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Observation of Longitudinal Event Structure in Proton Diffractive Dissociation at the {ISR}

The R608 collaboration Smith, A.M. ; Meritet, L. ; Reyrolle, M. ; et al.

Phys.Lett.B 167 (1986) 248-254, 1986.

Inspire Record 219984 DOI 10.17182/hepdata.30272

We study the internal structure of a forward-going pπ + π − π + π − system, with invariant mass in the range 2.5-4 GeV, produced through diffractive dissociation of a beam proton at the ISR. The shape of the system, as seen in its center-of-mass, deviates strongly from isotropic phase space and possesses, rather, a longitudinal structure with a major axis along the incoming proton direction. The final state proton momentum is aligned in the direction of the incoming proton, an effect which becomes more pronounced with increasing diffractive mass.

2 data tables

Table 1

Acceptance corrected distribution of momentum transfer to the diffractive (p-4pi) system. Data requested from authors.

Table 2

No description provided.

Observation of Three 2++ Resonances in the Glueball Enhanced Channel $\pi^- p \to \phi \phi n$

Etkin, A. ; Foley, K.J. ; Longacre, R.S. ; et al.

Phys.Lett.B 165 (1985) 217-221, 1985.

Inspire Record 218668 DOI 10.17182/hepdata.30309

We present data on 3652 analyzed events of the reaction π - p → φφn at 22 GeV/ c . A partial wave analysis has been performed on the φφ system. The results are well represented by three resonances all with quantum numbers I G J PC = 0 + 2 ++ . The absence of the Okubo-Zweig-Iizuka suppression observed in this reaction, the selection of only three J PC =2 ++ states ( g T , g T′ , and g T ″ ) which comprise virtually all of the cross section, and the large φφn signal over a very different φK + K - n background are all well explained if these states are produced by 1–3 glueballs (i.e. multigluon resonances).

1 data table

Table 1

Slope indicates pion exchange process.

Study of $\eta \pi^+ \pi^-$ States in the $\rho^\prime$ (1600) Mass Region Photoproduced in the Reaction $\gamma p \to \eta \pi^+ \pi^- p$ at Photon Energies of 20-{GeV} to 70-{GeV}

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.

Z.Phys.C 30 (1986) 531, 1986.

Inspire Record 218611 DOI 10.17182/hepdata.15991

In diffractive photoproduction ofηπ+π−, the two-body substatesηρ0 andA2π are found to contribute significantly to the cross-section forηπ+π− masses below 2.4 GeV. From a spin-parity analysis the branching ratio, ρ′(1600)→ηρ/ρ′(1600)→, is determined to be <0.02 at the 68.3% confidence level. TheA2π component shows an enhancement around 1.7 GeV. The spin-parity analysis indicates a probable contribution to this signal from exclusive photoproduction of theg(1690).

6 data tables

Table 1

No description provided.

Table 2

Not corrected for 35% background under the eta --> gamma gamma peak.

Table 3

Not corrected for 35% background under the ETA --> GAMMA GAMMA peak.

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EXCLUSIVE rho0 PRODUCTION IN DEEP INELASTIC MUON PROTON SCATTERING

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

Phys.Lett.B 161 (1985) 203, 1985.

Inspire Record 214930 DOI 10.17182/hepdata.30353

Exclusive ϱ 0 production has been measured in 120, 200 and 280 GeV muon-proton interactions at high Q 2 (1 GeV 2 < Q 2 < 25 GeV 2 ) and W (6 GeV < W < 19 GeV). The photoproduction cross section decreases as 1/ Q 4 . A shallow t distribution, typical of a hard scattering process is observed and the ϱ 0 is found to be dominantly in the helicity zero spin state. The ϱ 0 s are mainly produced by transverse photons and s -channel helicity conservation seems to be invalid. The data cannot be described by the vector meson dominance model. These data show that at high Q 2 even exclusive ϱ 0 muoproduction is a hard scattering process and that the soft hadron-like properties of the photon have disappeared.

8 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

SYSTEMATIC ERROR ON SLOPE IN 0.8.

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A STUDY OF INELASTIC DIFFRACTION OF pi- MESON IN pi+ pi- pi- SYSTEM USING A 'LIVE' TARGET OF SILICON

Vegni, G. ; Vishnyakov, V.V. ; Zaimidoroga, O.A. ; et al.

Yad.Fiz. 43 (1986) 1480-1486, 1986.

Inspire Record 218427 DOI 10.17182/hepdata.39505

None

1 data table

Table 1

No description provided.

Measurement of Small Angle anti-Proton - Proton and Proton Proton Elastic Scattering at the CERN Intersecting Storage Rings

Amos, Norman A. ; Block, M.M. ; Bobbink, G.J. ; et al.

Nucl.Phys.B 262 (1985) 689-714, 1985.

Inspire Record 214689 DOI 10.17182/hepdata.33711

Antiproton-proton and proton-proton small-angle elastic scattering was measured for centre-of-mass energies s =30.6, 52.8 and 62.3 GeV at the CERN Intersectung Storage Rings. In addition, proton-proton elastic scattering was measured at s =23.5 GeV . Using the optical theorem, total cross sections are obtained with an accuracy of about 0.5% for proton-proton scattering and about 1% for antiproton-proton scattering. The measurement of the interference of the Coulomb scattering and the hadronic scattering permits a determination of the ratio of the real-to-imaginary part of the forward hadronic scattering amplitude. Also presented are measurements of the hadronic slope parameter.

13 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Real to Imaginary Ratio of the $\bar{p} p$ Forward Elastic Scattering Amplitude in the Momentum Range Between 180-{MeV}/$c$ and 590-{MeV}/$c$

Bruckner, W. ; Dobbeling, H. ; Guttner, F. ; et al.

Phys.Lett.B 158 (1985) 180-185, 1985.

Inspire Record 213992 DOI 10.17182/hepdata.30392

The real-to-imaginary ratio of the p p forward elastic scattering amplitude has been measured at the LEAR facility of CERN by the Coulomb-nuclear interference method at seven beam momenta between 181 and 590 MeV/ c . The ratio is positive at 590 MeV/ c , becomes negative below 500 MeV/ c , reaches a minimum at 260 MeV/ c and then crosses zero again at about 230 MeV/ c .

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.