Date

Production of Charmed Particles in 250-GeV mu+ - Iron Interactions

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Nucl.Phys.B 213 (1983) 31-64, 1983.
Inspire Record 180921 DOI 10.17182/hepdata.46965

Dimuon and trimuon events produced by the interaction of 250 GeV muons in an iron target have been studied and are shown to originate predominantly from charm production. The data are used to measure the contribution of charm to the nucleon structure function F 2 . The cross sections for real photoproduction ( Q 2 =0) of charm in the current fragmentation region are derived as a function of photon energy and are found to be ∼0.6% of the total, hadronic photoproduction cross section in this energy range. The measured cross sections are found to be well represented by the photon-gluon fusion model. The charmed quark fragmentation function is obtained by using this model to fit the measured decay muon energy distribution and is found to be well represented by exp(1.6±1.6) Z . The data are used to study the momentum distribution of the gluons in the nucleon. An upper limit of 1.4% (90% confidence level) is set on the branching ratio D→ μν and a model-dependent upper limit on the branching ratio F→ μν is derived.

9 data tables

The charm contribution to the nucleon structure function from the dimuon data.

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STUDY OF PROTON DIFFRACTIVE EXCITATION PROCESSES IN REACTION K+ p ---> K+ p pi+ pi- AT 32-GeV/c

The Soviet-CERN collaboration Chliapnikov, P.V. ; Falaleev, V.P. ; Garuchava, Z.Sh. ; et al.
Sov.J.Nucl.Phys. 38 (1983) 235, 1983.
Inspire Record 183145 DOI 10.17182/hepdata.41204

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5 data tables

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Coupling Strengths of Weak Neutral Currents From Leptonic Final States at 22-{GeV} and 34-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Z.Phys.C 16 (1983) 301, 1983.
Inspire Record 180756 DOI 10.17182/hepdata.16385

Differential cross sections fore+e−→e+e−, τ+, τ- measured with the CELLO detector at\(\left\langle {\sqrt s } \right\rangle= 34.2GeV\) have been analyzed for electroweak contributions. Vector and axial vector coupling constants were obtained in a simultaneous fit to the three differential cross sections assuming a universal weak interaction for the charged leptons. The results,v2=−0.12±0.33 anda2=1.22±0.47, are in good agreement with predictions from the standardSU(2)×U(1) model for\(\sin ^2 \theta _w= 0.228\). Combining this result with neutrino-electron scattering data gives a unique axial vector dominated solution for the leptonic weak couplings. Assuming the validity of the standard model, a value of\(\sin ^2 \theta _w= 0.21_{ - 0.09}^{ + 0.14}\) is obtained for the electroweak mixing angle. Additional vector currents are not observed (C<0.031 is obtained at the 95% C.L.).

2 data tables

No description provided.

Combined MU and TAU asymmetry. See PL 114B(1982)282 (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+1234> RED = 1234 </a>) and ZP C14(1982)283 (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+1245> RED = 1245 </a>) for individual asymmetry measurements.


Angular Correlations in gamma Gamma ---> rho0 rho0 Near Threshold

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gather, K. ; et al.
Z.Phys.C 16 (1982) 13, 1982.
Inspire Record 180755 DOI 10.17182/hepdata.16415

We present an analysis ofρ0ρ0 production by two photons in theρ0ρ0 invariant mass range from 1.2 to 2.0 GeV. From a study of the angular correlations in the process γγ→ρ0ρ0→π−π+π− we exclude a dominant contribution fromJP=0− or 2− states. The data indicate sizeable contributions fromJP=0+ for four pion massesM4π<1.7 GeV and fromJP=2+ forM4π>1.7 GeV. The data are also well described by a model with isotropic production and uncorrelated isotropic decay of theρ0,s. The cross section stays high below the nominalρ0ρ0 threshold, i.e.M4π<1.5 GeV. The matrix element forρ0ρ0 production is found to decrease steeply with increasingM4π. Upper limits for the couplings of the ι(1440) and Θ(1640) to γγ andρ0ρ0 are given:Γ(ι→γγ)·B(ι→ρ0ρ0)<1.0 keV andΓ(Θ→γγ)

2 data tables

ASSUMING ISOTROPIC RHO0 RHO0 PRODUCTION AND ISOTROPIC RHO DECAY.

CROSS SECTIONS FOR DIFFERENT SPIN-PARITY CONTRIBUTIONS.



Observation of a $K^*$ Resonance at 2088-{MeV}

The Birmingham-CERN-Glasgow-Michigan State-Paris collaboration Baubillier, M. ; Bloodworth, I.J. ; Burns, A. ; et al.
Phys.Lett.B 118 (1982) 447, 1982.
Inspire Record 179090 DOI 10.17182/hepdata.30838

In a high statistics (180 events/μb) bubble chamber study of the reaction fx K − p → K 0 π − p at 8.25 GeV c , we observe a K 0 π − state at 2088±20 MeV with a width 170 +100 −50 MeV, produced with a cross section of 3.6±1.2 μ b. In addition we observe this state in the channels K ∗ (890)ππ , ϱ K π , ω K π with a combined cross section of 7.1±2.6 μ b, and possibly K ∗ (890)πππ .

2 data tables

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Measurement of R in $e^+ e^-$ Annihilation for $\sqrt{s}$ Between 7.4-{GeV} and 9.4-{GeV}

The LENA collaboration Niczyporuk, B. ; Jakubowski, Z. ; Nowak, G. ; et al.
Z.Phys.C 15 (1982) 299, 1982.
Inspire Record 179431 DOI 10.17182/hepdata.16412

The rationR=σ(e+e−→hadrons)/σ(e+e−→ µ+ µ−) was measured with the LENA detector at DORIS in a scan between 7.40 and 7.48 GeV and between 8.67 and 9.43 GeV center of mass energies. Corrected for QED radiative effects,R is found to be constant with an average value ofR=3.37 ±0.06stat±0.23syst. No narrow resonances withΓee(Γhad/Γtot)⊗0.30 keV (95% C.L.) and no steps have been observed. Based on this value ofR, revised values for υ(1S) resonance parameters are presented.

3 data tables

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NUMERICAL VALUES GIVEN IN APPENDIX IN PREPRINT. STATISTICAL ERRORS ONLY.


DIRECT OBSERVATION OF THE DECAY h0 (2040) ---> anti-p p

Lamsa, J.W. ; Firestone, A. ; Anderson, E.W. ; et al.
Phys.Rev.D 26 (1982) 1769, 1982.
Inspire Record 12398 DOI 10.17182/hepdata.23947

We have observed the decay h0(2040)→p¯p in the reaction π+n→p¯pp at 10 GeV/c detected in the large-aperture solenoid spectrometer at SLAC. We have measured the product of the cross section and branching ratio, σ(π+n→h0(2040)p)B(h0(2040)→p¯p), to be 0.84±0.17 μb. The moments of the angular distribution are consistent with the quantum numbers of the h0 meson being JPC=4++ and IG=0+.

1 data table

Axis error includes +- 0.0/0.0 contribution (?/////BREIT-WIGNER PLUS POLYNOMIAL BACKGROUND FITTED TO P AP MASS DISTRIBUTION/REQUIRED THE MOMENTUM OF ONE P AND ONE AP TO BE >3 GEV, AND ONLY USED FOR THE FASTER P IN THE P AP MASS DISTRIBUTION).


Observation of Baryons With High Transverse Momenta in $p$, $d$, He and C Nuclear Interactions With Tantalum Nuclei at 4.2-{GeV}/$c$

Akhababian, N. ; Baatar, Ts. ; Baldin, A.M. ; et al.
Sov.J.Nucl.Phys. 37 (1983) 559, 1983.
Inspire Record 180913 DOI 10.17182/hepdata.9923

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10 data tables

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Measurement of the Proton - Anti-proton Elastic and Total Cross-section at a Center-of-mass Energy of 540-{GeV}

The UA4 collaboration Battiston, R. ; Bozzo, M. ; Braccini, P.L. ; et al.
Phys.Lett.B 117 (1982) 126-130, 1982.
Inspire Record 178898 DOI 10.17182/hepdata.30870

First results on the measurement of the elastic and total cross section at the CERN pp̄ Collider are presented. Combining the measurement of elastic scattering at low momentum transfer with the rate of inelastic interactions, a value of the total cross section of 66 mb with a 10% statistical error was obtained.

1 data table

STATISTICAL ERROR ONLY.