HEPData Search

Hadronic events obtained with the CELLO detector at PETRA were compared with first-order QCD predictions using two different models for the fragmentation of quarks and gluons, the Hoyer model and the Lund model. Both models are in reasonable agreement with the data, although they do not completely reproduce the details of many distributions. Several methods have been applied to determine the strong coupling constant α S . Although within one model the value of α S varies by 20% among the different methods, the values determined using the Lund model are 30% or more larger (depending on the method used) than the values determined with the Hoyer model. Our results using the Hoyer model are in agreement with previous results based on this approach.

3 data tables

Table 1

DATA CORRECTED WITH HOYER MODEL (ALPHA-S=0.15).

Table 2

DATA CORRECTED WITH LUND MODEL (ALPHA-S=0.25).

Table 3

No description provided.

Search for charmed particles with the heavy liquid bubble chamber BIBC

Badertscher, A. ; Hahn, B. ; Hugentobler, E. ; et al.

Phys.Lett.B 123 (1983) 471-476, 1983.

Inspire Record 179578 DOI 10.17182/hepdata.30743

In a search for short lived particles with a high resolution C 3 F 8 bubble chamber and a streamer chamber, 21 charmed meson candidates produced by 340 GeV cπ − have been identified. The cross section for associated charm production is (28±11) μb per nucleon assuming a linear A -dependence. The mean lifetimes of the D mesons in units of 10 −13 s are τ( D 0 , D ̄ 0 ) = 4.1 −1.3 +2.6 ± 0.5, τ( D ± ) = 6.3 −2.3 4.8 ± 1.5 .

1 data table

Table 1

LINEAR A DEPENDENCE ASSUMED FROM PROD. OF 33+-13 D-DBAR EVENTS.

Direct Evidence for the Emergence of Jets in Events Triggered on Large Transverse Energy 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 118 (1982) 185-192, 1982.

Inspire Record 179517 DOI 10.17182/hepdata.30854

We present data obtained from a 1.7 sr hadron calorimeter, triggered on transverse energy, in pp collisions at s =63 GeV at the CERN-ISR. From the change in the distribution of energy in the calorimeter, we extract the cross section for two-constituent hard scattering for p T between 6 and 14 GeV at y = 0. The decrease of this jet cross section over this p T range is consistent with exp (− bp T ), with b = (1.02 ± 0.09) GeV −1 . The slope and normalization of the cross section agree well with a QCD motivated Monte Carlo model. The ratio between jet and single particle cross sections [ dσ JET / dp T )/( dσ π 0 / dp T )]| y = 0 changes from about 200 at 6 GeV to about 1500 at 14 GeV.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Transverse Momentum Spectra for Charged Particles at the CERN Proton anti-Proton Collider

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.

Phys.Lett.B 118 (1982) 167-172, 1982.

Inspire Record 179520 DOI 10.17182/hepdata.30855

We have measured transverse momentum spectra up to 10 GeV/ c for charged particles produced centrally in proton-antiproton collisions at 540 GeV in the centre of mass at the CERN collider. Our results are compared with data at ISR energies and with the predictions of a QCD model. The charged particle spectrum shows a clear dependence on charged track multiplicity.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Observation of Very Large Transverse Momentum Jets at the CERN anti-p p Collider

The UA2 collaboration Banner, M. ; Bloch, P. ; Bonaudi, F. ; et al.

Phys.Lett.B 118 (1982) 203-210, 1982.

Inspire Record 180797 DOI 10.17182/hepdata.30853

The distribution of total tranverse energy ΣE T over the pseudorapidity interval −1 < η < 1 and an azimuthal range Δφ =300° has been measured in the UA2 experiment at the CERN p p collider ( s = 540 GeV ) using a highly segmented total absorption caloriter. In the events with very large ΣE T (ΣE T ⪆60 GeV ) most of the transverse energy is found to be contained in small angular regions as expected for high transverse momentum hadron jets. We discuss the properties of a sample of two-jet events with invariant two-jet masses up to 140 GeV c 2 and we measure the cross section for inclusive jet production in the range of jet transverse momenta between 15 and 60 GeV c .

5 data tables

Table 1

No description provided.

Table 2

HERE ET IS ACTUALLY THE ENERGY-DENSITY=ET/DELTA OMEGA.

Table 3

No description provided.

More…

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

Table 1

No description provided.

Table 2

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.

Multiplicity Distributions in $p \alpha$ and $\alpha \alpha$ Collisions in the {CERN} {ISR}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.

Phys.Lett.B 119 (1982) 464, 1982.

Inspire Record 179518 DOI 10.17182/hepdata.6665

Measurements of charged particle multiplicity distributions in the central rapidity region in p-p and p-α, and α-α collisions are reported. They are better fitted to the “wounded nucleon” than to the “gluon string” model. The average transverse momenta, for all three reactions, are identical (and almost independent of multiplicity) up to very high multiplicities.

2 data tables

Table 1

THE FIRST PP DATA IS AT 44 GEV, THE SECOND AT 63 GEV.

Table 2

No description provided.

Small Angle Elastic Scattering at the {CERN} Proton Anti-proton Collider

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.

Phys.Lett.B 121 (1983) 77-82, 1983.

Inspire Record 180683 DOI 10.17182/hepdata.66558

3roton-antiproton elastic scattering at cm energy 540 GeV has been studied in the t range 0.14 ⩽ − t ⩽ 0.26 GeV 2 . The data is well fitted by an exponential form exp( bt ) with b = 13.3 ± 1.5 GeV −2 .

2 data tables

Table 1

Elastic Differentiaol Cross Section (545 events). DATA REQUESTED 21 FEB 1983. Data read from plot in paper (29 JAN 2015).

Table 2

No description provided.

An Experimental Study of Large Angle Elastic Scattering of Charged Mesons and Anti-protons on Protons at 20-{GeV}/$c$ and 30-{GeV}/$c$

The Annecy(LAPP)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Baglin, C. ; Bock, R. ; Brobakken, K. ; et al.

Nucl.Phys.B 216 (1983) 1-39, 1983.

Inspire Record 180922 DOI 10.17182/hepdata.34020

A description is given of an experiment to study elastic scattering of π ± , K ± and p on protons at c.m. scattering angles from 45° to 100° at incident laboratory momenta 20 GeV/ c and 30 GeV/ c . The corresponding t range is from −6.2 (GeV/ c ) 2 to −28 (GeV/ c ) 2 . There are no previous observations for these reactions in this t range. High intensity and large geometrical acceptance were required in order to measure the low cross sections. The experiment used a double-arm spectrometer. MWPCs were used for reconstruction, and threshold and differential Čerenkov counters for identification. Scintillation counters, Čerenkov counters and a hadron calorimeter were used in the trigger. The trigger logic utilized specially designed matrices and a hard wired microprocessor. The π − p elastic scattering cross sections follow approximately the dimensional counting rule from 3.5 GeV/ c .and up to 30 GeV/ c . The cross sections decrease by seven orders of magnitude in this energy range. The data is compared to quark models. None of these models give a comprehensive description of the results. However, some modifications to these models improve their consistency with the data.

8 data tables

Table 1

EARLIER RESULTS GIVEN IN 'A'.

Table 2

No description provided.

Table 3

No description provided.

More…

Date

Collaboration

Subject_areas

Phrases

Reactions

Observables

CM Energies (GeV)

Authors Reset

CROSS-SECTIONS, AVERAGE MULTIPLICITIES AND ENERGY FRACTIONS OF NEUTRAL pi- AND K MESONS IN anti-p p ANNIHILATIONS AT 22.4-GeV/c

The Influence of Fragmentation Models on the Determination of the Strong Coupling Constant in $e^+ e^-$ Annihilation Into Hadrons

Search for charmed particles with the heavy liquid bubble chamber BIBC

Direct Evidence for the Emergence of Jets in Events Triggered on Large Transverse Energy in $p p$ Collisions at $\sqrt{s}=63$-{GeV}

Transverse Momentum Spectra for Charged Particles at the CERN Proton anti-Proton Collider

Observation of Very Large Transverse Momentum Jets at the CERN anti-p p Collider

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

Multiplicity Distributions in $p \alpha$ and $\alpha \alpha$ Collisions in the {CERN} {ISR}

Small Angle Elastic Scattering at the {CERN} Proton Anti-proton Collider

An Experimental Study of Large Angle Elastic Scattering of Charged Mesons and Anti-protons on Protons at 20-{GeV}/$c$ and 30-{GeV}/$c$