HEPData Search

Showing 10 of 5898 results

HADRON MULTIPLICITY VARIATION WITH Q**2 AND SCALE BREAKING OF THE HADRON DISTRIBUTIONS IN DEEP INELASTIC MUON - PROTON SCATTERING

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.

Phys.Lett.B 165 (1985) 222-228, 1985.

Inspire Record 217810 DOI 10.17182/hepdata.30328

Measurements are presented of the variation with Q 2 (scaling violation) of the hadron multiplicity in deep inelastic muon-proton scattering. An increase in the average multiplicity of both the charged hadrons and K 0 mesons is observed with increasing Q 2 or x Bj for fixed centre-of-mass energy W . The study of the shape of the effective fragmentation function D h ( z , W , Q 2 ) shows that the increase of the particle yield with Q 2 takes place for low z particles. The variation of the hadron distributions with Q 2 is also studied in the current fragmentation region where a decrease in multiplicity is observed. Such effects are expected from QCD.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Inclusive Charged Particle Production Near the Kinematic Limit in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Kooijman, P. ; Loos, J.S. ; et al.

Phys.Lett.B 164 (1985) 199-202, 1985.

Inspire Record 17255 DOI 10.17182/hepdata.30327

Inclusive production of charged particles has been studied in e + e − annihilation at s s=29 GeV using the high resolution spectrometer at PEP. Differential cross sections are presented in the range of scaled energy 0.1< z <1.0. The data for z <0.5 show the (1− z ) 2 behavior predicted by the dimensional counting rules. Comparisons are made with predictions of the Lund string model and the Webber cluster model.

1 data table

Table 1

Data requested from authors.

MEAN CHARACTERISTICS OF SECONDARY PARTICLES IN CUMULATIVE pi- C INTERACTIONS AT 40-GeV/c

Baatar, Ts. ; Lyubimov, V.B. ; Serdamba, L. ; et al.

JINR-P1-85-698, 1985.

Inspire Record 221159 DOI 10.17182/hepdata.39007

None

8 data tables

Table 1

EVENTS HAVE ONE OR MORE CUMULATIVE PIONS.

Table 2

EVENTS HAVE ONE OR MORE CUMULATIVE PROTONS.

Table 3

EVENTS HAVE ONE OR MORE CUMULATIVE PIONS AND ONE OR MORE CUMULATIVE PROTONS.

More…

rivet Analysis
Charged Meson Pair Production in $\gamma \gamma$ Interactions

Boyer, J. ; Burke, D.L. ; Butler, F. ; et al.

Phys.Rev.Lett. 56 (1986) 207, 1986.

Inspire Record 220003 DOI 10.17182/hepdata.20236

The cross section for the production of π+π− or K+K− pairs in γγ interactions is measured for mππ between 1.7 and 3.5 GeV/c2 and for two intervals of γγ center-of-mass scattering angle. Results are compared with predictions of a QCD model.

2 data tables

Table 1

Data read off graph.

Table 2

Data read off graph.

A Study of the Inclusive $K_s^0$, $\Lambda$, $\bar{\Lambda}$ Production in Diffractive $\gamma$P Interactions

Bhadra, S. ; Appel, J.A. ; Bartlett, D.F. ; et al.

Phys.Rev.Lett. 55 (1985) 2749, 1985.

Inspire Record 217669 DOI 10.17182/hepdata.20275

We have studied inclusive KS, Λ, and Λ¯ photoproduction over the ranges 40<Eγ<170 GeV and forward produced mass 2<MF<10 GeV. We observe equal Λ and Λ¯ production rates and spectra as expected in a diffractive process where the target proton remains unaltered. We show that the fraction of hadronic events with a strange particle produced in events with forward mass MF agrees well with the same measurement in e+e− annihilation at a center-of-mass energy Ec.m.=MF. The x=2PMF distributions of these three particles in the forward-mass rest frame are compared with theoretical predictions.

1 data table

Table 1

No description provided.

Measurement of the $K^0^*$ (896) Radiative Width

Carlsmith, D. ; Bernstein, R.H. ; Bock, G.J. ; et al.

Phys.Rev.Lett. 56 (1986) 18, 1986.

Inspire Record 217703 DOI 10.17182/hepdata.20252

Primakoff production of the K0*(896) by incident KL’s was observed in the energy range 100–200 GeV. Production from Cu and Pb targets was measured simultaneously leading to a new value for the K0*(896) radiative width Γ(K0*(896)→K0+γ) of 116.5±9.9 keV. The result agrees with a previous determination while being considerably more precise and allows for more stringent tests of quark-model relations among the radiative widths of the low-lying vector mesons.

1 data table

Table 1

Data requested from authors.

Observation of a Narrow K anti-K State in J/psi Radiative Decays

The MARK-III collaboration Baltrusaitis, R.M. ; Becker, J. ; Blaylock, G. ; et al.

Phys.Rev.Lett. 56 (1986) 107, 1986.

Inspire Record 217856 DOI 10.17182/hepdata.20254

Evidence is presented for a narrow state, called ξ, in the decay modes J/ψ→γξ, ξ→K+K−, and ξ→KS0KS0. In the K+K− mode, the ξ has a mass of 2.230±0.006±0.014 GeV/c2, a width of Γ=0.026−0.016+0.020± 0.017 GeV/c2, a product branching ratio of (4.2−1.4+1.7±0.8)×10 −5, and a statistical significance of ∼4.5 standard deviations. In the KS0KS0 mode, it has a mass of 2.232±0.007±0.007 GeV/c2, a width of Γ=0.018−0.015+0.023± 0.010 GeV/c2, a product branching ratio of (3.1−1.3+1.6±0.7)×10 −5, and a statistical significance of ∼3.6 standard deviations. Limits on ξ decay to other final states are presented.

1 data table

Table 1

No description provided.

A Measurement of Nuclear Effects in Deep Inelastic Muon Scattering on Deuterium, Nitrogen and Iron Targets

The BCDMS collaboration Bari, G. ; Benvenuti, A.C. ; Bollini, D. ; et al.

Phys.Lett.B 163 (1985) 282, 1985.

Inspire Record 216817 DOI 10.17182/hepdata.30331

New data is presented on the ratios of structure functions F 2 ( x , Q 2 ) measured in deep inelastic muon scattering with deuterium, nitrogen, and iron targets. The existence of nuclear effects at large Q 2 is confirmed with improved systematic accuracy. The ratio F 2 Fe ( x ) F 2 D 2 ( x ) covers the range 0.20 ⩽ x ⩽ 0.70 and is in agreement with earlier measurements. The ratio F 2 N 2 ( x )/ F 2 D 2 ( x ) is measured over the range 0.08 ⩽ x ⩽ 0.70 and is compatible with unity below x = 0.3.

2 data tables

Table 1

VALUES OF Q2 CORRESPONDING TO THE X-BINS IN THIS TABLE ARE:- 46-106,46-106,53-150,53-200,70-200,80-200 RESPECTIVELY.

Table 2

VALUES OF Q2 CORRESPONDING TO THE X-BINS IN THIS TABLE ARE:- 26-40,26-61,30-80,30-106,30-106,30-150,30-200,35-200,46-200.

Comparison of Light Quark and Charm Quark Fragmentation

Kesten, P. ; Akerlof, C. ; Bonvicini, G. ; et al.

Phys.Lett.B 161 (1985) 412-416, 1985.

Inspire Record 17116 DOI 10.17182/hepdata.30349

Separate samples of charm quark and light quark (u, d, s) jets have been isolated in an experiment studying e + e − annihilations at s = 29 GeV . The results come from data corresponding to an integrated luminosity of 111 pb −1 collected by the High Resolution Spectrometer. Differences were observed in charged multiplicities, momentum distributions, and rapidity of the size expected from the different fragmentation functions and leading particle decay properties of the two samples.

3 data tables

Table 1

Charm Quark Jet Trigger. Characteristics of Jet Opposite the Trigger Jet.

Table 2

Light Quark Jet Trigger. Characteristics of Jet Opposite the Trigger Jet.

Table 3

No description provided.