Walker, R.L.
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Experimental Upper Limit on the Photoproduction Cross-Section for the psi (3105)

Martin, J.F. ; Bolon, C. ; Lanza, R.L. ; et al.
Phys.Rev.Lett. 34 (1975) 288, 1975.
Inspire Record 91767 DOI 10.17182/hepdata.21195

The experimental upper limit for the diffractive photoproduction of the ψ(3105) is 29 nb, with 90% confidence, at an average photon energy of 18.2 GeV.

1 data table
Table 1

No description provided.


Multiple Pion Production in pi-Ne Collisions at 10.5-GeV and 200-GeV

Elliott, J.R. ; Fortney, L.R. ; Goshaw, A.T. ; et al.
Phys.Rev.Lett. 34 (1975) 607, 1975.
Inspire Record 2065 DOI 10.17182/hepdata.31340

We have measured the multiplicities of pions produced in the collisions of π mesons with neon nuclei at bombarding momenta of 10.5 and 200 GeV/c. The diffractive production of pions is clearly separable. If one excludes the diffractive part, the pion multiplicity obeys the same Koba-Nielsen-Olesen scaling as found previously for π−−p collisions. This fact would seem to indicate the validity of an energy-flux or collective-variable description of the production process. A surprisingly large number of energetic protons (> 1 GeV/c lab momentum) are found to be produced in π-Ne collisions.

1 data table
Table 1

Elastic and diffractive events removed.


Study of Vector Meson Baryon Resonance Production in pi+ p Interactions at 7.1-GeV/c

Chung, S.U. ; Protopopescu, S.D. ; Eisner, R.L. ; et al.
Phys.Rev.D 12 (1975) 693, 1975.
Inspire Record 99147 DOI 10.17182/hepdata.48154

From a large-statistics π+p experiment at 7.1 GeV/c, data are presented on the reactions π+p→ρ0Δ++(1238) and π+p→ωΔ++(1238). Cross sections, differential cross sections, and vector-meson single-density-matrix elements are presented and a general comparison of the production properties of the two reactions is given. In addition to (ρ,ω)Δ++(1238) production there is also strong evidence for production of a π+p enhancement with mass ∼ 1880 MeV, Γ∼200 MeV, and J≥72 produced in association with the ρ and ω resonances. Detailed properties of this structure are presented and its production mechanism is compared with that of the corresponding Δ(1238) reactions. This state is also observed in the reaction K+p→K*0(890)Δ++(1880) at 12.0 GeV/c, for which data are also presented.

15 data tables
Table 1

STATISTICAL ERRORS ONLY.

Table 2

No description provided.

Table 3

JACKSON FRAME.

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Study of the Energy and Charged Multiplicity Dependence of Inclusive pi- Production in pi- p Interactions Up to Fermilab Energies

Morris, W. ; Oh, B.Y. ; Parker, D.L. ; et al.
Phys.Lett.B 56 (1975) 395-399, 1975.
Inspire Record 2113 DOI 10.17182/hepdata.27878

Using new data from 100 GeV c π − interactions, we find the energy dependence of the invariant cross-section in the target fragmentation (central) region to be consistent with an A + Bs − 1 2 (C + Ds − 1 4 ) behavior. The leading particle peak near x = + 1 exhibits a width in x which becomes smaller with increasing energy and an integrated cross section which is approximately energy independent.

1 data table
Table 1

No description provided.


Neutral Particle Production in pi+ p and p p Collisions at 100-GeV/c

Alston-Garnjost, Margaret ; Erwin, J. ; Klems, J.H. ; et al.
Phys.Rev.Lett. 35 (1975) 142, 1975.
Inspire Record 98682 DOI 10.17182/hepdata.21191

We have measured the inclusive cross sections for γ, Ks0, Λ, and Λ¯ production in π+p and pp interactions at 100 GeV/c and compared various inclusive distributions of the produced γ and Ks0.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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A20 Production by Charge Exchange in pi+ n Interactions at 4-GeV/c

Emms, M.J. ; Jones, G.T. ; Kinson, J.B. ; et al.
Phys.Lett.B 58 (1975) 117-120, 1975.
Inspire Record 98783 DOI 10.17182/hepdata.27809

A partial wave analysis of the reaction π + n → π + π − π 0 p yields an A 0 2 production cross section of 225 ± 30μb for momentum transfer squared < 1 (GeV/ c ) 2 ; the differential cross-section and density matrix are presented and compared with ω 0 production in the light of theoretical models.

2 data tables
Table 1

Axis error includes +- 10/10 contribution.

Table 2

ASSUMING NO POPULATION OF HELICITY 2 DENSITY MATRIX ELEMENTS IN T-CHANNEL FRAME. THIS MM = 1+, 1-, 2+, 2- NOTATION REFERS TO THAT SUM OR DIFFERENCE OF HELICITY M DENSITY MATRIX ELEMENTS CORRESPONDING ASYMPTOTICALLY TO NATURAL (+) OR UNNATURAL (-) PARITY EXCHANGE.


Observation of a High-Mass Delta++ Produced in Association with K*, rho and omega

Chung, S.U. ; Protopopescu, S.D. ; Eisner, R.L. ; et al.
Phys.Lett.B 57 (1975) 384-388, 1975.
Inspire Record 98501 DOI 10.17182/hepdata.27841

Strong evidence is presented for quasi-two-body production of a π + p enhancement with mass 1881±6MeV and width 219±23MeV, recoiling off vector mesons ϱ O and ω from π + p interactions at 7.1 GeV/ c and K * o (890) from K + p interactions at 12 GeV/ c . The most probable J P assignment for this object is 7/2 + , making it a likely candidate for the Regge recurrence of Δ(1236).

2 data tables
Table 1

JACKSON FRAME.

Table 2

JACKSON FRAME.


Inclusive Delta++ Production in pi+ p and p p Interactions at 100-GeV/c and the Average Multiplicity of pi+ pi- Scattering

Erwin, J. ; Kass, R.D. ; Klems, J.H. ; et al.
Phys.Rev.Lett. 35 (1975) 980, 1975.
Inspire Record 2415 DOI 10.17182/hepdata.21100

Inclusive Δ++(1236) production in π+p and pp interactions is consistent with one-pion exchange. The average charged multiplicity recoiling from the Δ++ is studied as a function of missing mass, M2, for both interactions.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Total Cross-Sections of pi+-, K+-, p, and anti-p on Protons and Deuterons Between 23-GeV/c and 280-GeV/c

Carroll, A.S. ; Chiang, I.-H. ; Kycia, T.F. ; et al.
Phys.Lett.B 61 (1976) 303-308, 1976.
Inspire Record 98502 DOI 10.17182/hepdata.27688

New measurements are reported of total cross sections for π ± , K ± , p and p on protons and deuterons at 11 momenta between 23 and 280 GeV/ c .

24 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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The Production of the Omega0 Meson in the Reaction pi+ d --> p (Spectator) p Omega0 at 4-GeV/c

Emms, M.J. ; Kinson, J.B. ; Stacey, B.J. ; et al.
Nucl.Phys.B 98 (1975) 1-28, 1975.
Inspire Record 100077 DOI 10.17182/hepdata.31856

The reaction π + n → ω 0 p has been studied at 4 GeV/ c giving a total cross section of 313 ± 26 μ b. The sample of about 3500 ω 0 events produced in the forward direction has been used to determine the differential cross section and the spin density matrix elements. The effective trajectory for unnatural parity exchange has been determined by a comparison of ϱ 00 d σ /d t at different energies. A comparison of ϱ 00 d σ /d t has been made with the similar data for ϱ 0 production in this experiment allowing π-B exchange degeneracy and ϱ-ω interference to be investigated. These methods result in an unnatural trajectory consistent with that expected for the B-meson. A further study of ϱ-ω interference has been made by comparing the reactions π + n → ω 0 p and π − p → ω 0 n at similar energies. Our results on ω and ϱ production are combined with data on K ∗0 and K ∗0 production at 4 GeV/ c and an SU(3) sum rule relating the production of these four mesons is shown to be satisfied.

13 data tables
Table 1

ASSUMING PREDOMINANTLY NUCLEON SPIN FLIP.

Table 2

No description provided.

Table 3

No description provided.

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