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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 <y>∼2.6 and <pT>∼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.

Precise Measurement of the Xi0 Magnetic Moment

Cox, P.T. ; Dworkin, J. ; Overseth, O.E. ; et al.

Phys.Rev.Lett. 46 (1981) 877-880, 1981.

Inspire Record 169860 DOI 10.17182/hepdata.20645

The magnetic moment of the Ξ0 hyperon has been measured to be μΞ0=−1.253±0.014 nuclear magnetons. A new measurement of μΛ is also reported.

1 data table

Table 1

No description provided.

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.

SMALL MOMENTUM TRANSFER K- p CHARGE EXCHANGE SCATTERING AT 30-GeV/c

The Serpukhov-Brussels-Annecy(LAPP) collaboration Binon, F. ; Lagnaux, J.P. ; Roosen, R. ; et al.

Nuovo Cim.A 64 (1981) 89-100, 1981.

Inspire Record 164179 DOI 10.17182/hepdata.49654

The$K^ -p \to \bar K^0 n$ charge exchange differential cross-section has been measured at 30 GeV/c with high statistical accuracy and high angular resolution. The experiment was made at the IHEP 70 GeV accelerator, by using a hodoscope hadron calorimeter to detect KL0. The cross-section shows a dip at small |t|, which indicates a dominance of spin-flip amplitudes in ρ and A2 exchanges in thet-channel.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

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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Experimental Limits on the Strength of Weak Neutral Currents in Lepton Pair Production at {PETRA} Energies

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.

Phys.Lett.B 99 (1981) 281-286, 1981.

Inspire Record 156813 DOI 10.17182/hepdata.27121

The processes e + e − → e + e − and μ + μ − have been studied at PETRA using the JADE detector. The data, which were collected at s -values of up to 1300 GeV 2 have been analysed in terms of an electro-weak extension of QED to obtain values for the weak vector and axial vector couplings in the lepton sector. The values obtained agree with the predictions of the standard Salam-Weinberg model and the data are further analysed in terms of this model to obtain the limits 0.10 < sin 2 ϑ w < 0.40 (68% CL). The mass of the neutral weak gauge boson is deduced to be greater than 51 GeV/ c 2 .

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

Experimental Study of Neutral Current and Charged Current Neutrino Cross-Sections

The CHARM collaboration Jonker, M. ; Panman, J. ; Udo, F. ; et al.

Phys.Lett.B 99 (1981) 265, 1981.

Inspire Record 156267 DOI 10.17182/hepdata.27136

Samples of 9200 muon-neutrino and 3800 muon-antineutrino interactions on nuclei were obtained with the fine-grain calorimeter of the CHARM Collaboration at the CERN 200 GeV narrow-band neutrino beam. The interactions were classified as either neutral-current or charged-current processes on an event-by-event basis. Neutral-current and charged-current cross sections in neutrino and antineutrino interactions are presented. From these results we deduce a statistically significant contribution of right-handed coupling to the neutral hadronic current, and a value of the electroweak mixing angle corresponding to sin 2 θ = 0.220 ± 0.014.

4 data tables

Table 1

Measured charged current total cross section.

Table 2

Measured charged current total cross section.

Table 3

No description provided.

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