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A SEARCH FOR NARROW STATES IN ANTI-NEUTRON PROTON TOTAL AND ANNIHILATION CROSS-SECTIONS NEAR ANTI-N N THRESHOLD

Armstrong, T. ; Chu, C. ; Clement, J.C. ; et al.

Phys.Lett.B 175 (1986) 383-386, 1986.

Inspire Record 236704 DOI 10.17182/hepdata.30241

The n̄p total and annihilation cross section have been measured from near N̄N threshold (1880 MeV) to 1940 MeV with RMS resolution ranging from 0.08 MeV (1880 MeV) to 6.7 MeV (1940 MeV). No significant narrow meson structures were seen, with 90% CL upper limits of 40–180 mb-MeV on σΓ for states with width less than our resolution. Combined with increasing unitarity bounds on σ as one approaches threshold, these limits confine widths of possible predicted states below 1900 MeV to less than ∼ 1 MeV.

1 data table

Table 1

No description provided.

Investigation of the Reaction $e^+ e^- \to \eta \pi^+ \pi^-$ in the Energy Range Up to 1.4-{GeV}

Druzhinin, V.P. ; Dubrovin, M.S. ; Eidelman, S.I. ; et al.

Phys.Lett.B 174 (1986) 115-117, 1986.

Inspire Record 234174 DOI 10.17182/hepdata.30258

The reaction e + e − → ηπ + π − has been studied with the Neutral Detector in the CM energy range 1.05–1.40 GeV at VEPP-2M. At the maximum energy the cross section exceeds the prediction of the vector dominance with one ϱ(770). The following upper limits for the electron width times branching ratio into ηπ + π − have been obtained for a resonance with a mass of 1.28 GeV and width of 0.08 GeV observed with the Omega-spectrometer at CERN: Λ ee · B ηππ < 9 eV, and for a ϱ′(1250) with a mass of 1.26 GeV and width of 0.125 GeV: Λ ee · B ηππ < 14 eV at 90% confidence level.

1 data table

Table 1

Axis error includes +- 10/10 contribution (RES-DEF(RES=ETA,DEF=530<M(2GAMMA)<570 MEV,BACK=CORRECTED)).

Observation of Double $\phi$ Meson Production in the Central Region for the Reactions $\pi^+ P \to \pi^+ (K^+ K^+ K^- K^-$) $P$ and $P P \to P (K^+ K^+ K^- K^-$) $P$ at 85-{GeV}/c

The ATHENS-BARI-BIRMINGHAM-CERN collaboration Armstrong, T.A. ; Bloodworth, I.J. ; Carney, J.N. ; et al.

Phys.Lett.B 166 (1986) 245-248, 1986.

Inspire Record 228698 DOI 10.17182/hepdata.30307

The reactions π + p → π + ( K + K + K − K − ) p and pp → p ( K + K + K − K − ) p in which the K + K + K − K − system is centrally produced have been studied at 85 GeV c . Evidence is found for φφ production. The relative rates for production of φφ , φK + K − and K + K + K − K − have been determined.

1 data table

Table 1

No description provided.

TOTAL, ELASTIC AND INCLUSIVE SINGLE DIFFRACTIVE CROSS-SECTIONS IN ALPHA-ALPHA COLLISIONS AT THE CERN INTERSECTING STORAGE RINGS

Lloyd Owen, D. ; Paternoster, G. ; Patricelli, S. ; et al.

Nucl.Phys.B 274 (1986) 685-706, 1986.

Inspire Record 227125 DOI 10.17182/hepdata.33694

We present measurements of the total interaction cross section and of the single-diffractive dissociation cross section in αα collisions at √ s = 126 GeV. The result obtained for the total cross section, σ tot = (315±18) mb, is a substantial improvement on the precision of earlier measurements. Earlier elastic data were re-analysed, incorporating, through the optical theorem, the present σ tot measurement, resulting in improved determinations of the forward slope, b − t <0.07 = (87±4) GeV −2 , and of the integrated elastic cross section, σ el = (58±6) mb. The single-diffractive differential cross section falls exponentially with momentum transfer at small values of t with a slope b sd = (19.3 ± 0.6) GeV −2 . The integrated single-diffractive cross section is σ sd = (16.6±2.5) mb. The topology of charged tracks resulting from the disintegration of the α in single-diffractive events reveals a two-component distribution. The cross section data are compared with multiple-scattering models.

2 data tables

Table 1

Total cross section by total rate method. Systematic errors included.

Table 2

Reanalysis using data from ISR experiments R-418, and R-807.

MEASUREMENT OF THE SPIN CORRELATION PARAMETER A(00NN) AND OF THE ANALYZING POWER FOR P P ELASTIC SCATTERING IN THE ENERGY RANGE FROM 0.5-GEV TO 0.8-GEV

Bystricky, J. ; Chaumette, P. ; Deregel, J. ; et al.

Nucl.Phys.B 262 (1985) 727-743, 1985.

Inspire Record 227731 DOI 10.17182/hepdata.33710

The spin correlation parameter A oonn and the analyzing powers A oono and A ooon were measured simultaneously, in the energy range 0.5–0.8 GeV and in the angular region 40°–80° CM. The experiment used the polarized proton beam of SATURNE II and the Saclay frozen spin polarized target.

15 data tables

Table 1

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Table 2

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A Comparison of the Energy Distributions of Hadrons Produced in Deep Inelastic Scattering of Muons on Hydrogen and Deuterium Targets

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.

Z.Phys.C 31 (1986) 175, 1986.

Inspire Record 227131 DOI 10.17182/hepdata.1817

The energy distribution of inclusive hadrons produced by 280 GeV muons on hydrogen and deuterium targets are compared. The sum of the scaled energy distributions of the positive and negative hadrons is found to be the same for the two targets. The difference of these distributions is observed to factorise inx andz and thez-dependence is found to be independent of the target type and have a form (1−z)2.1±0.2. The net charge of the hadronic jet is positive at highx even in the case when the scattering takes place on the neutron. These results are in good agreement with the expectations of the Quark Parton Model.

53 data tables

Table 1

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