Busnello, R.
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A Study of the Charge Exchange Reaction p p --> n Delta++ (1232) at ISR Energies

de Kerret, H. ; Nagy, E. ; Orr, R.S. ; et al.
Phys.Lett.B 69 (1977) 372-376, 1977.
Inspire Record 120459 DOI 10.17182/hepdata.27539

We report on a study of the charge-exchange reaction pp → nΔ ++ (1232) at the CERN intersecting storage rings (ISR) in the energy range √ s = 23 to 53 GeV. From our analysis of the energy dependence of the total cross-section, of the differential cross-section d σ /d t and of the decay angular distributions we find evidence that pion exchange is dominant up to √ s = 23 GeV and that ( ϱ +A 2 ) exchange dominates the reaction for √ s ⩾ 30 GeV, as described by simple Regge-pole models.

6 data tables
Table 1

THE ERRORS ARE DUE TO STATISTICAL ERRORS AND BACKGROUND SUBTRACTION ERRORS COMBINED IN QUADRATURE.

Table 2

THE ERRORS ARE DUE TO STATISTICAL ERRORS AND BACKGROUND SUBTRACTION ERRORS COMBINED IN QUADRATURE.

Table 3

No description provided.

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The Low Mass K pi System in K- p --> anti-K pi n Reactions at 14.3-GeV/c

Spiro, M. ; Barloutaud, R. ; Borg, A. ; et al.
Nucl.Phys.B 125 (1977) 162-188, 1977.
Inspire Record 5199 DOI 10.17182/hepdata.35407

We present experimental results and a partial-wave analysis of the low-mass ( K π) 0 systems produced in the reactions K − p → K π N at 14.3 GeV/ c . The main results concern the production mechanisms of the K ∗ (890) and K ∗ (1420) . We also extract the s-wave component of the K π system as a function of mass.

5 data tables
Table 1

THE ERRORS QUOTED (EXCEPT FOR THE FIRST REACTION) ARE MAINLY AN ESTIMATE OF THE SYSTEMATIC UNCERTAINTIES.

Table 2

No description provided.

Table 3

No description provided.

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A Partial Wave Analysis of the 3 pi System in the Reaction K- p --> pi+ pi- pi0 Lambda at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Cerrada, M. ; Wagner, F. ; Chaloupka, V. ; et al.
Nucl.Phys.B 126 (1977) 241, 1977.
Inspire Record 119497 DOI 10.17182/hepdata.35366

A partial-wave analysis of the (3 π ) 0 system produced peripherally in the reaction K − p → π + π − π 0 Λ at 4.2 GeV/ c is presented. The observation of the weak Λ decay allows a determination of all the transversity production amplitudes except for two phases. The production of known resonances having decay modes other than 3 π is used to test the isobar model ansatz. Significant ω(783), φ(1020) and A 2 (1310) production is observed. The spin parity of the ω ∗ (1675) is established as 3 − . No evidence for production of other resonances, such as axial vector-mesons, is found.

1 data table
Table 1

No description provided.


Analysis of the omega pi- System Produced in the Reaction pi- p --> pi- pi- pi+ pi0 p at 11.2-GeV/c

Gessaroli, R. ; Quareni-Vignudelli, A. ; Berti, S. ; et al.
Nucl.Phys.B 126 (1977) 382-396, 1977.
Inspire Record 119128 DOI 10.17182/hepdata.41905

The ωπ − mass spectrum, in the reaction π −p → ωπ − pat 11.2 GeV/ c , shows the production of the B − meson with a cross section of 27 ± 5 μb as well as a clear enhancement around 1670 MeV. In the differential cross section for B − production, there is a strong forward peak and a change of slope at t ' t 0.2 GeV 2 .

3 data tables
Table 1

CORRECTED FOR BACKGROUND AND OMEGA TAILS.

Table 2

No description provided.

Table 3

ABS(D-WAVE/S-WAVE) = 0.4 +- 0.1 FOR B DECAY.


Study of the Reactions pi+ p --> pi0 Delta++ (1236), eta Delta++ (1236) and eta-prime Delta++ (1236) at 16-GeV/c

The Aachen-Berlin-Bonn-CERN-Cracow-Heidelberg collaboration Honecker, R. ; Laven, H. ; Becker, L. ; et al.
Nucl.Phys.B 131 (1977) 189-208, 1977.
Inspire Record 122492 DOI 10.17182/hepdata.35195

The reactions π + p giving π 0 Δ ++ (1236), η (549) Δ ++ (1236) and η ′(958) Δ ++ (1236) are studied at 16 GeV/ c . Cross sections, differential cross sections and Δ ++ (1236) spin density matrix elements are presented. The π 0 Δ ++ (1236) differential cross section d σ d t′ indicates a dip towards t ′ = 0 and has a minimum at t ′ ≅ 0.6 GeV 2 . The Δ ++ (1236) spin density matrix elements are consistent with the predictions of the Stodolsky-Sakurai model, except perhaps near the forward direction. For ηΔ ++ (1236), the differential cross section d σ d t′ turns over in the forward direction and presents no further structure. SU(3) sum rules are tested and found to be approximately satisfied. The data agree with factorization of ϱ exchange. The effective A 2 trajectory is calculated and found to be consistent with that reported from the reaction π − p → η n.

7 data tables
Table 1

No description provided.

Table 2

NORMALIZED TO THE TOTAL CROSS SECTION OF 49 MUB.

Table 3

No description provided.

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Inelastic Photoproduction of omega and rho+- Mesons

Nelson, C.A., Jr. ; May, E.N. ; Abramson, J. ; et al.
Phys.Rev.D 17 (1978) 647, 1978.
Inspire Record 4373 DOI 10.17182/hepdata.24401

We report measurements of inelastic photoproduction of ω and ρ± mesons from hydrogen and deuterium at incident photon energies in the range 7.5-10.5 GeV. For ωΔ and ρ−Δ++ production, differential cross sections dσdt′ and spin density matrices are presented. For higher missing masses the cross sections dσdMX2 and invariant structure functions F(x) are also given. The data are compared to a one-pion-exchange model. We conclude that pion exchange is dominant for inelastic ω photoproduction, but unimportant for ρ±.

4 data tables
Table 1

CROSS SECTION PER NUCLEON FOR COMBINED HYDROGEN AND DEUTERIUM DATA ALLOWING FOR A GLAUBER CORRECTION FACTOR OF 0.88 FOR THE DEUTERIUM CROSS SECTIONS.

Table 2

HYDROGEN AND DEUTERIUM DATA COMBINED BY AVERAGING.

Table 3

OBTAINED BY EXTRAPOLATING A FIT TO D(SIG)/DT OVER -T = 0 TO 0.52 GEV**2.

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Phi-Meson Production in the Reactions pi+- n --> K- K+ n at 6-GeV/c

Cohen, Daniel H. ; Ayres, D.S. ; Diebold, R. ; et al.
Phys.Rev.Lett. 38 (1977) 269, 1977.
Inspire Record 110508 DOI 10.17182/hepdata.21019

A sample of 1200 ϕ mesons produced in the Zweig-rule-forbidden reactions π±N→ϕN shows a flat t distribution (slope=1.7 ± 0.2 GeV−2) and a cross section suppressed by 0.0032±0.0004 relative to π−p→ωn. Natural-parity-exchange ω and ϕ production have similar t dependences, while ω and ϕ production by unnatural-parity exchange differ markedly. Interference between the ϕ and the underlying K¯K S wave indicates substantial nucleon-spin incoherence between the amplitudes for ϕ and S-wave production.

3 data tables
Table 1

Axis error includes +- 10/10 contribution (RES-DEF(RES=PHI,BACK=CORRECTED)).

Table 2

Axis error includes +- 10/10 contribution (RES-DEF(RES=PHI,BACK=CORRECTED)).

Table 3

STATISTICAL ERRORS ONLY.


Backward Photoproduction of rho0 and f Between 2.8-GeV and 4.8-GeV

Clifft, R.W. ; Dainton, J.B. ; Gabathuler, E. ; et al.
Phys.Lett.B 64 (1976) 213-216, 1976.
Inspire Record 109693 DOI 10.17182/hepdata.27627

A measurement of backward photoproduction of charged pion pairs on protons is reported. The pion pair mass spectrum shows strong ϱ ° and f production. Data are presented on the u and s dependence for ϱ O and f, together with the decay polarisation for the ϱ O .

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

AVERAGED OVER U RANGE OF EXPERIMENT. NO EVIDENCE FOR ANY LARGE S-WAVE CONTRIBUTION TO THE PI PI SYSTEM IN THE RHO0 MASS REGION (RHO(0S) < -0.03 +- 0.13). U CHANNEL FRAME: Z AXIS IN INCIDENT PROTON DIRECTION IN THE DIPION REST FRAME.


Study of A2- --> eta pi- in the Reaction pi- p --> pi- pi- pi+ pi0 p at 11.2-GeV/c

The Bologna-Florence-Genoa-Milan-Oxford-Pavia collaboration Forino, A. ; Gessaroli, R. ; Cartacci, A.M. ; et al.
Nuovo Cim.A 35 (1976) 465, 1976.
Inspire Record 109786 DOI 10.17182/hepdata.37635

The analysis of A2−→ηπ− at 11.2 GeV/c confirms that A2− is essentially produced by natural-parity exchange. In the differential cross-section as a function oft′ there is evidence of the dip at smallt′ values. The branching ratio (A2→ηπ)/(A2→ϱπ) is 0.18±0.05.

3 data tables
Table 1

No description provided.

Table 2

NUMERICAL VALUES SUPPLIED BY G. THOMPSON. 100 EVENTS IN A2 REGION DEFINED BY 1.18 < M(ETA PI-) < 1.44 GEV.

Table 3

ROUGH BACKGROUND SUBTRACTION TO REMOVE NON-TRUE ETA EVENTS. FIRST THREE DENSITY MATRIX COMBINATIONS ARE NATURAL-PARITY EXCHANGE, THE REMAINDER BEING UNNATURAL-PARITY EXCHANGE.


Some 0- 1/2+ and 0- 3/2+ Final States in K- p Reactions at 14.3-GeV/c

Chaurand, B. ; Drevillon, B. ; Gago, J.M. ; et al.
Nucl.Phys.B 117 (1976) 1, 1976.
Inspire Record 109200 DOI 10.17182/hepdata.35604

We present data on K − p reactions leading to the final states K 0 n , π 0 Λ, ηΛ, η'Λ, π − Σ + , K 0 Δ 0 (1230), and π − Σ + (1385) from a bubble chamber experiment at 14.3 GeV/ c K − lab momentum. Total and differential cross sections, Λ and Σ ∓ polarisations in π 0 Λ and π − Σ + final states as well as the Σ + (1385) density matrix elements are given.

9 data tables
Table 1

NORMALIZED TO A TOTAL CROSS SECTION OF 21.5 +- 0.2 MB (GALBRAITH ET AL, PR 138B, 913 (1965)).

Table 2

No description provided.

Table 3

No description provided.

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