Date

First Observation of $\gamma \gamma \to K^*0 \bar{K}^*$0

The ARGUS collaboration Albrecht, H. ; Andam, A.A. ; Binder, U. ; et al.
Phys.Lett.B 198 (1987) 255-260, 1987.
Inspire Record 248680 DOI 10.17182/hepdata.30080

The final state K + K − π + π − has been studied in γγ interactions using the ARGUS detector at the e + e − storage ring DORIS II at DESY. Production of the vector meson pair K ∗0 (892) K ∗0 (892) is observed for the first time. The cross section for K + K − π + π − , K ∗0 K − π + +c.c. and K ∗0 K ∗0 are all found to be of the order of a few nb. In the W γγ range accessible, a mean upper limit of 0.5 nb at 95% CL is derived for φϱ 0 production.

6 data tables

TOPOLOGICAL CROSS SECTION.

(K*0 K*BAR0) cross section.

(K*0 K- PI+ + CC) CROSS SECTION WITH (K*0 K*BAR0) REMOVED.

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Search for a Narrow Resonance in Anti-proton - Proton Annihilation Cross-sections in the Beam Momentum Range Between 400-{MeV}/$c$ and 600-{MeV}/$c$

Brückner, W. ; Cujec, B. ; Döbbeling, H. ; et al.
Phys.Lett.B 197 (1987) 463, 1987.
Inspire Record 249661 DOI 10.17182/hepdata.30103

A measurement of the p p annihilation cross section in the beam momentum region between 400 and 600 MeV/ c has been performed with a mass resolution of 1 MeV/ c 2 and statistical precision generally better than 1%. No evidence for the X(1935) resonance is found. The upper limit at the 90% confidence level is 5 mb MeV/ c 2 for a width of 2 MeV/ c 2 .

1 data table

Statistical errors only.


Determination of $\alpha^- s$ From a Measurement of the Direct Photon Spectrum in $\Upsilon$ (1s) Decays

The ARGUS collaboration Albrecht, H. ; Andam, A.A. ; Binder, U. ; et al.
Phys.Lett.B 199 (1987) 291-296, 1987.
Inspire Record 248655 DOI 10.17182/hepdata.30061

Using the ARGUS detector at the DORIS II e + e − storage ring we have measured direct photons from the decay ???(1 S )→ γgg . The ratio R γ = Γ (???(1S)→ γgg )/ Γ (???(1S)→ ggg )=(3.00±0.13±0.18)% has been determined, from which we deduce values of the strong coupling constant α s =0.225±0.011±0.019 and the QCD scale parameter Λ MS =115±17±28 MeV defined in the modified minimal-subtraction scheme. The shape of the measured spectrum clearly rules out the predictions of the lowest order QCD calculations.

1 data table

No description provided.


The Real Part of the Proton - anti-Proton Elastic Scattering Amplitude at the Center-Of-Mass Energy of 546-GeV

The UA4 collaboration Bernard, Denis ; Bozzo, M. ; Braccini, P.L. ; et al.
Phys.Lett.B 198 (1987) 583, 1987.
Inspire Record 249671 DOI 10.17182/hepdata.30077

Proton-antiproton elastic scattering was measured at the CERN SPS Collider at the centr-of-mass energy s =546 GeV in the Coulomb interference region. The data provide information on the phase of the hadronic amplitude in the forward direction. The conventional analysis gives for the ratio ϱ of the real to the imaginary part of the hadronic amplitude the result ϱ =0.24±0.04.

2 data tables

Axis error includes +- 0.025/0.025 contribution (Normalisation was fixed using a previous UA4 measurement of the total cross section: sig(name=tot)*(1 + alpha**2)).

Best estimate of alpha(rho).


Experimental Test of the {PCAC} Hypothesis in Charged Current Neutrino and Anti-neutrino Interactions on Protons

The Birmingham-CERN-London-Munich-Oxford-London & WA21 collaborations Jones, G.T. ; Jones, R.W.L. ; Kennedy, B.W. ; et al.
Z.Phys.C 37 (1987) 25-38, 1987.
Inspire Record 248866 DOI 10.17182/hepdata.15696

Data obtained with the bubble chamber BEBC at CERN are used for the first significant test of Adler's prediction for the neutrino and antineutrino-proton scattering cross sections at vanishing four-momentum transfer squaredQ2. An Extended Vector Meson Dominance Model (EVDM) is applied to extrapolate Adler's prediction to experimentally accessible values ofQ2. The data show good agreement with Adler's prediction forQ2→0 thus confirming the PCAC hypothesis in the kinematical region of high leptonic energy transfer ν>2 GeV. The good agreement of the data with the theoretical predictions also at higherQ2, where the EVDM terms are dominant, also supports this model. However, an EVDM calculation without PCAC is clearly ruled out by the data.

4 data tables

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High Transverse Momentum $\pi^0$ Production by $\pi^-$ and $\pi^+$ on Protons at 280-{GeV}/$c$

The WA70 collaboration Bonesini, M. ; Bonvin, E. ; Booth, P.S. L. ; et al.
Z.Phys.C 37 (1987) 39-50, 1987.
Inspire Record 250754 DOI 10.17182/hepdata.15679

The inclusive cross sections for π0 production by π− and π+ on protons have been measured with a beam momentum of 280 GeV/c using a fine grained electromagnetic calorimeter and the CERN Omega spectrometer. The transverse momentum and FeynmanxF ranges covered are 4.0<pT<7.0 GeV/c and −0.45<xF<0.6 respectively. The data are compared with leading order QCD calculations.

2 data tables

No description provided.

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The Transverse Energy Distribution in $^{16}$O - Nucleus Collisions at 60-{GeV} and 200-{GeV} Per Nucleon

The HELIOS collaboration Akesson, T. ; Almehed, S. ; Angelis, A.L.S. ; et al.
Z.Phys.C 38 (1988) 383, 1988.
Inspire Record 250767 DOI 10.17182/hepdata.15648

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6 data tables

No description provided.

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The Transverse Energy Distribution in Hadron - Lead Collisions

Åkesson, T. ; Choi, Y. ; Dam, P. ; et al.
Z.Phys.C 38 (1988) 397, 1988.
Inspire Record 250759 DOI 10.17182/hepdata.15655

The transverse energy cross-sectiondσ/dET has been measured in the pseudorapidity region 0.6<η<2.4 for hadron-lead collisions at 200 GeV/c incident hadron momentum. TheET distribution extends to 40 GeV, which is twice the kinematic limit forp-p collisions at the same incident beam momentum. The distribution ofET is found to shift towards low pseudorapidities with increasing total transverse energy.

1 data table

Statistical error only.


Energy Dependence of the Charge Asymmetry a ($T (\pi$), $\theta$) in $\pi d$ Elastic Scattering

Smith, G.R. ; Gill, D.R. ; Ottewell, D. ; et al.
Phys.Rev.C 38 (1988) 240-250, 1988.
Inspire Record 250814 DOI 10.17182/hepdata.26223

Angular distributions of charge asymmetry A(Tπ,θ), have been measured for πd elastic scattering. Data were obtained in the backward hemisphere for pion bombarding energies of 143, 180, 220, and 256 MeV. The results are compared with predictions employing different mass and width parameters for the delta isobars.

4 data tables

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