A New determination of alpha(s) using direct photon production cross-sections in p p and anti-p p collisions at S**(1/2) = 24.3-GeV

The UA6 collaboration Werlen, M. ; Ballocchi, G. ; Breedon, R.E. ; et al.
Phys.Lett.B 452 (1999) 201-206, 1999.
Inspire Record 496157 DOI 10.17182/hepdata.34551

Direct photon production cross sections obtained in high statistics p ̄ p and pp collisions at s =24.3 GeV at the CERN SPS are used in a next-to-leading order QCD analysis. From the cross section difference σ( p ̄ p → γX)−σ(pp → γX) and quark distributions measured in deep inelastic scattering, a determination of the strong coupling constant, α s , is performed via a measurement of Λ (4) MS . This measurement yields a value Λ (4) MS = 210±22 ( stat. )±44 ( syst. ) +105 −36 ( theo. ) MeV. The corresponding value of α s expressed at M 2 Z is α s (M 2 Z )=0.1112 ±0.0016 ( stat. ) ±0.0033 ( syst. ) +0.0077 −0.0034 ( theo. ) .

1 data table match query

Value of LAMBDA(MSBAR) and ALPHAS at MZ**2 deduced from the difference in the pbar and p direct photon cross sections. The second systematic error is due to the uncertainties in the theory.


Spin Dependence of the Inclusive Reaction $p p$ (Polarized) $\to \pi^0 X$ at 24-{GeV}/$c$ for High $p_T \pi^0$ Produced in the Central Region

Antille, J. ; Dick, L. ; Madansky, L. ; et al.
Phys.Lett.B 94 (1980) 523-526, 1980.
Inspire Record 153785 DOI 10.17182/hepdata.27175

The spin dependence of π 0 inclusive production by 24 GeV/ c protons has been measured using a polarized target for Fhe Feynman x near 0 in the transverse momentum range 1.0 < p T < 2.5 GeV/ c . The results indicate a negative updown asymmetry growing strongly with p T and greater than 50% in absolute value for p T greater than 2 GeV/ c .

1 data table match query

No description provided.


A Measurement of the Inclusive $\pi^0$ and $\eta$ Production Cross-sections at High $p_T$ in $p \bar{p}$ and $p p$ Collisions at $\sqrt{s}=24$.3-{GeV}

The UA6 & CERN-Lausanne-Michigan-Rockefeller collaborations Antille, J. ; Baumann, S. ; Bernasconi, A. ; et al.
Phys.Lett.B 194 (1987) 568, 1987.
Inspire Record 247579 DOI 10.17182/hepdata.30119

Inclusive π 0 and η production at large transverse momentum were studied in both p̄p and pp interactions at √ s = 24.3 GeV. The experiment was performed using an internal molecular hydrogen gas jet target in the CERN SPS collider. No significant differences between production in p̄p and pp were observed in the transverse momentum range 2.5 < P T < 5.1 GeV/ c .

3 data tables match query

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Measurement of the inclusive J / psi production cross-sections in anti-p p and p p collisions at s**(1/2) = 24.3-GeV

The UA6 collaboration Morel, C. ; Bernasconi, A. ; Breedon, R.E. ; et al.
Phys.Lett.B 252 (1990) 505-510, 1990.
Inspire Record 300180 DOI 10.17182/hepdata.29505

The inclusive cross section times branching ratio for J/ψ→e + e − has been measured in the forward region in the UA6 experiment for p p and pp collisions at √ s = 24.3 GeV. The ratio of the pp to p p cross sections is found to be 0.76 ± 0.14 ± 0.06. This demonstrates that gluon-gluon fusion dominates over quark-antiquark annihilation in the formation of the c c state.

3 data tables match query

Extrapolation to full forward hemisphere (yrap > 0.0) uses the Bourquin-Gaillard parametrization (NP B114(76)334).

Extrapolation to full forward hemisphere (yrap > 0.0) uses the Bourquin-Gaillard parametrization (NP B114(76)334).

No description provided.


Direct Photon Production in Proton - Anti-proton Interactions at $\sqrt{s}=24$.3-{GeV}

The UA6 collaboration Bernasconi, A. ; Breedon, R.E. ; Camilleri, L. ; et al.
Phys.Lett.B 206 (1988) 163-168, 1988.
Inspire Record 261244 DOI 10.17182/hepdata.29982

Direct photons have been studied in pp̄ interactions at √ s = 24.3 GeV and in the transverse momentum ( p T ) range 3–7 GeV/ c (0.25 < x T < 0.58). The experiment was performed using an internal H 2 cluster the target in the CERN pp̄ Collider. The measured invariant cross section is compared with recent theoretical predictions.

2 data tables match query

No description provided.

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Direct photon cross sections in proton proton and antiproton proton interactions at s**(1/2) = 24.3-GeV.

The UA6 collaboration Ballocchi, G ; Breedon, R.E ; Camilleri, L ; et al.
Phys.Lett.B 436 (1998) 222-230, 1998.
Inspire Record 476703 DOI 10.17182/hepdata.49311

We report results on inclusive direct photon ( γ ), π 0 , and η production in both pp and p̄p interactions at s =24.3 GeV in the transverse momentum range 4.1≤ p T ≤7.7 GeV/ c and rapidity range −0.1≤ y ≤0.9. The data were collected between 1988 and 1990 by the UA6 experiment at CERN, which employed an internal H 2 gas jet target in the Sp̄pS collider. The inclusive direct photon cross sections and the cross section difference σ( p p )−σ( pp ) expressed as functions of p T ( γ ) are compared with next-to-leading order QCD predictions.

1 data table match query

PI0 cross sections. Direct photon cross section and pbar-p/p-p difference.


Charged Pion Production in $e^+ e^-$ Annihilation at 14-{GeV}, 22-{GeV} and 34-{GeV} Center-of-mass Energy

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 113 (1982) 98-104, 1982.
Inspire Record 176886 DOI 10.17182/hepdata.30892

The inclusive production of π ± mesons in e + e − annihilation has been measured at c.m. energies of 14, 22 and 34 GeV for pion momenta between 0.3 ans 10 GeV/ c . The fraction of pions among the charged hadrons is above 90% at 0.4 GeV/ c and decreases to about 50% at high momenta. The scaled cross sections ( s β ) d σ d x at 14, 22 and 34 GeV as well as the 5.2 GeV data from DASP have a rather similar x dependence. After integration over the x range from 0.2 to 0.6 the cross sections indicate a monotonic decrease with increasing centre-of-mass energy.

16 data tables match query

PION FRACTIONS IDENTIFIED BY INNER TOF COUNTERS (ITOF). ERRORS SHOWN ARE STATISTICAL ONLY.

PION FRACTIONS IDENTIFIED BY INNER TOF COUNTERS (ITOF). ERRORS SHOWN ARE STATISTICAL ONLY.

PION FRACTIONS IDENTIFIED BY INNER TOF COUNTERS (ITOF). ERRORS SHOWN ARE STATISTICAL ONLY.

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Direct photon production in anti-p p and p p interactions at s**(1/2) = 24.3-GeV

The UA6 collaboration Sozzi, G. ; Ballocchi, G. ; Bernasconi, A. ; et al.
Phys.Lett.B 317 (1993) 243-249, 1993.
Inspire Record 358422 DOI 10.17182/hepdata.28782

Inclusive direct photon invariant cross sections have been measured in both p p and pp collisions at √ s = 24.3 GeV at the CERN SPS, permitting the first measurement of the difference of the p p and pp cross sections. The direct photon cross section in p p collisions has been found to be systematically larger than that in pp collisions, which indicates a significant contribution of the q q annihilation term as predicted by theoretical calculations.

4 data tables match query

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Polarization of $\Sigma^+$ Hyperons Produced by 400 GeV Protons

Wilkinson, C. ; Handler, R. ; Lundberg, B. ; et al.
Phys.Rev.Lett. 46 (1981) 803-806, 1981.
Inspire Record 169869 DOI 10.17182/hepdata.20646

The polarization of 26 000 Σ+ hyperons produced by 400-GeV protons on Be has been measured. The polarizations of Σ+ and Λ hyperons have the opposite sign. The magnitude increases with momentum at 5-mrad production angle, and averages 22% over the momentum range 140 to 280 GeV/c.

2 data tables match query

No description provided.

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Muon-Deuterium Deep Inelastic Scattering

Kim, I.J. ; Entenberg, A. ; Jostlein, H. ; et al.
Phys.Rev.Lett. 33 (1974) 551, 1974.
Inspire Record 1427 DOI 10.17182/hepdata.21238

We have measured deep inelastic muon-deuteron scattering in the range 0.4<Q2<3.4 and 1.6<ν<5.6 GeV. We have extracted the neutron structure function and find that νW2n differs significantly from νW2p, as also found in e−d scattering. To compare μ−d and e−d scattering we form the ratio r(Q2)=(νW2)μd(νW2)ed=N(1+Q2Λ2)−2 and find N=0.925±0.038 and 1Λ2=−0.019±0.016.

1 data table match query

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