Breedon, R.E
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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
Table 1

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

Table 2

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

Table 3

No description provided.


A Measurement of the photon structure function F2

The AMY collaboration Sasaki, T. ; Yamagishi, Y. ; Tanaka, R. ; et al.
Phys.Lett.B 252 (1990) 491-498, 1990.
Inspire Record 299056 DOI 10.17182/hepdata.29524

The photon structure function F 2 has been measured at average Q 2 values of 73,160 and 390 ( GeV c ) 2 . We compare the x dependence of the Q 2 = 73 ( GeV c ) 2 data with theoretical expectations based on QCD. In addition we present results on the Q 2 evolution of the structure function for the intermediate x range (0.3⩽ x ⩽0.8). The results are consistent with QCD.

4 data tables match query
Table 1

X dependence at Q**2 = 73 GeV**2 for light quark data.

Table 2

X dependence at Q**2 = 73 GeV**2 for total data.

Table 3

Photon structure function F2 for total data.

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Jets in High Transverse Energy Events at the {CERN} Intersecting Storage Rings

The CMOR collaboration Angelis, A.L.S. ; Basini, G. ; Besch, H.J. ; et al.
Nucl.Phys.B 244 (1984) 1-22, 1984.
Inspire Record 202452 DOI 10.17182/hepdata.33870

Most events with high neutral transverse energy, E T 0 , produced in pp colisions at √ s = 62.3 GeV, are jet-like. The evidence for this is presented, based on data collected using an electromagnetic calorimeter covering 90% of 2π in azimuth. The spectrum d N /d E T 0 has been measured over the E T 0 range from 10 to 35 GeV. Properties of the observed jets are discussed.

1 data table match query
Table 1

No description provided.


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
Table 1

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.


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
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Large Transverse Momentum $\pi^0$ Production in $\alpha \alpha d d$ and $p p$ Collisions at the {CERN} {ISR}

The BCMOR collaboration Angelis, A.L.S. ; Basini, G. ; Besch, H.J. ; et al.
Phys.Lett.B 185 (1987) 213-217, 1987.
Inspire Record 222768 DOI 10.17182/hepdata.30194

None

1 data table match query
Table 1

No description provided.


Direct Photon Production at the {CERN} {ISR}

The CMOR collaboration Angelis, A.L.S. ; Basini, G. ; Besch, H.J. ; et al.
Nucl.Phys.B 327 (1989) 541-568, 1989.
Inspire Record 279988 DOI 10.17182/hepdata.33181

A measurement of direct photon production in pp collisions at a center of mass energy ∝ s =63 GeV is reported. Arrays of lead-glass calorimeters and multiwire proportional chambers were used as photon detectors. Data are presented in the transverse momentum range from 4.5 to 10 GeV/ c and compared with QCD predictions. The event structure of this sample is compared with that of a set dominated by high transverse momentum π O ́ ' s .

3 data tables match query
Table 1

Final Average Results from inside and outside detector.

Table 2

Results for the inside detector.

Table 3

Results for the outside detector.


High Transverse Energy and High Transverse Momentum Events in $p \bar{p}$ and $p p$ Interactions at the {CERN} Intersecting Storage Rings

The CMOR collaboration Angelis, A.L.S. ; Basini, G. ; Besch, H.J. ; et al.
Nucl.Phys.B 263 (1986) 228-244, 1986.
Inspire Record 216800 DOI 10.17182/hepdata.33698

A comparison between p p and pp interactions at √ s = 52.7 GeV is presented for a total neutral transverse energy ( E T o ) trigger and for a high transverse momentum ( p T ) neutral cluster trigger. The rate of production of events in the range 6< E T o <20 GeV is observed to be 10% higher in p p collisions than in pp collisions. A study of the structure of the events shows this excess to be due to more isotropic events being produced in p p collisions. The ratio of the production cross section for single neutral clusters in p p and pp interactions in the range 1.25< p T <10 GeV/ c does not significantly differ from unity.

1 data table match query
Table 1

No description provided.


A Study of massive electron pairs and associated particles produced at the CERN ISR

The CERN-Michigan State-Oxford-Rockefeller collaboration Angelis, A.L.S. ; Basini, G. ; Besch, H.J. ; et al.
Nucl.Phys.B 348 (1991) 1-22, 1991.
Inspire Record 298427 DOI 10.17182/hepdata.33054

A sample of 105 e + e − events with an invariant mass greater than 11 GeV/ c 2 produced in pp collisions at a center-of-mass energy of 62.3 GeV is discussed. Cross sections are presented as a function of mass and transverse momentum. The multiplicity, transverse momentum, and azimuthal dependence of associated particles are also studied.

3 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Precise Comparison of Anti-proton - Proton and Proton Proton Forward Elastic Scattering at $\sqrt{s}=24$.3-{GeV}

The UA6 collaboration Breedon, R.E. ; Chapin, T.J. ; Cool, R.L. ; et al.
Phys.Lett.B 216 (1989) 459-465, 1989.
Inspire Record 267044 DOI 10.17182/hepdata.29854

We report results from a measurement of antiproton-proton and proton-proton small-angle elastic scattering at √ s = 24.3 GeV in the range 0.001 ⩽ | t | ⩽ 0.06 (GeV/ c ) 2 . The measurement was performed at the CERN p p Collider by using silicon detectors to observe protons recoiling from a hydrogen cluster-jet target intercepting the stored p and p beams. Fits to the measured differential cross sections yield the ratio of the real to the imaginary part of the forward nuclear scattering amplitude ρ and the nuclear slope parameter b for both p p and pp. We find that the difference Δρ = ρ ( p p ) − ρ( pp ) = 0.031 ± 0.010 agrees with conventional fits and disagrees with the “odderon” fit designed to accommodate the recent UA4 measurement of ρ( p p) at 546 GeV.

3 data tables match query
Table 1

Data requested from authors.

Table 2

No description provided.

Table 3

Nuclear slopes fixed to world average.