Ammar, R.
Inclusive
SLOPE
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Bubble Chamber Study of Photoproduction by 2.8-GeV and 4.7-GeV Polarized Photons. 1. Cross-Section Determinations and Production of rho0 and Delta++ in the Reaction gamma p --> p pi+ pi-

Ballam, Joseph ; Chadwick, G.B. ; Gearhart, R. ; et al.
Phys.Rev.D 5 (1972) 545, 1972.
Inspire Record 67165 DOI 10.17182/hepdata.3635

Photoproduction is studied at 2.8 and 4.7 GeV using a linearly polarized monoenergetic photon beam in a hydrogen bubble chamber. We discuss the experimental procedure, the determination of channel cross sections, and the analysis of the channel γp→pπ+π−. A model-independent analysis of the ρ0-decay angular distribution allows us to measure nine independent density-matrix elements. From these we find that the reaction γp→pρ0 proceeds almost completely through natural parity exchange for squared momentum transfers |t|<1 GeV2 and that the ρ production mechanism is consistent with s-channel c.m. helicity conservation for |t|<0.4 GeV2. A cross section for the production of π+π− pairs in the s-channel c.m. helicity-conserving p-wave state is determined. The ρ mass shape is studied as a function of momentum transfer and is found to be inconsistent with a t-independent Ross-Stodolsky factor. Using a t-dependent parametrization of the ρ0 mass shape we derive a phenomenological ρ0 cross section. We compare our phenomenological ρ0 cross section with other experiments and find good agreement for 0.05<|t|<1 GeV2. We discuss the discrepancies in the various determinations of the forward differential cross section. We study models for ρ0 photoproduction and find that the Söding model best describes the data. Using the Söding model we determine a ρ0 cross section. We determine cross sections and nine density-matrix elements for γp→Δ++π−. The parity asymmetry for Δ++ production is incompatible with simple one-pion exchange. We compare Δ++ production with models.

20 data tables
Table 1

FROM QUOTED TOPOLOGICAL CROSS SECTIONS. 1.44 GEV CROSS SECTION PUBLISHED PREVIOUSLY.

Table 2

No description provided.

Table 3

NO TMIN CORRECTION HAS BEEN MADE.

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Charged particle productions at 90 degrees in the center-of-mass in very high energy proton proton collisions

Banner, M. ; Hamel, J.L. ; Pansart, J.P. ; et al.
Phys.Lett.B 41 (1972) 547-551, 1972.
Inspire Record 85071 DOI 10.17182/hepdata.28219

The transverse momentum distribution at 90° of pions, protons and antiprotons have been measured at the CERN intersecting storage rings for C.M. energies between 23.2 and 52.7 GeV. In this energy range, the pion and proton distributions are almost energy independent. The antiproton production rises by a factor of two between 23.2 and 52.7 GeV.

3 data tables
Table 1

The invariant cross section was fitted by CONST*EXP(-SLOPE*PT).

Table 2

The invariant cross section was fitted by CONST*EXP(-SLOPE(C=1)*PT+SLOPE(C=2)*PT**2).

Table 3

No description provided.


Diffractive Dissociation of the Beam Particle in anti-p p Interactions at 32.1-GeV/c

The French-Soviet union & CERN-Soviet union collaborations Grard, F. ; Kesteman, J. ; Laurent, J. ; et al.
Phys.Lett.B 59 (1975) 409, 1975.
Inspire Record 98777 DOI 10.17182/hepdata.27764

We report the results of a study of the reaction p p → p + x at 32.1 GeV c , where the recoiling proton has a small laboratory momentum. The reaction is studied in the 4.5 m Mirabelle bubble chamber at Serpukhov. We compare the diffractive dissociation of the incident antiproton to other incident particles.

3 data tables
Table 1

No description provided.

Table 2

CALCULATED USING THE OPTICAL THEOREM AND THE TOTAL CROSS SECTION FOR AP P OF 46 +- 0.3 MB.

Table 3

TOPOLOGICAL AND BEAM DIFFRACTION CROSS SECTIONS WITH PLAB(FINAL STATE PROTON) < 1.1 GEV/C.


Rho0 Production in 205-GeV/c p p Interactions

Singer, R. ; Fields, T.H. ; Hyman, L.G. ; et al.
Phys.Lett.B 60 (1976) 385-388, 1976.
Inspire Record 2818 DOI 10.17182/hepdata.6484

Inclusive and semi-inclusive ρ 0 production are studied in 205 GeV/ c pp interactions. The number of ρ 0 per inelastic event is 0.33 ± 0.06, so that (13 ± 2)% of the π − are products of ϱ 0 decay. The ρ 0 are found to be produced mainly near y = 0 and tend to have larger average transverse momentum than do pions.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive Cross-Sections for 180-Degree Production of High-Energy Protons, Deuterons, and Tritons in p-Nucleus Collisions at 600-MeV and 800-MeV

Frankel, S. ; Frati, W. ; Van Dyck, O. ; et al.
Phys.Rev.Lett. 36 (1976) 642, 1976.
Inspire Record 100888 DOI 10.17182/hepdata.21102

The inclusive cross sections, measured up to large values of effective mass (≡q22ν), are well fitted by dσd3p=Bxexp(−αxp22mx). Values of Bx and αx are given for Be, C, Cu, and Ta at the incident proton energy of 600 MeV and for Ag, Ta, and Pt at 800 MeV. Extremely large dp and tp ratios and large A and q2 dependences of the relative cross sections are observed.

2 data tables
Table 1

D3(SIG)/D3(P) is fitted by the equation: CONST*exp(-SLOPE*P**2/(2*M)). CONST is presented per nucleon.

Table 2

D3(SIG)/D3(P) is fitted by the equation: CONST*exp(-SLOPE*P**2/(2*M)). CONST is presented per nucleon.


$\pi^- p$ at 205 GeV/c: Multiplicities of Charged and Neutral Particles Production of Neutral Particles

Ljung, D. ; Bogert, D. ; Hanft, R. ; et al.
Phys.Rev.D 15 (1977) 3163, 1977.
Inspire Record 111665 DOI 10.17182/hepdata.24616

A study of 205-GeV/c π−p interactions has been made with a 48 800-picture exposure in the bare Fermilab 30-inch hydrogen bubble chamber. The average number of charged particles produced per inelastic interaction is 7.99±0.06. The elastic cross section is 3.18±0.13 mb and the total cross section is 24.19±0.44 mb. The inclusive cross sections for neutral-particle production are: σ(γ)=171.3±15.3 mb, σ(KS0)=3.64±0.61 mb (x<0.3), σ(Λ)=1.71±0.34 mb (x<0.3), and σ(Λ¯)=0.59±0.23 mb (x<0.1). The average number of π0's produced per inelastic collision is consistent with a linear rise with the number of charged particles, and about equal to the number of produced π− or π+. The average number of K0's, Λ's, and Λ¯'s is consistent with very little dependence on the number of charged particles. General characteristics of neutral-particle production are presented and compared with other experiments. For each topology the produced neutral energy is ∼13 of the incident energy.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Cross-Sections of Annihilation and Inelastic Final States for anti-p p Interactions at 9.1-GeV/c

The LIVERPOOL-STOCKHOLM collaboration Gregory, P.S. ; Johnson, P. ; Mason, P. ; et al.
Nucl.Phys.B 119 (1977) 60-76, 1977.
Inspire Record 123859 DOI 10.17182/hepdata.8340

Topological and channel cross sections are given for annihilation and inelastic final states produced in p p interactions at 9.1 GeV/c. Cross sections for prominent resonances in specific channels and charged pion, ϱ 0 and Δ ++ inclusive cross sections are also presented.

6 data tables
Table 1

No description provided.

Table 2

FITTED FORWARD D(SIG)/DT = 153 +- 8 MB/GEV**2.

Table 3

CHANNEL CROSS SECTIONS FOR 2, 4, 6, AND 8 PRONG REACTIONS.

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Production of Multi - Pion Systems With Large Longitudinal Momentum at the {CERN} {ISR}

Lockman, William S. ; Meyer, T. ; Rander, J. ; et al.
Phys.Rev.Lett. 41 (1978) 680-683, 1978.
Inspire Record 6695 DOI 10.17182/hepdata.20814

Inclusive cross sections are presented for 2π and 3π systems with large longitudinal x at the highest intersecting storage ring energies (s=53 GeV for 2π; s=53 and 62 GeV for 3π). The ratio π+π−π−π− rises sharply with increasing x similar to the ratio K+K−, as expected in a quark-model interpretation.

2 data tables
Table 1

The differential cross section is fitted by the equation : E*D3(SIG)/D3(P) = CONST*(1-XL)**POWER*EXP(-SLOPE*PT**2).

Table 2

The differential cross section is fitted by the equation : E*D3(SIG)/D3(P) = CONST*(1-XL)**POWER*EXP(-SLOPE*PT**2).


STUDY OF THE UPSILON (9.46) MESON IN ELECTRON - POSITRON ANNIHILATIONS

Darden, C.W. ; Hasemann, H. ; Krolzig, A. ; et al.
Phys.Lett.B 80 (1979) 419-422, 1979.
Inspire Record 145168 DOI 10.17182/hepdata.27358

New data for the reaction e + e − →ϒ(9.46) have been obtained using the DASP detector at the DORIS storage ring. The electronic width Γ ee is (1.5±0.4) keV. The branching ratio for the decay into muon pairs is (2.5 ± 2.1)%. Energy spectra for inclusive production of hadrons are given.

2 data tables
Table 1

VISIBLE HADRONIC TOTAL CROSS SECTION.

Table 2

INVARIANT INCLUSIVE PRODUCTION CROSS SECTION E*D3(SIG)/DP**3 BOTH ON AND OFF THE UPSILON(9.46) RESONANCE. NO SIGNIFICANT DIFFERENCE IN EXPONENTIAL SLOPE AS A FUNCTION OF PARTICLE ENERGY E(P=3).


PRODUCTION OF PHOTONS ASSOCIATED WITH THE PSI BY 217-GEV/C PI- MESONS

Kirk, T.B.W. ; Raja, R. ; Goodman, M. ; et al.
Phys.Rev.Lett. 42 (1979) 619-622, 1979.
Inspire Record 145303 DOI 10.17182/hepdata.20780

Dimuon production is studied in 217-GeV/c π−-hydrogen and π−-beryllium collisions with a lead-glass array to detect photons associated with the ψ. The ψ−γ mass spectrum shows a 2.6-standard-deviation excess of events above background at ∼3.5 GeV. This excess, if attributed to the decay χ(∼3.5)→ψγ, implies that 0.70±0.28 of the ψ's are produced via radiative decay of one of the χ states.

2 data tables
Table 1

E*D(SIG)/D(XL) is fitted by (1-X)**POWER.

Table 2

No description provided.