Probing hard color singlet exchange in p anti-p collisions at S**(1/2) = 630-GeV and 1800-GeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Lett.B 440 (1998) 189-202, 1998.
Inspire Record 476389 DOI 10.17182/hepdata.42131

We present results on dijet production via hard color-singlet exchange in proton-antiproton collisions at root-s = 630 GeV and 1800 GeV using the DZero detector. The fraction of dijet events produced via color-singlet exchange is measured as a function of jet transverse energy, separation in pseudorapidity between the two highest transverse energy jets, and proton-antiproton center-of-mass energy. The results are consistent with a color-singlet fraction that increases with an increasing fraction of quark-initiated processes and inconsistent with two-gluon models for the hard color-singlet.

2 data tables

Colour-singlet fraction at 1.8 TeV.

Ratio of colour-singlet fractions between 630 and 1800 GeV.


Measurement of event shape and inclusive distributions at s**(1/2) = 130-GeV and 136-GeV.

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Z.Phys.C 73 (1997) 229-242, 1997.
Inspire Record 424629 DOI 10.17182/hepdata.47715

Inclusive charged particle and event shape distributions are measured using 321 hadronic events collected with the DELPHI experiment at LEP at effective centre of mass energies of 130 to 136 GeV. These distributions are presented and compared to data at lower energies, in particular to the precise Z data. Fragmentation models describe the observed changes of the distributions well. The energy dependence of the means of the event shape variables can also be described using second order QCD plus power terms. A method independent of fragmentation model corrections is used to determine αs from the energy dependence of the mean thrust and heavy jet mass. It is measured to be: $$←pha _s(133 {⤪ GeV})={0.116}pm {0.007}_{exp-0.004theo}^{+0.005}$$ from the high energy data.

26 data tables

mean values for event shape variables.

Integral of event shape distribution over the specified interval.

Integral of event shape distribution over the specified interval.

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Study of charged current e p interactions at Q**2 > 200-Gev**2 with the ZEUS detector at HERA

The ZEUS collaboration Derrick, M. ; Krakauer, D. ; Magill, S. ; et al.
Z.Phys.C 72 (1996) 47-64, 1996.
Inspire Record 420053 DOI 10.17182/hepdata.44714

Deep inelastic charged--current reactions have been studied in $e~+p$ and $e~-p$ collisions at a center of mass energy of about $300\,\gev$ in the kinematic region $Q~2\greater200\,\gev~2$ and $x\greater0.006$ using the ZEUS detector at HERA. The integrated cross sections for $Q~2\greater200\,\gev~2$ are found to be $\sigep=30.3\,{}~{+5.5}_{\mns4.2}\,{}~{+1.6}_{\mns2.6}\,{\rm pb}$ and $\sigem=54.7\,{}~{+15.9}_{\mns\chax 9.8}\,{}~{+2.8}_{\mns3.4}\,{\rm pb}$. Differential cross sections have been measured as functions of the variables $x$, $y$ and $Q~2$. From the measured differential cross sections $d\sigma/dQ~2$, the $W$ boson mass is determined to be $M_W=79\,{}~{+8} _{-7}{}~{+4}_{-4}\,\gev$. Measured jet rates and transverse energy profiles agree with model predictions. A search for charged--current interactions with a large rapidity gap yielded one candidate event, corresponding to a cross section of $\sigep(Q~2\greater200\,\gev~2;\eta_{\rm max}<2.5)=0.8\,{}_{-0.7}~ {+1.8}\,\pm0.1\,{\rm pb}$.

11 data tables

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Topological characteristics of the charge exchange reaction H-3 ---> He-3 on neon and magnesium nuclei at 9-GeV/c

Avramenko, S.A. ; Aksinenko, V.D. ; Anikina, M.Kh. ; et al.
JINR-P1-91-240, 1991.
Inspire Record 319449 DOI 10.17182/hepdata.38713

None

2 data tables

No description provided.

No description provided.


Charged particle multiplicity distributions in Z0 hadronic decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.
Z.Phys.C 50 (1991) 185-194, 1991.
Inspire Record 301657 DOI 10.17182/hepdata.15028

This paper presents an analysis of the multiplicity distributions of charged particles produced inZ0 hadronic decays in the DELPHI detector. It is based on a sample of 25364 events. The average multiplicity is =20.71±0.04(stat)±0.77(syst) and the dispersionD=6.28±0.03(stat)±0.43(syst). The data are compared with the results at lower energies and with the predictions of phenomenological models. The Lund parton shower model describes the data reasonably well. The multiplicity distributions show approximate KNO-scaling. They also show positive forward-backward correlations that are strongest in the central region of rapidity and for particles of opposite charge.

5 data tables

Charged particle multiplicity distribution for the raw data in full phase space.

Charged particle multiplicity distribution for full phase space. Errors include systematics. A 2 pct correction for excess electrons from photon conversions is not included. The first two points, at N=2 and 4, were not measured but taken from the Lund PS model.

Charged particle multiplicity distribution for single hemisphere. Errors include systematics. A 2 pct correction for excess electrons from photon conversions is not included.

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Search for a Possible Exotic State C (1480) at the Vepp-2m Storage Ring

Aulchenko, V.M. ; Golubev, V.B. ; Dolinsky, S.I. ; et al.
JETP Lett. 45 (1987) 145-147, 1987.
Inspire Record 253283 DOI 10.17182/hepdata.2401

None

3 data tables

No description provided.

No description provided.

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E+ E- PAIR PRODUCTION BY A SYNCHROTRON RADIATION PHOTON ON A COUNTER BEAM ELECTRON. (IN RUSSIAN)

Blinov, A.E. ; Bondar, A.F. ; Bukin, A.D. ; et al.
Yad.Fiz. 45 (1987) 1008-1014, 1987.
Inspire Record 256613 DOI 10.17182/hepdata.17424

None

3 data tables

Axis error includes +- 2/2 contribution (Error in counter efficiency determination).

Electron momentum distribution.

Electron-positron pairs mass distribution.


OBSERVATION OF A NARROW MESON WITH A MASS OF 1750-MeV DECAYING INTO eta eta PAIR

The Serpukhov-Brussels-Annecy(LAPP) collaboration Alde, D. ; Binon, F.G. ; Bricman, C. ; et al.
IFVE-86-155, 1986.
Inspire Record 234608 DOI 10.17182/hepdata.10523

None

3 data tables

No description provided.

No description provided.

No description provided.


Study of a Possible Exotic $\phi \pi^0$ State With a Mass of About 1.5-{GeV}/$c^2$

Bityukov, S.I. ; Dzhelyadin, R.I. ; Dorofeev, V.A. ; et al.
Phys.Lett.B 188 (1987) 383, 1987.
Inspire Record 233160 DOI 10.17182/hepdata.10556

New data have been obtained on a resonance in the ϕπ 0 system, the C meson, which is formed in the π − p → ϕπ 0 n charge-exchange reaction. The experiment has been performed at the Serpukhov 70 GeV accelerator. The mass and the width of the resonance are measured to be M =1480±40 MeV , Γ =130±60 MeV . The production cross section is determined at a π − momentum of 32.5 GeV / c : σ ( π − p → Cn )· BR ( C → ϕπ 0 )=40±15 nb . The C(1480) meson has an isospin I =1 and spin-parity J PC =1 − − . It is strongly coupled to the ϕπ 0 channel and is considered as a possible exotic meson.

3 data tables

No description provided.

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THE ACCEPTANCE CORRECTED DISTRIBUTION.


STUDY OF CUMULATIVE PROTON PRODUCTION IN NEUTRINO - NUCLEAR INTERACTIONS

Ammosov, V.V. ; Baranov, D.S. ; Ivanilov, A.A. ; et al.
IFVE-85-109, 1985.
Inspire Record 218430 DOI 10.17182/hepdata.40895

None

11 data tables

No description provided.

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