Becker, U.
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TWO PARTICLE INCLUSIVE AND SEMIINCLUSIVE RAPIDITY DISTRIBUTIONS OF pi+- MESONS IN K- p INTERACTIONS AT 32-GeV/c

The USSR-CERN collaboration Bumazhnov, V.A. ; Babintsev, V.V. ; Bogolyubsky, M.Yu. ; et al.
Sov.J.Nucl.Phys. 40 (1984) 96, 1984.
Inspire Record 190549 DOI 10.17182/hepdata.10678

None

83 data tables
Table 1

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High $p_T$ Direct Photon Production at 11-degrees in $p p$ Collisions at $\sqrt{s}=63$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 123 (1983) 367-372, 1983.
Inspire Record 188929 DOI 10.17182/hepdata.30744

The production of direct photons has been measured relative to π 0 's in the rapidity range 2.00 < y < 2.75 in pp collisions at s = 63 GeV at the CERN Intersecting Storage Rings. The γ/π 0 ratio increases from ⪅2% at p T = 1.5 GeV/ c to ∼8% at p T = 4.25 GeV/ c , similar to the value observed near 90°. The results indicate no strong enhancement of single-photon production due to quark bremsstrahlung in this kinematic region.

1 data table
Table 1

No description provided.


Production of $\pi^0$ and Eta0 at 11-degrees in $p p$ Collisions at $\sqrt{s}=63$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Z.Phys.C 18 (1983) 5, 1983.
Inspire Record 188928 DOI 10.17182/hepdata.16326

The inclusive π0 production cross-section and the η/π0 ratio have been measured inpp collisions at\(\sqrt s= 63 GeV\) at the CERN Intersecting Storage Rings in the rapidity range 2.00<y<2.75. The π0 cross-section exhibits a strongy-dependence and falls more steeply as a function ofpT, compared with the cross-section measured aty∼0. We find a value of 0.46±0.07 for the η/π0 ratio with no significantpT dependence over the range 2.0<pT<4.0 GeV/c.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Experimental Study of the Hadronic Photon Structure Function

The CELLO collaboration Behrend, H.J. ; Fenner, H. ; Gumpel, U. ; et al.
Phys.Lett.B 126 (1983) 391-397, 1983.
Inspire Record 198110 DOI 10.17182/hepdata.30720

We have measured at PETRA the process e γ → e + hadrons at an average Q 2 value of 9 GeV 2 / c 2 . The total number of observed events attributed to this process is 215. Our data are compared to calculations based on the estimation of the photon structure function F 2 in the quark parton model and in QCD.

1 data table
Table 1

No description provided.


Production of $\pi^0$ mesons in muon - hydrogen interactions at 200-GeV

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Z.Phys.C 18 (1983) 189, 1983.
Inspire Record 189283 DOI 10.17182/hepdata.16369

Thez andpT2 distributions of π0 mesons produced by the interaction of 200 GeV muons on hydrogen are presented. Comparisons are made with other π0 and charged hadron data and with the predictions of perturbative QCD. The data show a rise of 〈pT2〉 withW2 which is consistent with QCD, and withz2 which requires a contribution from a primordialkT. The fraction of total energy which appears as π0 mesons is 0.27±0.05.

1 data table
Table 1

No description provided.


A Model Independent Second Order Determination of the Strong Coupling Constant $\alpha^- s$

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 50 (1983) 2051, 1983.
Inspire Record 189724 DOI 10.17182/hepdata.3086

With use of the MARK-J detector at s=34.7 GeV 21 000 e+e−→hadron events have been collected. By measurement of the asymmetry in angular energy correlations the strong coupling constant αs=0.13±0.01 (statistical)±0.02 (systematic) is determined, in complete second order, and independent of the fragmentation models and QCD cutoff values used.

2 data tables
Table 1

DATA REQUESTED FROM THE AUTHORS.

Table 2

No description provided.


Proton - Anti-proton Annihilations at Rest Into $\pi^0 \omega$, $\pi^0 \eta$, $\pi^0 \gamma$, $\pi^0 \pi^0$, and $\pi^0 \eta^\prime$

Backenstoss, G. ; Hasinoff, M. ; Pavlopoulos, P. ; et al.
Nucl.Phys.B 228 (1983) 424-438, 1983.
Inspire Record 189897 DOI 10.17182/hepdata.33919

Proton-antiproton annihilations at rest in liquid hydrogen were investigated through the inclusive γ spectrum, related to the annihilation. The high-energy part of the spectrum was used to deduce branching ratios for the so far unobserved annihilation channels: R( p p →π 0 ω) = (2.38 ± 0.65)% , R( p p → π 0 η) = (0.82 ± 0.10% , R p p →π 0γ) = (0.015 ± 0.007)% , and R( p p → π 0 π 0 = (0.06 ± 0.04)% . An upper limit for the π 0 η ′ channel was deduced to be R( p p → π 0 η ′ ) < 1.1% .

1 data table
Table 1

RESULTS ALSO INCLUDE AN UNKNOWN PARTICLE X WHOSE BRANCHING RATIO IS 1.19 +- 0.25 (DSYS = 0.44) PCT.


The Dominance of Jets at Large Transverse Energy in a Full Azimuth Hadron Calorimeter at {ISR} Energies

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 128 (1983) 354-360, 1983.
Inspire Record 190652 DOI 10.17182/hepdata.30701

Events with a large transverse energy in a calorimeter with full azimuthal coverage and | y | < 0.9 have been investigated in pp collisions at √ s = 30, 45, and 63 GeV. A striking change in the event structure, corresponding to a clear emergence of high- p T jets, is observed at √ s = 63 and 45 GeV in the region between 25 and 35 GeV in transverse energy. At √ s = 30 GeV, the data extend to E T ∼ 20 GeV, but no such change in the event structure is observed.

3 data tables
Table 1

No description provided.

Table 2

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Experimental Study of Inclusive Muon Spectra at PETRA

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 51 (1983) 443, 1983.
Inspire Record 13422 DOI 10.17182/hepdata.20492

The results of a high-statistics study of inclusive muon spectra at PETRA are reported. Improved mass limits have been obtained for heavy quarks, heavy leptons, and charged Higgs particles. It is shown that the fragmentation properties of b quarks and c quarks are different, with the mean fragmentation variables 〈zb〉=0.75±0.03±0.06, 〈zc〉=0.46±0.02±0.05 and the average semileptonic branching ratio for the B and C hadrons R(B)=(10.5±1.5±1.3)%, R(C)=(11.5±1.0±1.7)%.

5 data tables
Table 1

No description provided.

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Measurement of the Processes $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \gamma \gamma$ at {PETRA}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Z.Phys.C 19 (1983) 197, 1983.
Inspire Record 191231 DOI 10.17182/hepdata.45206

Cross sections for the reactionse+e−→e+e− (Bhabha scattering) ande+e−→γγ are measured for center-of-mass (c.m.) energies\(\sqrt s \) between 12.0 and 34.6 GeV. The results agree with the predictions of Quantum Electrodynamics (QED) and the cut-off parameters are determined. From Bhabha scattering at the highest energy,\(\left\langle {\sqrt s } \right\rangle= 34.6 GeV\), the 1 δ limits 0.12<sin2 ϑw<0.38 are obtained for the weak mixing angle. The higher order (α3) QED processese+e−→e+e−γ ande+e−→γγγ are also studied and are found to agree with the α3 QED predictions. A search for excited electrons is carried out by investigating the (e±γ) invariant mass distribution in the reactione+e−→e+e−γ.

3 data tables
Table 1

Total cross sections.

Table 2

Angular distribution.

Table 3

Angular distribution.