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Hadron Production by $e^+ e^-$ Annihilation at Center-of-mass Energies Between 2.6-{GeV} and 7.8-{GeV}. Part 2. Jet Structure and Related Inclusive Distributions

Hanson, G. ; Alam, M.S. ; Boyarski, A. ; et al.

Phys.Rev.D 26 (1982) 991, 1982.

Inspire Record 170499 DOI 10.17182/hepdata.38162

We present results on the jet structure observed in multihadronic events produced by e+e− annihilation in the Mark I magnetic detector at SPEAR. The evidence for jet structure and the jet-axis angular distribution are reported. We give inclusive distributions of the hadrons in Feynman x, rapidity, and transverse momentum relative to the jet axis.

19 data tables

Table 1

Observed particle PT with respect to jet axis for events with three or more detected charged particles.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of the Inclusive Jet Cross-Section at the CERN p anti-p Collider

The UA1 collaboration Arnison, G. ; Albrow, M.G. ; Allkofer, O.C. ; et al.

Phys.Lett.B 172 (1986) 461-466, 1986.

Inspire Record 228112 DOI 10.17182/hepdata.30262

The inclusive jet cross section has been measured in the UA1 experiment at the CERN p p Collider at centre-of-mass energies √ s = 546 GeV and √ s = 630 eV. The cross sections are found to be consistent with QCD predictions, The observed change in the cross section with the centre-of-mass energy √ s is accounted for in terms of x T scaling.

1 data table

Table 1

No description provided.

DOUBLE PROMPT PHOTON PRODUCTION AT HIGH TRANSVERSE MOMENTUM BY pi- ON PROTONS AT 280-GeV/c

The WA70 collaboration Bonvin, E. ; Bopp, R. ; Carroll, L.J. ; et al.

Z.Phys.C 41 (1989) 591, 1989.

Inspire Record 265091 DOI 10.17182/hepdata.15470

A search for pairs of highpT prompt photons produced in hydrogen by a 280 GeV/c incidentπ- beam has been carried out using a fine-grained electromagnetic calorimeter and the Omega spectrometer at the CERN SPS. Clear evidence for the existence of such events is found with a six standard deviation signal forpT>3.0 GeV/c. The cross-sections are consistent with beyond leading order QCD calculations. A discussion on the determination of αs is also presented.

2 data tables

Table 1

PT is the transverse momentum of either of the two photons.

Table 2

PT is the transverse momentum of either of the two photons.

Production of K0 and Lambda in hadronic Z decays

The ALEPH collaboration Buskulic, D. ; Casper, D. ; De Bonis, I. ; et al.

Z.Phys.C 64 (1994) 361-374, 1994.

Inspire Record 375060 DOI 10.17182/hepdata.48239

Measurements of the inclusive cross-sections forK0 and Λ production in hadronic decays of the Z are presented together with measurements of two-particle correlations within pairs of Λ andK0. The results are compared with predictions from the hadronization models Jetset, based on string fragmentation, and Herwig, based on cluster decays. TheK0 spectrum is found to be harder than predicted by both models, while the Λ spectrum is softer than predicted. The correlation measurements are all reproduced well by Jetset, while Herwig misses some of the qualitative features and overestimates the size of the$\Lambda \bar \Lambda $ correlation. Finally, the possibility of Bose-Einstein correlation in theKS0KS0 system is discussed.

7 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of the B meson differential cross-section, d sigma / d p(T), in p anti-p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amendolia, S.R. ; et al.

Phys.Rev.Lett. 75 (1995) 1451-1455, 1995.

Inspire Record 393552 DOI 10.17182/hepdata.42432

This paper presents the first direct measurement of the $B$ meson differential cross section, $d\sigma/dp_T$, in $p\overline{p}$ collisions at $\sqrt{s}=1.8$ TeV using a sample of $19.3 \pm 0.7$ pb$~{-1}$ accumulated by the Collider Detector at Fermilab (CDF). The cross section is measured in the central rapidity region $|y| < 1$ for $p_T(B) > 6.0$ GeV/$c$ by fully reconstructing the $B$ meson decays $B~{+}\rightarrow J/\psi K~{+}$ and $B~{0}\rightarrow J/\psi K~{*0}(892)$, where $J/\psi \rightarrow \mu~+\mu~-$ and $K~{*0} \rightarrow K~+ \pi~-$. A comparison is made to the theoretical QCD prediction calculated at next-to-leading order.

3 data tables

Table 1

Charged B meson cross section.

Table 2

Average B meson cross section (including charged and neutral).

Table 3

Total integrated B meson cross section above 6 GeV.

Inclusive parton cross-sections in photoproduction and photon structure

The H1 collaboration Ahmed, T. ; Aid, S. ; Andreev, V. ; et al.

Nucl.Phys.B 445 (1995) 195-218, 1995.

Inspire Record 394176 DOI 10.17182/hepdata.44975

Photoproduction of 2-jet events is studied with the H1 detector at HERA. Parton cross sections are extracted from the data by an unfolding method using leading order parton-jet correlations of a QCD generator. The gluon distribution in the photon is derived in the fractional momentum range $0.04\le x_\gamma \le 1$ at the average factorization scale $75$ GeV$~2$.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

Gluon density of the photon (alpha is the fine structure constant).

Measurement of the upsilon cross-section at D0 using dimuons

The D0 collaboration Abachi, S. ; Abbott, B. ; Abolins, M. ; et al.

FERMILAB-CONF-95-206-E, 1995.

Inspire Record 397850 DOI 10.17182/hepdata.43051

None

1 data table

Table 1

Cross section times the branching ratio for decay into dimuons.

Inclusive muon and B quark production cross-sections in p anti-p collisions at s**(1/2) = 1.8-TeV

The D0 collaboration Abachi, S. ; Abbott, B. ; Abolins, M. ; et al.

(1995), 1995.

Inspire Record 398709 DOI 10.17182/hepdata.43027

We have calculated the double and triple differential cross sections for electron ejection with energy of 14.6 eV in single ionization of H2 by 75 keV proton impact. A molecular version of the continuum distorted wave-eikonal initial state approach is applied, where the interaction between the projectile and the residual molecular ion is considered more properly than in previous applications of the method. For triple differential cross sections, the present results are in better agreement with the experimental data than those of other descriptions when large momentum transfer values are considered. For double differential cross sections the experimental data are reproduced quite well for both coherent and incoherent proton beams.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

J / psi production in p anti-p collisions at s**(1/2) = 1.8-TeV

The D0 collaboration Abachi, S. ; Abbott, B. ; Abolins, M. ; et al.

Phys.Lett.B 370 (1996) 239-248, 1996.

Inspire Record 415417 DOI 10.17182/hepdata.42319

We have studied J ψ production in p p collisions at s = 1.8 TeV with the DØ detector at Fermilab using μ + μ − data. We have measured the inclusive J ψ production cross section as a function of J ψ transverse momentum, p T . For the kinematic range p T > 8 GeV/ c and |η| < 0.6 we obtain σ(p p → J ψ + X) · Br ( J ψ → μ + μ − ) = 2.08 ± 0.17( stat) ± 0.46(syst) nb. Using the muon impact parameter we have estimated the fraction of J ψ mesons coming from B meson decays to be f b = 0.35 ± 0.09(stat)±0.10(syst) and inferred the inclusive b production cross section. From the information on the event topology the fraction of nonisolated J ψ events has been measured to be f nonisol = 0.64 ± 0.08(stat)±0.06(syst). We have also obtained the fraction of J ψ events resulting from radiative decays of χ c states, f χ = 0.32 ± 0.07(stat)±0.07(syst). We discuss the implications of our measurements for charmonium production processes.

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

Integrated b-quark production cross section.