)=0.55±0.19 and Δn(Υ′)=1.26±0.29 over the continuum is observed for the Υ and Υ′ direct decays. The jet structure of the Υ and Υ′ direct decays is investigated using the charged particles. The polar angular distributions of the jet axis behave like 1+α(T) cos2θ with 〈α(T)〉Υ=0.7±0.3 and 〈α(T)〉Υ′=0.6±0.4. The 〈α(T)〉Υ value is in agreement with the QCD vector gluon assignment and excludes scalar gluons by more than four standard deviations.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Production of Vector and Tensor Mesons in Proton Proton Collisions at $\sqrt{s}=52$.5-{GeV}

The Annecy(LAPP)-CERN-College de France-Dortmund-Heidelberg-Warsaw collaboration Drijard, D. ; Fischer, H.G. ; Geist, Walter M. ; et al.
Z.Phys.C 9 (1981) 293, 1981.
Inspire Record 164535 DOI 10.17182/hepdata.14085

Inclusive production of ϱ0,f, andg0 mesons and ofKs0,K*0 (892), ϕ andK*0(1430)mesons has been measured at ∼2.6 and ∼1.1 GeV/c in proton-proton interactions at\(\sqrt s= 52.5\) GeV. The negative particle from the two-body decays of these resonances were identified by a threshold Cerenkov counter and used for triggering. Starting from the measured differential cross section, total inclusive cross sections for the vector and tensor mesons were determined using various parametrizations for they andpT dependence of the differential cross section. The experimental results are discussed in the framework of production models based on the parton picture. The strangeness suppresion factor λ=(0.30±0.10) due toSU(3) symmetry breaking of the quark sea is derived.

1 data table
Table 1

No description provided.


Inclusive Particle Production in $\pi^- N$ Interactions at High-energies

Abramowicz, H. ; Doroba, K. ; Kossakowski, R. ; et al.
Z.Phys.C 7 (1981) 199-208, 1981.
Inspire Record 166695 DOI 10.17182/hepdata.14106

Results on inclusive particle production in π−n interactions at 21, 205 and 360 GeV/c are presented. The invariant cross sections in both neutron fragmentation and central regions are found to be equal within errors to the corresponding cross sections for π−p collisions and exhibit the same energy dependence. A strong energy dependence of the invariant cross section ratios of negative and positive pions is observed. There is also an indication of transverse momentum dependence of these ratios. The η− correlations in the neutron fragmentation region show little variation with energy and are in agreement with the predictions of the naive quark recombination scheme.

1 data table
Table 1

DATA ON MULTIPLICITY ARE OBTAINED BY AVERAGING OVER ALL THE TOPOLOGIES EXCEPT THE ONE-PRONG ONE.


Charged Pion Production in 70-{GeV}/$c K^+ P$ Interactions

Barth, M. ; De Clercq, C. ; De Wolf, E.A. ; et al.
Z.Phys.C 7 (1981) 187-198, 1981.
Inspire Record 166694 DOI 10.17182/hepdata.14086

Inclusive charged pion production is studied in an exposure of BEBC, filled with hydrogen, to an incidentK+ beam of 70 GeV/c. Total cross sections for pion production and inclusive longitudinal and transverse momentum distributions of π−'s and of positive particles are presented and compared with data at lower energies. Earlier evidence for scaling in the fragmentation regions is confirmed. The central region π− cross section increases proportionally topLAB−1/4; positive particles show almost no energy dependence atx=0. Particle ratios π+/π− are studied as a function ofx andy* and a comparison with 70 GeV/cK−p data is made. Analysis of structure functions for (ππ) pairs and of particle production associated with π± triggers at large |x| in the context of quark/parton models, provides qualitative evidence for the diquark-quark structure of the proton.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Direct Experimental Reconstruction of the $P P$ Elastic Scattering Matrix at 579-{MeV}

Aprile, E. ; Eisenegger, C. ; Hausammann, R. ; et al.
Phys.Rev.Lett. 46 (1981) 1047-1050, 1981.
Inspire Record 169865 DOI 10.17182/hepdata.20658

We have made, for the first time, a direct reconstruction of the pp elastic-scattering matrix at 579 MeV from a series of experiments performed at the Schweizerisches Institut für Nuklearforschung polarized-beam line. Fifteen observables consisting of the polarization, two-spin correlation and transfer parameters, and three-spin parameters were measured at seven angles between 66° and 90° (c. m.). The experimental results and reconstructed amplitudes are presented and compared to phase shift analysis.

2 data tables
Table 1

No description provided.

Table 2

VALUES OF PRECESSION ANGLE O. OBSERVABLES ARE RELATED BY THE FORMULA, (OABC) = (S'ABC)*COS(O) + (K'ABC)*SIN(O).


TOPOLOGY AND CHARGED MULTIPLICITY OF HADRONIC EVENTS IN THE ENERGY REGION OF THE UPSILON AND UPSILON' RESONANCES. (IN GERMAN)

Schwarz, Andreas S. ;
Hamburg Desy - INTERNAL REP. LENA-81-03 (81,REC.SEP.) 178p, 1981.
Inspire Record 171276 DOI 10.17182/hepdata.43836

None

2 data tables
Table 1

OBSERVED, UNCORRECTED, AVERAGE VALUES FOR SPHERICITY AND THRUST.

Table 2

AVERAGE CHARGED MULTIPLICITY - SEE B. NICZYPORUK ET AL., ZP C9, 1 (1981).


Search for Narrow Resonances in $e^+ e^-$ Annihilation at $c$.m. Energies Between 33.0-{GeV} and 36.72-{GeV}

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 100 (1981) 364-366, 1981.
Inspire Record 164319 DOI 10.17182/hepdata.45224

A search for narrow resonances in e + e − annihilation between 33.00 and 36.72 GeV is reported. No evidence is found for the existence of such states. The 90% confidence upper limit on the integrated resonance cross section is determined to be 28 nb MeV, a value significantly below that expected for the lowest t t bound state.

2 data tables
Table 1

AVERAGE R VALUE THROUGHOUT ENERGY RANGE. SYSTEMATIC ERROR IS CONSERVATIVE AND WILL BE IMPROVED.

Table 2

R VALUES AT 20 MEV STEPS. DATA TAKEN FROM TABLE IN THE PREPRINT.