HEPData Search

The KS0KS0 system produced in the reaction π−p→nKS0KS0 at 6.0 and 7 0 GeV/c has been studied utilizing the ANL 1.5-m streamer-chamber facility. A 400 000-photograph exposure yielded 5096 unweighted nKS0KS0 events. The cross section for this reaction was determined to be 9.6 ± 1.3 μb at 6.0 GeV/c and 8.7 ± 1.1 μb at 7.0 GeV/c. The decay angular distributions were parametrized in terms of moments of the spherical harmonics. The 〈Y40〉 moment was fitted to interfering Breit-Wigner amplitudes for the f and f′ mesons. Using this fit, the branching ratio R=Γ(f→KK¯)Γ(f→all) was found to be (2.3 ± 0.8)%. An energy-independent production-amplitude analysis revealed an enhancement in the S-wave amplitude near 1300 MeV. The properties of the S-wave enhancement are discussed and compared with those observed in other recent experiments. Extrapolated cross sections for the reaction ππ→KS0KS0 are presented. We find a cross section considerably below the S-wave unitarity limit in the S* region.

1 data table match query

Table 1

FROM FIT TO D-WAVE (M=0) KS KS, CORRECTED FOR <K+ K-> AND <KL KL> DECAY MODES.

anti-p p Interactions at 2.32-GeV/c

Chen, C.K. ; Fields, T. ; Rhines, D.S. ; et al.

Phys.Rev.D 17 (1978) 42, 1978.

Inspire Record 5667 DOI 10.17182/hepdata.24405

A bubble-chamber experiment based on 304 000 events of p¯p interactions at 2.32 GeV/c is described. The film was automatically scanned and measured by the POLLY II system. Details of the data-analysis methods are given. We report results on cross sections for constrained final states, tests of C invariance, and inclusive pion and ρ0 multiplicity parameters for annihilation final states.

2 data tables match query

Table 1

Axis error includes +- 4/4 contribution.

Table 2

Axis error includes +- 4/4 contribution.

Backward Resonance Production in pi- p --> n pi+ pi- at 8-GeV/c

Eisenstein, Bob I. ; Elliott, J. ; Mollet, W. ; et al.

Phys.Rev.D 18 (1978) 1370-1381, 1978.

Inspire Record 136306 DOI 10.17182/hepdata.24374

We have studied backward meson and baryon production in π−p→nπ+π− at 8 GeV/c using a streamer chamber triggered by the detection of the interaction of the neutron in thick-plate optical spark chambers. Our data sample of 866 events is dominated by the quasi-two-body final states Δ−(1232)π+, nρ0, and nf0. We study the differential and total backward cross sections for these states and the decay angular distributions of the resonances. The results for the Δ− and ρ0 indicate that both nucleon and Δ exchange in the u channel are important in their production, while f0 production is, as expected, consistent with nucleon exchange.

5 data tables match query

Table 1

No description provided.

Table 2

BACKWARD DIP.

Table 3

No description provided.

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Polarization Parameter for Nucleon-Nucleon Elastic Scattering at 11.8-GeV/c

Kramer, S.L. ; Ayres, D.S. ; Cohen, Daniel H. ; et al.

Phys.Rev.D 17 (1978) 1709, 1978.

Inspire Record 122176 DOI 10.17182/hepdata.24427

Data are presented on the polarization parameter in pp and pn elastic scattering at 11.8 GeV/c for four-momentum transfers −t=0.15 to 0.9 GeV2. In contrast to lower energies where the pn polarization is positive, it is slightly negative at 11.8 GeV/c; averaging the data from −t=0.18 to 0.5 GeV2 we find P(pn)=(−0.9±0.5)%, to be compared with P(pp)=(5.6±0.8)%. These data, combined with our previous data at lower energies, show that the I=0 single-flip exchange amplitude has an anomalously rapid energy dependence.

1 data table match query

Table 1

No description provided.

Observation of the reaction pi- p ---> anti-p d from 4 to 6 gev/c

Pawlicki, A.J. ; Ayres, D.S. ; Diebold, R. ; et al.

Phys.Rev.Lett. 31 (1973) 665-667, 1973.

Inspire Record 83780 DOI 10.17182/hepdata.21336

Differential cross sections have been measured for the reaction π−p→p¯d. At 4 GeV/c the total cross section is 0.58 ± 0.08 μb with an angular distribution consistent with isotropy. At 5 GeV/c a pronounced forward dip occurs. In contradiction to simple baryon-exchange models, the cross section is found to be an order of magnitude smaller than that for the line-reversed reaction pp→π+d. Upper limits for π−d→p¯t were also found.

2 data tables match query

Table 1

No description provided.

Table 2

No description provided.

rivet Analysis
Measurement of the eta and eta' transition form factors at q2 = 112-GeV2.

The BaBar collaboration Aubert, Bernard ; Barate, R. ; Bona, M. ; et al.

Phys.Rev.D 74 (2006) 012002, 2006.

Inspire Record 716277 DOI 10.17182/hepdata.22085

We report a study of the processes e+e- -> eta gamma and e+e- -> etaprime gamma at a center-of-mass energy of 10.58 GeV, using a 232 fb^-1 data sample collected with the BABAR detector at the PEP-II collider at SLAC. We observe 20+6-5 eta gamma and 50+8-7 etaprime gamma events over small backgrounds, and measure the cross sections sigma(e+e- -> eta gamma) =4.5+1.2-1.1(stat)+-0.3(sys) fb and sigma(e+e- -> etaprime gamma)=5.4+-0.8(stat)+-0.3(sys) fb. The corresponding transition form factors at q^2 = 112 GeV^2 are q^2|F_eta(q^2)|=0.229+-0.030+-0.008 GeV, and q^2|F_etaprime(q^2)|=0.251+-0.019+-0.008 GeV, respectively.

3 data tables match query

Table 1

Measured cross sections.

Table 2

Undressed cross sections calculated by applying a 7.5 +- 0.2 PCT correction for vacuum polarization.

Table 3

Transition form factors at Q**2 = 112 GeV**2.

Experimental Study of the Reactions $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \gamma \gamma$ at 29-{GeV}

Derrick, M. ; Gan, K.K. ; Kooijman, P. ; et al.

Phys.Rev.D 34 (1986) 3286, 1986.

Inspire Record 18585 DOI 10.17182/hepdata.23442

This paper reports measurements of the differential cross sections for the reactions e+e−→e+e− (Bhabha scattering) and e+e−→γγ (γ-pair production). The reactions are studied at a center-of-mass energy of 29 GeV and in the polar-angular region ‖costheta‖<0.55. A direct cross-section comparison between these two reactions provides a sensitive test of the predictions of quantum electrodynamics (QED) to order α3. When the ratio of γ-pair to Bhabha experimental cross sections, integrated over ‖costheta‖<0.55, is divided by the same ratio predicted from α3 QED theory, the result is 1.007±0.009±0.008. The 95%-confidence limits on the QED-cutoff parameters are Λ+>154 GeV and Λ−>220 GeV for Bhabha scattering, and Λ+>59 GeV and Λ−>59 GeV for γ-pair production.

1 data table match query

Table 1

No description provided.

rivet Analysis
Hadron Production in $e^+ e^-$ Annihilation at $\sqrt{s}=29$-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.

Phys.Rev.D 35 (1987) 2639, 1987.

Inspire Record 215848 DOI 10.17182/hepdata.23381

Data from the High Resolution Spectrometer at the SLAC storage ring PEP have been used to study the inclusive production of baryons and mesons. Time-of-flight measurements are used to identify the charged hadrons. Neutral hadrons are identified from effective-mass peaks associated with their decay into two charged particles. Cross sections and other inclusive production characteristics are presented for π±, K±, and K0 (K¯0) mesons, and for the baryons (antibaryons) p (p¯) and Λ (Λ¯). The ratio of the inclusive cross section to the point cross section for the K0 and K¯0 mesons is R(K0,K¯0)=6.15±0.13±0.25, and for Λ and Λ¯, R(Λ,Λ¯)=0.846±0.036±0.085. The neutral-hadron differential cross sections are compared with the predictions of the Lund string model.

8 data tables match query

Table 1

Charged particle fractions. Errors contain systematic uncertainties.

Table 2

Charged particle invariant cross sections. Errors contain systematic uncertainties.

Table 3

Charged particle invariant cross sections. Errors contain systematic uncertainties.

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$\pi^- p$ Interactions at 360-GeV/c: Measurement of the Total and Elastic Cross-Sections and the Charged Particle Multiplicity Distribution

Firestone, A. ; Anderson, E.W. ; Chang, V. ; et al.

Phys.Rev.D 14 (1976) 2902, 1976.

Inspire Record 3926 DOI 10.17182/hepdata.24670

In a sample of 108 563 pictures taken with the Fermilab 30-inch hydrogen bubble chamber, exposed to a 360-GeV/c π− beam, we have observed 19 453 interactions in a selected fiducial region. The observed charged multiplicity distribution has been corrected for the effects of scan efficiency, errors in prong count, missed close-in vees, secondary interactions, and neutron stars and for Dalitz pairs. The two-prong events have been corrected for losses at low −t. The total cross section is measured to be 25.25 ± 0.35 mb, and the elastic cross section is 3.61 ± 0.11 mb with an exponential slope of (8.82 ± 0.30) (GeV/c)−2. The average charged-particle multiplicity for inelastic events is 8.73 ± 0.04, and the second moment f2 is measured to be 9.83 ± 0.23.

1 data table match query

Table 2

FROM FIT, FORWARD D(SIG)/DT = 31.84 +- 0.68 MB/GEV**2, AND AGREES WITH OPTICAL POINT FROM MEASURED TOTAL CROSS SECTIONS.

Date

Collaboration

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Phrases

Reactions

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CM Energies (GeV)

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Measurement of the spin-density matrix elements in exclusive electroproduction of rho0 mesons at HERA.

Study of the Reaction $\pi^- p \to N K^0_S K^0_S$ at 6.0-{GeV}/$c$ and 7.0-{GeV}/$c$

anti-p p Interactions at 2.32-GeV/c

Backward Resonance Production in pi- p --> n pi+ pi- at 8-GeV/c

Polarization Parameter for Nucleon-Nucleon Elastic Scattering at 11.8-GeV/c

Observation of the reaction pi- p ---> anti-p d from 4 to 6 gev/c

rivet Analysis
Measurement of the eta and eta' transition form factors at q2 = 112-GeV2.

Experimental Study of the Reactions $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \gamma \gamma$ at 29-{GeV}

rivet Analysis
Hadron Production in $e^+ e^-$ Annihilation at $\sqrt{s}=29$-{GeV}

$\pi^- p$ Interactions at 360-GeV/c: Measurement of the Total and Elastic Cross-Sections and the Charged Particle Multiplicity Distribution