Kawai, H.
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Observation of the p wave singlet state of charmonium

Armstrong, T.A. ; Bettoni, D. ; Bharadwaj, V. ; et al.
Phys.Rev.Lett. 69 (1992) 2337-2340, 1992.
Inspire Record 338054 DOI 10.17182/hepdata.42562

We have performed a search for the 1P1 state of charmonium resonantly formed in p¯p annihilations, close to the center of gravity of the 3PJ states. We report results from the study of the J/ψ+π0 and J/ψ+2π final states. We have observed a statistically significant enhancement in the p¯+p→J/ψ+π0 cross section at √s ≃3526.2 MeV. This enhancement has the characteristics of a narrow resonance of mass, total width, and production cross section consistent with what is expected for the 1P1 state. In our search we have found no candidates for the reactions p¯+p→J/ψ+π0+π0 and p¯+p→J/ψ+π++π−.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Inclusive charged hadron and K0 production in two photon interactions

Cords, D. ; Boyer, J. ; Butler, F. ; et al.
Phys.Lett.B 302 (1993) 341-344, 1993.
Inspire Record 340849 DOI 10.17182/hepdata.28958

The inclusive transverse momentum distributions of charged hadrons and K 0 's produced in tagged photon-photon collisions, are measured and compared to model calculations up to a p T of 5 GeV/ c . The relative abundance of K 0 's favor the inclusion of charm.

1 data table
Table 1

Data read from graph.


Determination of the number of light neutrino species

The L3 collaboration Adriani, O. ; Aguilar-Benitez, M. ; Ahlen, S. ; et al.
Phys.Lett.B 292 (1992) 463-471, 1992.
Inspire Record 339090 DOI 10.17182/hepdata.29030

We have measured the cross-section of the production of single photon events in e + e − collisions near the Z 0 resonance. For an integrated luminosity of 9.6 pb −1 , we have observed 202 single photon candidates with energy between 0.9 and 3.5 GeV in the polar angular region between 45° and 135°. Assuming that the only stable weakly interacting particles are light neutrinos with standard model couplings, we determine the number of light neutrino species to be N v = 3.14 ± 0.24 (stat.)±0.12 (syst.). This corresponds to an invisible Z 0 width of Γ inv = 524 ± 40 ± 20 MeV.

1 data table
Table 1

Corrected cross section.


Measurements of R(d) - R(p) and R(Ca) - R(C) in deep inelastic muon scattering

The New Muon collaboration Amaudruz, P. ; Arneodo, M. ; Arvidson, A. ; et al.
Phys.Lett.B 294 (1992) 120-126, 1992.
Inspire Record 340582 DOI 10.17182/hepdata.29038

Results are presented on the difference in R , the ratio of longitudinally to transversely polarised virtual photon absorption cross sections, for the deuteron and the proton. They are obtained by comparing the ratio of cross sections for the deep inelastic scattering of muons from deuterium and hydrogen targets at 90 and 280 GeV incident energy. The results cover the range x =0.01–0.30, at an average Q 2 of 9 GeV 2 . The measured difference R d - R p shows no significant x dependence and is compatible with zero, as well as with expectations from perturbative QCD. We use the same method to obtain the difference R Ca - R C from cross section ratios measured on carbon and calcium targets at 90 and 200 GeV incident energy.

4 data tables
Table 1

No description provided.

Table 2

Average overall x values.

Table 3

No description provided.

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Inclusive J / psi, psi (2S) and b quark production in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Anway, Carol E. ; et al.
Phys.Rev.Lett. 69 (1992) 3704-3708, 1992.
Inspire Record 340126 DOI 10.17182/hepdata.19780

Inclusive J/ψ and ψ(2S) production has been studied in p¯p collisions at √s =1.8 TeV using 2.6±0.2 pb−1 of data taken with the Collider Detector at Fermilab. The products of production cross section times branching fraction were measured as functions of PT for J/ψ→μ+μ− and ψ(2S)→μ+μ−. In the kinematic range PT>6 GeV/c and ‖η‖≤0.5 we get σ(p¯p→J/ψ X)B(J/ψ→μ+μ−) =6.88±0.23(stat)−1.08+0.93(syst) nb, and σ(p¯p→ψ(2S)X)B(ψ(2S)→μ+μ−) =0.232±0.051(stat)−0.032+0.029(syst)nb. From these values we calculate the inclusive b-quark production cross section.

6 data tables
Table 1

Cross section times the branching ratio into mu+ mu- pairs.

Table 2

Cross section times the branching ratio into mu+ mu- pairs.

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Feynman-x and Transverse Momentum Dependence on $D^{\pm}$ and $D^0$, $\bar{D}^0$ Production in 250 GeV $\pi^-$ Nucleon Interactions

The Fermilab E769 collaboration Alves, G.A. ; Amato, S. ; Anjos, J.C. ; et al.
Phys.Rev.Lett. 69 (1992) 3147-3150, 1992.
Inspire Record 338063 DOI 10.17182/hepdata.19804

We measure the differential cross section with respect to Feynman-x (xF) and transverse momentum (PT) for charm meson production using targets of Be, Al, Cu, and W. In the range 0.1

4 data tables
Table 1

No description provided.

Table 2

Results of fit to DSIG/DXL distribution of the form (1-XL)**POWER in the XL range 0.1 to 0.7. Statistical errors only. Systematic errors are small in comparison.

Table 3

Results of fit to DSIG/DPT**2 distribution of the form exp(-POWER*PT**2) in the PT**2 range 0.0 to 4.0 GeV**2.

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Production of f2 (1270) and f0 (975) mesons by photons and hadrons of energy 65-GeV - 175-GeV

The Omega Photon collaboration Apsimon, R.J. ; Atkinson, M. ; Baake, M. ; et al.
Z.Phys.C 56 (1992) 185-192, 1992.
Inspire Record 339969 DOI 10.17182/hepdata.16122

Measurements are reported of inclusivef2(1270) andf0(975) production in γp, π±p andK±p collisions at photon beam energies of 65 to 175 GeV and hadron beam energies of 80 and 140 GeV. Thef2 andf0 mesons were found at masses of 1.250 GeV and 0.961 GeV respectively. Inclusivef2 production at lowxF was found to have a similarpT dependence for each beam type, whereas an additional pion-exchange contribution was found for production by pions at highxF. Cross sections are compared with those for ρ0 production and give no indication of a non-q\(\bar q\) component in eitherf-meson state.

26 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Muoproduction of J / psi and the gluon distribution of the nucleon

The European Muon collaboration Ashman, J. ; Badelek, B. ; Baum, G. ; et al.
Z.Phys.C 56 (1992) 21-28, 1991.
Inspire Record 336767 DOI 10.17182/hepdata.14559

Measurements are presented of the inclusive distributions of theJ/Ψ meson produced by muons of energy 200 GeV from an ammonia target. The gluon distribution of the nucleon has been derived from the data in the range 0.04

7 data tables
Table 1

Data are normalized to total cross section of 36 nb (not corrected for coherence).

Table 2

Data are normalized to total cross section of 36 nb (not corrected for coherence).

Table 3

Data are normalized to total cross section of 36 nb (not corrected for coherence).

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A Measurement of the ratio of the nucleon structure function in copper and deuterium

The European Muon collaboration Ashman, J. ; Badelek, B. ; Baum, G. ; et al.
Z.Phys.C 57 (1993) 211-218, 1993.
Inspire Record 341575 DOI 10.17182/hepdata.14499

Results are presented on the ratios of the nucleon structure function in copper to deuterium from two separate experiments. The data confirm that the nucleon structure function,F2, is different for bound nucleons than for the quasi-free ones in the deuteron. The redistribution in the fraction of the nucleon's momentum carried by quarks is investigated and it is found that the data are compatible with no integral loss of quark momenta due to nuclear effects.

3 data tables
Table 1

Results from the 'chariot' experiment.

Table 2

Results from the 'addendum' experiment.

Table 3

Merged 'chariot' and 'addendum' ratio.. Errors are combined statistics and systematics.


Measurement of the proton electromagnetic form-factors in the timelike region at 8.9-GeV**2 - 13-GeV**2

The E760 collaboration Armstrong, T.A. ; Bettoni, D. ; Bharadwaj, V. ; et al.
Phys.Rev.Lett. 70 (1993) 1212-1215, 1993.
Inspire Record 340584 DOI 10.17182/hepdata.19781

Cross sections for the reaction pp¯→e+e− have been measured at s=8.9,12.4, and 13.0 GeV2. The cross sections have been analyzed to obtain the proton electromagnetic form factors in the timelike region. We find that GM(q2)∝q−4αs2(q2) for q2≥5 (GeV/c)2.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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