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Based on our measurement of the ratio f(π − π 0 p ) f(π + π − n ) =2.07±0.05 for antiproton annihilation at rest in liquid deuterium, we find that S-wave annihilation of the antiproton on the proton or neutron into ππ is dominant. We quote a 95% confidence level upper limit of 8% for P-wave annihilation into ππ.

1 data table

Table 1

No description provided.

Determination of the Neutral Current Chiral Coupling Constants From $U(2)_L$, $U(2)_R$, $d(2)_L$ and $d(2)_R$ From a Neutrino and Anti-neutrino Deuterium Experiment

The WA25 collaboration Allasia, D. ; Angelini, C. ; Baldini, A. ; et al.

Nucl.Phys.B 307 (1988) 1-18, 1988.

Inspire Record 260699 DOI 10.17182/hepdata.33342

The ratios of neutral-current to charged-current cross sections of v and v interactions, seperately, on proton and neutron targets have been measured. The Big European Bubble Chamber (BEBC), filled with deuterium and equipped with an external muon identifier (EMI) and an internal picket fence (IPF), was exposed to the CERN SPS (anti)neutrino wide-band beam. The measured ratios are R v p= = 0.405 ± 0.024 ± 0.021 , R v n = 0.243 ± 0.013 ± 0.016, R v p = 0.301 ± 0.027 ± 0.024 and R v n = 0.490 ± 0.050 ± 0.037 . (The first error is statistical and the second systematic). From combinations of these ratios the following neutral-current chiral coupling constants have been determined: u L 2 = 0.099 ± 0.018 ± 0.008, d L 2 = 0.202 ± 0.020 ± 0.019, u R 2 = 0.020 ± 0.016 ± 0.009 and d R 2 = 0.002 ± 0.017 ± 0.010. These results agree with the predictions of the SU(2) × U(1) standard electroweak model. Assuming ϱ = 1, the corresponding value of sin 2 θ w is found to be 0.247 ± 0.029, whereas a two-parameter fit to the data yields sin 2 θ w = 0.243 ± 0.046 and ϱ = 0.996 ± 0.041.

8 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Central Collisions of 14.6-{GeV}/nucleon, 60-{GeV}/nucleon, and 200-{GeV}/nucleon $^{16}$O Nuclei in Nuclear Emulsion

Barbier, L.M. ; Freier, P.S. ; Holynski, R. ; et al.

Phys.Rev.Lett. 60 (1988) 405-407, 1988.

Inspire Record 264260 DOI 10.17182/hepdata.2969

Central collisions of O16 nuclei with the Ag107 and Br80 nuclei in nuclear emulsion at 14.6, 60, and 200 GeV/nucleon are compared with proton-emulsion data at equivalent energies. The multiplicities of produced charged secondaries are consistent with the predictions of superposition models. At 200 GeV/nucleon the central particle pseudorapidity density is 58±2 for those events with multiplicities exceeding 200 particles.

5 data tables

Table 1

Nucleus is average nucleus of BR-2 emulsion.

Table 2

Nucleus is average nucleus of BR-2 emulsion.

Table 3

Nucleus is average AG107/BR80 nucleus of BR-2 emulsion.

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rivet Analysis
Study of the Reaction $e^+ e^- \to K^+ K^-$ in the Energy Range 1350 $\le \sqrt{s} \le$ 2400-{MeV}

The DM2 collaboration Bisello, D. ; Busetto, G. ; Castro, A. ; et al.

Z.Phys.C 39 (1988) 13, 1988.

Inspire Record 262690 DOI 10.17182/hepdata.15622

Thee+e−→K+K− cross section has been measured from about 750 events in the energy interval$1350 \leqq \sqrt s\leqq 2400 MeV$ with the DM2 detector at DCI. TheK± form factor |FF±| cannot be explained by the ρ, ω, ϕ and ρ′(1600). An additional resonant amplitude at 1650 MeV has to be added as suggested by a previous experiment.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Increased Statistics and Observation of the $g(T$), $g(T$)-prime, and $g(T$)-prime-prime 2++ Resonances in the Glueball Enhanced Channel $\pi^- p \to \phi \phi n$

Etkin, A. ; Foley, K.J. ; Hackenburg, R.W. ; et al.

Phys.Lett.B 201 (1988) 568-572, 1988.

Inspire Record 253944 DOI 10.17182/hepdata.30006

In a new experiment we have obtained 3006 new events in the reaction π − p → φφ n, approximately doubling the statistics which now total 6658. A refined partial wave analysis of the φφ system again reveals three resonances (g T , g T′ , g T′' ) with I G J PC =0 + 2 ++ . The absence of the OZI suppression, and the observation of only three J PC =2 ++ states (g T , g T′ , g T′' ) which comprise virtually all the cross section are unusual characteristics of the data. The large φφn signal occurs over a mostly structureless and incoherent φK + K − n background. All these unusual characteristics are well explained if these states are produced by 1–3 glueballs (multigluon resonances).

2 data tables

Table 1

Total cross section plus systematic error supplied by authors.

Table 2

Absolute cross section based on total cross section of 50 +- 15 nb. Errors quoted in Table are statistical only.

Measurement and Analysis of the Reaction $\gamma \gamma \to \pi^+ \pi^- \pi^+ \pi^-$

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.

Z.Phys.C 38 (1988) 521, 1988.

Inspire Record 252632 DOI 10.17182/hepdata.1916

We have measured the cross section of four charged pion production in photon-photon interactions in the invariant mass range 1.0≦Wγγ≦3.2 GeV and up toQ2=16 GeV2. For 1.2 GeV≦Wγγ≦1.7 GeV the process is dominated by ρ0ρ0 production with a rapid rise in cross section around 1.2 GeV, well below the nominal ρ0ρ0 threshold. The observed distributions in the two particle masses and in the production and decay angles are well described by an incoherent sum of the phase-space subprocesses γγ →ρ0ρ0, →ρ0π+π−, and →π+π−π+π−. A spin-parity analysis of the ρ0ρ0 system showsJP=2+ to dominate, although 0+ is also possible forWγγ≦1.4 GeV. Negative partity states are excluded.

12 data tables

Table 1

Fractions of subprocesses from 3-parameter fit to the no-tag data.

Table 2

Fractions of subprocesses from 2-parameter fit to the no-tag data in limited energy range. The Q=1R contribution is set equal to zero.

Table 3

Fractions of subprocesses from 3-parameter fit to the single-tag data.

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ANTI-PROTON HE-4 ELASTIC SCATTERING AT 600-MEV/C. (IN RUSSIAN)

LAMBDA (1520) PRODUCTION IN NEUTRON - NUCLEON INTERACTIONS AT approximately 40-GeV NEUTRON ENERGY

DIFFRACTIVE DISSOCIATION OF NEUTRONS IN LAMBDA0 K0 ON HYDROGEN AT ABOUT 40-GeV ENERGY

PRODUCTION OF NEUTRAL STRANGE PARTICLES IN ANTI-P HE-4 ANNIHILATION AT 600-MEV/C. (IN RUSSIAN)

A Measurement of the S and $P$ Wave Content of Anti-proton Annihilation at Rest Into Two Pions in Liquid Deuterium

Determination of the Neutral Current Chiral Coupling Constants From $U(2)_L$, $U(2)_R$, $d(2)_L$ and $d(2)_R$ From a Neutrino and Anti-neutrino Deuterium Experiment

Central Collisions of 14.6-{GeV}/nucleon, 60-{GeV}/nucleon, and 200-{GeV}/nucleon $^{16}$O Nuclei in Nuclear Emulsion

rivet Analysis
Study of the Reaction $e^+ e^- \to K^+ K^-$ in the Energy Range 1350 $\le \sqrt{s} \le$ 2400-{MeV}

Increased Statistics and Observation of the $g(T$), $g(T$)-prime, and $g(T$)-prime-prime 2++ Resonances in the Glueball Enhanced Channel $\pi^- p \to \phi \phi n$

Measurement and Analysis of the Reaction $\gamma \gamma \to \pi^+ \pi^- \pi^+ \pi^-$