A Determination of the Pion Structure Function from Muon Pair Production

Newman, C.B. ; Anderson, K.J. ; Coleman, R.N. ; et al.
Phys.Rev.Lett. 42 (1979) 951, 1979.
Inspire Record 140037 DOI 10.17182/hepdata.20767

Data on muon-pair production by pions are used to determine the momentum distribution for valence quarks in the pion. The shape of a nucleon structure function is also obtained and is compared with a calculation based on existing data.

1 data table

No description provided.


Observation of Double phi Meson Production in 400-GeV/c Proton - Nucleon Interactions

Davenport, T.F. ; Albright, John R. ; Goldman, J.H. ; et al.
Phys.Rev.D 33 (1986) 2519, 1986.
Inspire Record 218616 DOI 10.17182/hepdata.23536

The production of φ-meson pairs has been observed in 400-GeV/c proton-nucleon interactions at the Fermilab multiparticle spectrometer in the inclusive reaction pN→φφ+X, where each φ decays to a K+K− pair. A fast (200 nsec) high-level processor was used to selectively trigger on events containing two pairs of oppositely charged kaons having low invariant masses. The experimental apparatus and trigger processor are described. The cross section for φφ production and an upper limit for ηc production are presented.

1 data table

No description provided.


Charged-particle multiplicity measurement in proton-proton collisions at sqrt(s) = 7 TeV with ALICE at LHC

The ALICE collaboration Aamodt, K. ; Abel, N. ; Abeysekara, U. ; et al.
Eur.Phys.J.C 68 (2010) 345-354, 2010.
Inspire Record 852264 DOI 10.17182/hepdata.54795

The pseudorapidity density and multiplicity distribution of charged particles produced in proton-proton collisions at the LHC, at a centre-of-mass energy $\sqrt{s} = 7$ TeV, were measured in the central pseudorapidity region |$\eta$| < 1. Comparisons are made with previous measurements at $\sqrt{s}$ = 0.9 TeV and 2.36 TeV. At $\sqrt{s}$ = 7 TeV, for events with at least one charged particle in |$\eta$| < 1, we obtain dNch/deta = 6.01 $\pm$ 0.01 (stat.) $^{+0.20}_{-0.12}$ (syst.). This corresponds to an increase of 57.6% $\pm$ 0.4% (stat.) $^{+3.6}_{-1.8}$% (syst.) relative to collisions at 0.9 TeV, significantly higher than calculations from commonly used models. The multiplicity distribution at 7 TeV is described fairly well by the negative binomial distribution.

6 data tables

Charged-particle pseudorapidity densities at central pseudorapidity (ETRAP from -1.0 to 1.0) for the INEL>0 class of events. Data are also given for the lower energy ALICE data.

Relative increase in pseudorapidity density between the different energies.

Multiplicity distribution normalized to the bin width in the pseudorapidity region -1.0 to 1.0 for INEL>0 collisions at a centre-of-mass energy of 7000 GeV. See the paper arXiv:1004.3034 for the lower energy data. Note that the statistical as well as the systematic uncertainties are strongly correlated between neighbouring points. See text of paper for details.

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