Measurements of e+ e- ---> K+ K- eta, K+ K- pi0 and K0(s) K+- pi-+ cross- sections using initial state radiation events

The BaBar collaboration Aubert, Bernard ; Bona, M. ; Boutigny, D. ; et al.
Phys.Rev.D 77 (2008) 092002, 2008.
Inspire Record 765258 DOI 10.17182/hepdata.50372

This paper reports measurements of processes: e+e- -> gamma KsK+pi-, e+e- -> gamma K+K-pi0, e+e- -> gamma phi eta, and e+e- -> gamma phi pi0. The initial state radiated photon allows to cover the hadronic final state in the energy range from thresholds up to ~4.6 GeV. The overall size of the data sample analyzed is 232 fb-1, collected by the BaBar detector running at the PEP-II e+e- storage ring. From the Dalitz plot analysis of the KsK+pi- final state, moduli and relative phase of the isoscalar and the isovector components of the e+e- -> K K*(892) cross section are determined. Parameters of phi and rho recurrences are also measured, using a global fitting procedure which exploits the interconnection among amplitudes, moduli and phases of the e+e- -> KsK+pi-, K+K-pi0, phi eta final states. The cross section for the OZI-forbidden process e+e- -> phi pi0, and the J/psi branching fractions to KK*(892) and K+K-eta are also measured.

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The $e^+ e^-\to 2(\pi^+\pi^-)\pi^0$, 2(\pi^+\pi^-)\eta$, $K^+ K^-\pi^+\pi^-\pi^0$ and $K^+ K^-\pi^+\pi^-\eta$ Cross Sections Measured with Initial-State Radiation

The BaBar collaboration Aubert, Bernard ; Bona, M. ; Boutigny, D. ; et al.
Phys.Rev.D 76 (2007) 092005, 2007.
Inspire Record 758568 DOI 10.17182/hepdata.51824

We study the processes $e^+ e^-\to 2(\pi^+\pi^-)\pi^0\gamma$, $2(\pi^+\pi^-)\eta\gamma$, $K^+ K^-\pi^+\pi^-\pi^0\gamma$ and $K^+ K^-\pi^+\pi^-\eta\gamma$ with the hard photon radiated from the initial state. About 20000, 4300, 5500 and 375 fully reconstructed events, respectively, are selected from 232 fb$^{-1}$ of BaBar data. The invariant mass of the hadronic final state defines the effective $e^+ e^-$ center-of-mass energy, so that the obtained cross sections from the threshold to about 5 GeV can be compared with corresponding direct \epem measurements, currently available only for the $\eta\pi^+\pi^-$ and $\omega\pi^+\pi^-$ submodes of the $e^+ e^-\to 2(\pi^+\pi^-)\pi^0$ channel. Studying the structure of these events, we find contributions from a number of intermediate states, and we extract their cross sections where possible. In particular, we isolate the contribution from $e^+ e^-\to\omega(782)\pi^+\pi^-$ and study the $\omega(1420)$ and $\omega(1650)$ resonances. In the charmonium region, we observe the $J/\psi$ in all these final states and several intermediate states, as well as the $\psi(2S)$ in some modes, and we measure the corresponding branching fractions.

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The $e^+ e^-\to K^+ K^- \pi^+\pi^-$, $K^+ K^- \pi^0\pi^0$ and $K^+ K^- K^+ K^-$ Cross Sections Measured with Initial-State Radiation

The BaBar collaboration Aubert, Bernard ; Bona, M. ; Boutigny, D. ; et al.
Phys.Rev.D 76 (2007) 012008, 2007.
Inspire Record 747875 DOI 10.17182/hepdata.50373

We study the processes $e^+ e^-\to K^+ K^- \pi^+\pi^-\gamma$, $K^+K^-\pi^0\pi^0\gamma$ and $K^+ K^- K^+ K^-\gamma$, where the photon is radiated from the initial state. About 34600, 4400 and 2300 fully reconstructed events, respectively, are selected from 232 \invfb of \babar data. The invariant mass of the hadronic final state defines the effective \epem center-of-mass energy, so that the $K^+ K^- \pi^+\pi^-\gamma$ data can be compared with direct measurements of the $e^+ e^-\to K^+K^- \pipi$ reaction/ no direct measurements exist for the $e^+ e^-\to K^+ K^- \pi^0\pi^0$ or $\epem\to K^+ K^- K^+ K^-$ reactions. Studying the structure of these events, we find contributions from a number of intermediate states, and we extract their cross sections where possible. In particular, we isolate the contribution from $e^+ e^-\to\phi(1020) f_{0}(980)$ and study its structure near threshold. In the charmonium region, we observe the $J/\psi$ in all three final states and several intermediate states, as well as the $\psi(2S)$ in some modes, and measure the corresponding branching fractions. We see no signal for the Y(4260) and obtain an upper limit of $\BR_{Y(4260)\to\phi\pi^+\pi^-}\cdot\Gamma^{Y}_{ee}<0.4 \ev$ at 90% C.L.

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Study of the Exclusive Initial-State-Radiation Production of the DDbar System

The BaBar collaboration Aubert, Bernard ; Bona, M. ; Boutigny, D. ; et al.
SLAC-PUB-12818, 2008.
Inspire Record 776519 DOI 10.17182/hepdata.18803

A search for charmonium and other new states is performed in a study of exclusive initial-state-radiation production of D Dbar events from electron-positron annihilations at a center-of-mass energy of 10.58 GeV. The data sample corresponds to an integrated luminosity of 384 fb-1 and was recorded by the BABAR experiment at the PEP-II storage ring. The D Dbar mass spectrum shows clear evidence of the psi(3770) plus other structures near 3.9, 4.1, and 4.4 GeV/c^2. No evidence for Y(4260) -> D Dbar is observed, leading to an upper limit of B(Y(4260) -> D Dbar)/B(Y(4260) -> J/psi pi+ pi-) < 1.0 at 90 % confidence level.

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Evidence of a broad structure at an invariant mass of 4.32- GeV/c**2 in the reaction e+ e- ---> pi+ pi- psi(2S) measured at BaBar

The BaBar collaboration Aubert, Bernard ; Barate, R. ; Bona, M. ; et al.
Phys.Rev.Lett. 98 (2007) 212001, 2007.
Inspire Record 729388 DOI 10.17182/hepdata.19344

We present a measurement of the cross section of the process $e^+e^-\to\pi^+pi^-\psi(2S)$ from threshold up to 8 GeV center-of-mass energy using events containing initial-state radiation, produced at the PEP-II $e^+e^-$ storage rings. The study is based on 298 fb$^{-1}$ of data recorded with the BaBar detector. A structure is observed in the cross-section not far above threshold, near 4.32 GeV. We also investigate the compatibility of this structure with the Y(4260) previously reported by this experiment.

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Measurement of inclusive production of neutral hadrons from Z decays

The L3 collaboration Acciarri, M. ; Adam, A. ; Adriani, O. ; et al.
Phys.Lett.B 328 (1994) 223-233, 1994.
Inspire Record 374698 DOI 10.17182/hepdata.48189

We present a study of the inclusive production of π 0 , η, K s 0 and Λ based on 929,000 hadronic Z decays recorded with the L3 detector at LEP. The measured inclusive momentum distributions have been compared with predictions from parton shower models as well as an analytical Quantum Chromodynamics calculation. Comparing to low energy e + e - data, we find that QCD describes the energy evolution of the hadron spectrum.

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Observation of the Exclusive Reaction e+ e- ---> phi eta at s**(1/2) = 10.58-GeV

The BaBar collaboration Aubert, Bernard ; Bona, M. ; Boutigny, D. ; et al.
Phys.Rev.D 74 (2006) 111103, 2006.
Inspire Record 731865 DOI 10.17182/hepdata.52608

We report the observation of $\e^+e^-\to \phi\eta$ near $\sqrt{s}$ = 10.58 GeV with 6.5 $\sigma$ significance in the $K^+K^-\gamma\gamma$ final state in a data sample of 224 $fb^{-1}$ collected by the BaBar experiment at the PEP-II $e^+e^-$ storage rings. We measure the restricted radiation-corrected cross section to be $\sigma(\e^+e^- \to \phi \eta) =$$2.1\pm 0.4 (\mathrm{stat})\pm 0.1(\mathrm{syst}) \mathrm{fb}$ within the range $|\cos\theta^*| < 0.8$, where $\theta^*$ is the center-of-mass polar angle of the $\phi$ meson. The $\phi$ meson is required to be in the invariant mass range of 1.008 $< m_{\phi} <$ 1.035 \gevcc. The radiation-corrected cross section in the full $\cos\theta^*$ range is extrapolated to be $2.9\pm 0.5 (\mathrm{stat})\pm 0.1(\mathrm{syst}) \mathrm{fb}$.

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Measurement of the eta and eta' transition form factors at q**2 = 112-GeV**2.

The BaBar collaboration Aubert, Bernard ; Barate, R. ; Bona, M. ; et al.
Phys.Rev.D 74 (2006) 012002, 2006.
Inspire Record 716277 DOI 10.17182/hepdata.22085

We report a study of the processes e+e- -> eta gamma and e+e- -> etaprime gamma at a center-of-mass energy of 10.58 GeV, using a 232 fb^-1 data sample collected with the BABAR detector at the PEP-II collider at SLAC. We observe 20+6-5 eta gamma and 50+8-7 etaprime gamma events over small backgrounds, and measure the cross sections sigma(e+e- -> eta gamma) =4.5+1.2-1.1(stat)+-0.3(sys) fb and sigma(e+e- -> etaprime gamma)=5.4+-0.8(stat)+-0.3(sys) fb. The corresponding transition form factors at q^2 = 112 GeV^2 are q^2|F_eta(q^2)|=0.229+-0.030+-0.008 GeV, and q^2|F_etaprime(q^2)|=0.251+-0.019+-0.008 GeV, respectively.

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The e+ e- ---> 3(pi+ pi-), 2(pi+ pi- pi0) and K+ K- 2(pi+ pi-) cross sections at center-of-mass energies from production threshold to 4.5-GeV measured with initial-state radiation

The BaBar collaboration Aubert, Bernard ; Barate, R. ; Boutigny, D. ; et al.
Phys.Rev.D 73 (2006) 052003, 2006.
Inspire Record 709730 DOI 10.17182/hepdata.41843

We study the processes e+ e- --> 3(pi+pi-)gamma, 2(pi+pi-pi0)gamma and K+ K- 2(pi+pi-)gamma, with the photon radiated from the initial state. About 20,000, 33,000 and 4,000 fully reconstructed events, respectively, have been selected from 232 fb-1 of BaBar data. The invariant mass of the hadronic final state defines the effective e+e- center-of-mass energy, so that these data can be compared with the corresponding direct e+e- measurements. From the 3(pi+pi-), 2(pi+pi-pi0) and K+ K- 2(pi+pi-) mass spectra, the cross sections for the processes e+ e- --> 3(pi+pi-), e+ e- --> 2(pi+pi-pi0) and e+ e- --> K+ K- 2(pi+pi-) are measured for center-of-mass energies from production threshold to 4.5 GeV. The uncertainty in the cross section measurement is typically 6-15%. We observe the J/psi in all these final states and measure the corresponding branching fractions.

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A Study of e+ e- ---> p anti-p using initial state radiation with BABAR

The BaBar collaboration Aubert, Bernard ; Barate, R. ; Boutigny, D. ; et al.
Phys.Rev.D 73 (2006) 012005, 2006.
Inspire Record 700020 DOI 10.17182/hepdata.41831

The e+e- -> p anti-p cross section is determined over a range of p anti-p masses, from threshold to 4.5 GeV/c^2, by studying the e+e- -> p anti-p gamma process. The data set corresponds to an integrated luminosity of 232 fb^-1, collected with the BABAR detector at the PEP-II storage ring, at an e+e- center-of-mass energy of 10.6 GeV. The mass dependence of the ratio of electric and magnetic form factors, |G_E/G_M|, is measured for p anti-p masses below 3 GeV/c^2: its value is found to be significantly larger than 1 for masses up to 2.2 GeV/c^2. We also measure J/psi -> p anti-p and psi(2S) -> p anti-p branching fractions and set an upper limit on Y(4260) -> p anti-p production and decay.

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Determination of alpha-s from jet multiplicities measured on the Z0 resonance

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 248 (1990) 464-472, 1990.
Inspire Record 298078 DOI 10.17182/hepdata.29651

We present a study of jet multiplicities based on 37 000 hadronic Z 0 boson decays. From this data we determine the strong coupling constant α s =0.115±0.005 ( exp .) −0.010 +0.012 (theor.) to second order QCD at √ s =91.22GeV.

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Studies of hadronic event structure and comparisons with QCD models at the Z0 resonance

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Z.Phys.C 55 (1992) 39-62, 1992.
Inspire Record 334954 DOI 10.17182/hepdata.14566

The structure of hadronic events fromZ0 decay is studied by measuring event shape variables, factorial moments, and the energy flow distribution. The distributions, after correction for detector effects and initial and final state radiation, are compared with the predictions of different QCD Monte Carlo programs with optimized parameter values. These Monte Carlo programs use either the second order matrix element or the parton shower evolution for the perturbative QCD calculations and use the string, the cluster, or the independent fragmentation model for hadronization. Both parton shower andO(α2s matrix element based models with string fragmentation describe the data well. The predictions of the model based on parton shower and cluster fragmentation are also in good agreement with the data. The model with independent fragmentation gives a poor description of the energy flow distribution. The predicted energy evolutions for the mean values of thrust, sphericity, aplanarity, and charge multiplicity are compared with the data measured at different center-of-mass energies. The parton shower based models with string or cluster fragmentation are found to describe the energy dependences well while the model based on theO(α2s calculation fails to reproduce the energy dependences of these mean values.

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B* production in Z decays at LEP

The L3 collaboration Acciarri, M. ; Adam, A. ; Adriani, O. ; et al.
Phys.Lett.B 345 (1995) 589-597, 1995.
Inspire Record 381046 DOI 10.17182/hepdata.48342

The production of B ∗ mesons in Z decays has been measured at LEP with the L3 detector. A sample of Z → b b events was obtained by tagging muons in 1.6 million hadronic Z decays collected in 1991, 1992 and 1993. A signal with a peak value of E γ = 46.3 ± 1.9 (stat) MeV in the B rest frame energy spectrum was interpreted to come from the decay B ∗ → γB. The inclusive production ratio of B ∗ mesons relative to B mesons was determined from a fit to the spectrum to be N B ∗ (N B ∗ + N B ) = 0.76 ± 0.08 ± 0.06 , where the first error is statistical and the second is systematic.

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Measurement of the inclusive production of neutral pions and charged particles on the Z0 resonance

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 259 (1991) 199-208, 1991.
Inspire Record 314407 DOI 10.17182/hepdata.29468

We present a study of the inclusive production of neutral pions and charged particles from 112 000 hadronic Z 0 decays. The measured inclusive momentum distributions can be reproduced by parton shower Monte Carlo programs and also by an analytical QCD calculation. Comparing our results to e + e − data between √ s = 9 and 91 GeV, we findfind that the evolution of the spectra with center of mass energy is consistent with the QCD predictions.

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Measurement of inclusive eta production in hadronic decays of the Z0

The L3 collaboration Adriani, O. ; Aguilar-Benitez, M. ; Ahlen, S. ; et al.
Phys.Lett.B 286 (1992) 403-412, 1992.
Inspire Record 336180 DOI 10.17182/hepdata.29161

We present a study of the inclusive η production based on 300 000 hadronic Z 0 decays. The measured inclusive momentum distribution can be reproduced by parton shower Monte Carlo programs and also by an analytical QCD calculation. Comparing our results with low energy e + e − data, we find that QCD describes both the shape and the energy evolution of the η spectrum. The comparison of η production rates in quark- and gluon-enriched jet samples does not show statistically significant evidence for more abundant production of η mesons in gluon fragmentation.

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Measurement of j / psi production in continuum e+ e- annihilations near s**(1/2) = 10.6-GeV

The BaBar collaboration Aubert, Bernard ; Boutigny, D. ; Gaillard, J.M. ; et al.
Phys.Rev.Lett. 87 (2001) 162002, 2001.
Inspire Record 558091 DOI 10.17182/hepdata.19450

The production of $J/\psi$ mesons in continuum $e^+e^-$ annihilations has been studied with the BABAR detector at energies near the $\Upsilon(4S)$ resonance, approximately 10.6 GeV. The mesons are distinguished from $J/\psi$ production in B decays through their center-of-mass momentum and energy. We measure the cross section $e^+e^-\to J/\psi X$ to be $2.52\pm 0.21\pm 0.21$ pb: for momentum above 2 GeV/c, it is $1.87\pm 0.10\pm 0.15$ pb. We set a 90% confidence level upper limit on the branching fraction for direct $\Upsilon(4S)$\to J/\psi X$ decays at $4.7\times 10^{-4}$.

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The e+ e- ---> pi+ pi- pi+ pi-, K+ K- pi+ pi-, and K+ K- K+ K- cross sections at center-of-mass energies 0.5-GeV to 4.5-GeV measured with initial-state radiation

The BaBar collaboration Aubert, Bernard ; Barate, R. ; Boutigny, D. ; et al.
Phys.Rev.D 71 (2005) 052001, 2005.
Inspire Record 676691 DOI 10.17182/hepdata.22111

We study the process $e^+e^-\to\pi^+\pi^-\pi^+\pi^-\gamma$, with a hard photon radiated from the initial state. About 60,000 fully reconstructed events have been selected from 89 $fb^{-1}$ of BaBar data. The invariant mass of the hadronic final state defines the effective \epem center-of-mass energy, so that these data can be compared with the corresponding direct $e^+e^-$ measurements. From the $4\pi$-mass spectrum, the cross section for the process $e^+e^-\to\pi^+\pi^-\pi^+\pi^-$ is measured for center-of-mass energies from 0.6 to 4.5 $GeV/c^2$. The uncertainty in the cross section measurement is typically 5%. We also measure the cross sections for the final states $K^+ K^- \pi^+\pi^-$ and $K^+ K^- K^+ K^-$. We observe the $J/\psi$ in all three final states and measure the corresponding branching fractions. We search for X(3872) in $J/\psi (\to\mu^+\mu^-) \pi^+\pi^-$ and obtain an upper limit on the product of the $e^+e^-$ width of the X(3872) and the branching fraction for $X(3872) \to J/\psi\pi^+\pi^-$.

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Study of e+ e- ---> pi+ pi- pi0 process using initial state radiation with BABAR

The BaBar collaboration Aubert, Bernard ; Barate, R. ; Boutigny, D. ; et al.
Phys.Rev.D 70 (2004) 072004, 2004.
Inspire Record 656680 DOI 10.17182/hepdata.41884

The process e+e- --> pi+ pi- pi0 gamma has been studied at a center-of-mass energy near the Y(4S) resonance using a 89.3 fb-1 data sample collected with the BaBar detector at the PEP-II collider. From the measured 3pi mass spectrum we have obtained the products of branching fractions for the omega and phi mesons, B(omega --> e+e-)B(omega --> 3pi)=(6.70 +/- 0.06 +/- 0.27)10-5 and B(phi --> e+e-)B(phi --> 3pi)=(4.30 +/- 0.08 +/- 0.21)10-5, and evaluated the e+e- --> pi+ pi- pi0 cross section for the e+e- center-of-mass energy range 1.05 to 3.00 GeV. About 900 e+e- --> J/psi gamma --> pi+ pi- pi0 gamma events have been selected and the branching fraction B(J/psi --> pi+ pi- pi0)=(2.18 +/- 0.19)% has been measured.

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Measurement of inclusive omega and eta' production in hadronic Z decays.

The L3 collaboration Acciarri, M. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 393 (1997) 465-476, 1997.
Inspire Record 427107 DOI 10.17182/hepdata.47618

We present a study of the inclusive ω and η′ production based on 3.1 million hadronic Z decays recorded with the L3 detector at LEP during 1991–1994. The production rates per hadronic Z decay have been measured to be 1.17±0.17 ω mesons and 0.25±0.04 η′ mesons. The production rates and the differential cross sections have been compared with predictions of the JETSET and the HERWIG Monte Carlo models. We have observed that the differential cross sections can be described by an analytical quantum chromodynamics calculation.

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Measurement of the tau polarisation at LEP.

The ALEPH collaboration Heister, A. ; Schael, S. ; Barate, R. ; et al.
Eur.Phys.J.C 20 (2001) 401-430, 2001.
Inspire Record 555653 DOI 10.17182/hepdata.49751

The polarisation of $\tau$'s produced in Z decay is measured using 160 pb$^{-1}$ of data accumulated at LEP by the ALEPH detector between 1990 and 1995. The variation of the polarisation with polar angle yields the two parameters ${\cal A}_e = 0.1504 \pm 0.0068 $ and ${\cal A}_{\tau} = 0.1451 \pm 0.0059$ which are consistent with the hypothesis of $e$-$\tau$ universality. Assuming universality, the value ${\cal A}_{e{-}\tau} = 0.1474 \pm 0.0045$ is obtained from which the effective weak mixing angle $\sin^2 {\theta_{\mathrm{W}}^{\mathrm{eff}}} =0.23147 \pm 0.00057 $ is derived.

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Exclusive production of pion and kaon meson pairs in two photon collisions at LEP.

The ALEPH collaboration Heister, A. ; Schael, S. ; Barate, R. ; et al.
Phys.Lett.B 569 (2003) 140-150, 2003.
Inspire Record 626022 DOI 10.17182/hepdata.49730

Exclusive production of π and K meson pairs in two photon collisions is measured with ALEPH data collected between 1992 and 2000. Cross-sections are presented as a function of cos θ ∗ and invariant mass, for | cos θ ∗ |<0.6 and invariant masses between 2.0 and 6.0 GeV/ c 2 (2.25 and 4.0 GeV/ c 2 ) for pions (kaons). The shape of the distributions are found to be well described by QCD predictions but the data have a significantly higher normalization.

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Inclusive Sigma- and Lambda(1520) production in hadronic Z decays.

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Phys.Lett.B 475 (2000) 429-447, 2000.
Inspire Record 524694 DOI 10.17182/hepdata.49984

Production of Sigma- and Lambda(1520) in hadronic Z decays has been measured using the DELPHI detector at LEP. The Sigma- is directly reconstructed as a charged track in the DELPHI microvertex detector and is identified by its Sigma -> n pi decay leading to a kink between the Sigma- and pi-track. The reconstruction of the Lambda(1520) resonance relies strongly on the particle identification capabilities of the barrel Ring Imaging Cherenkov detector and on the ionisation loss measurement of the TPC. Inclusive production spectra are measured for both particles. The production rates are measured to be <N_{Sigma-}/N_{Z}^{had}> = 0.081 +/- 0.002 +/- 0.010, <N_{Lambda(1520)}/N_{Z}^{had}> = 0.029 +/- 0.005 +/- 0.005. The production rate of the Lambda(1520) suggests that a large fraction of the stable baryons descend from orbitally excited baryonic states. It is shown that the baryon production rates in Z decays follow a universal phenomenological law related to isospin, strangeness and mass of the particles.

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Measurement of K^+K^- production in two-photon collisions in the resonant-mass region

The Belle collaboration Abe, Kazuo ; Abe, Koya ; Abe, T. ; et al.
Eur.Phys.J.C 32 (2003) 323-336, 2003.
Inspire Record 629334 DOI 10.17182/hepdata.50324

K^+K^- production in two-photon collisions has been studied using a large data sample of 67 fb^{-1} accumulated with the Belle detector at the KEKB asymmetric e^+e^- collider. We have measured the cross section for the process gamma gamma -> K^+ K^- for center-of-mass energies between 1.4 and 2.4 GeV, and found three new resonant structures in the energy region between 1.6 and 2.4 GeV. The angular differential cross sections have also been measured.

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Study of the process e+e- -> omega pi0 in the phi-meson mass region with the KLOE detector

The KLOE collaboration Ambrosino, F. ; Antonelli, A. ; Antonelli, M. ; et al.
Phys.Lett.B 669 (2008) 223-228, 2008.
Inspire Record 791841 DOI 10.17182/hepdata.50498

We have studied the e+e- -> omegapi0 cross section in the sqrt(s) interval 1000-1030 MeV using the pi+pi-pi0pi0 and pi0pi0gamma final states with a sample of ~600 pb^-1 collected with the KLOE detector at DAFNE. By fitting the observed interference pattern around M_phi for both final states, we extract the ratio of the decay widths Gamma(omega->pi0gamma)/Gamma(omega->pi+pi-pi0) = 0.0897 +- 0.0016 and derive the branching fractions BR(omega -> pi+pi-pi0)= (90.24 +- 0.19)%, BR(omega -> pi0gamma) = (8.09 +- 0.14)%. The parameters describing the e+e- -> omegapi0 reaction around M_\phi are also used to extract the branching fraction for the OZI and G-parity violating phi -> omegapi0 decay: BR(phi->omegapi0) = (4.4 +- 0.6)x10^-5.

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Measurement of the Lepton Forward-Backward Asymmetry in Inclusive $B \rightarrow X_s \ell^+ \ell^-$ Decays

The Belle collaboration Sato, Y. ; Ishikawa, A. ; Yamamoto, H. ; et al.
Phys.Rev.D 93 (2016) 032008, 2016.
Inspire Record 1283183 DOI 10.17182/hepdata.64698

We report the first measurement of the lepton forward-backward asymmetry ${\cal A}_{\rm FB}$ as a function of the squared four-momentum of the dilepton system, $q^2$, for the electroweak penguin process $B \rightarrow X_s \ell^+ \ell^-$ with a sum of exclusive final states, where $\ell$ is an electron or a muon and $X_s$ is a hadronic recoil system with an $s$ quark. The results are based on a data sample containing $772\times10^6$ $B\bar{B}$ pairs recorded at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB $e^+ e^-$ collider. ${\cal A}_{\rm FB}$ for the inclusive $B \rightarrow X_s \ell^+ \ell^-$ is extrapolated from the sum of 10 exclusive $X_s$ states whose invariant mass is less than 2 GeV/$c^2$. For $q^2 > 10.2$ GeV$^2$/$c^2$, ${\cal A}_{\rm FB} < 0$ is excluded at the 2.3$\sigma$ level, where $\sigma$ is the standard deviation. For $q^2 < 4.3$ GeV$^2$/$c^2$, the result is within 1.8$\sigma$ of the Standard Model theoretical expectation.

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$\Lambda$ Production in $e^+ e^-$ Annihilations at 29-{GeV}: A Comparison With Lund Model Predictions

Baringer, Philip S. ; Abachi, S. ; Beltrami, I. ; et al.
Phys.Rev.Lett. 56 (1986) 1346, 1986.
Inspire Record 17781 DOI 10.17182/hepdata.20257

This paper presents measurements of the inclusive production cross sections of Λ baryons in e+e− annihilations at s=29 GeV. The data sample corresponds to an integrated luminosity of 256 pb−1 collected with the High-Resolution Spectrometer at the SLAC storage ring PEP. Comparisons are made to the predictions of the Lund model. The data are well described with use of a strange-diquark suppression parameter, (usud)(sd), of 0.89 ± 0.10−0.16+0.56, and the measured Λc→Λ+X branching ratio of (23 ± 10)%.

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A Measurement of the Direct Photon Spectrum From the $\Upsilon$ (1s)

The CLEO collaboration Csorna, S.E. ; Mestayer, M.D. ; Panvini, R.S. ; et al.
Phys.Rev.Lett. 56 (1986) 1222, 1986.
Inspire Record 220652 DOI 10.17182/hepdata.20260

We have observed decays of the ϒ(1S) into hadronic final states containing high-energy photons. These are interpreted as coming from the decay ϒ(1S)→γ+gluon+gluon. We compare the shape of the observed photon energy spectrum with several theoretical predictions and deduce the value of the strong-coupling constant αs and the QCD scale parameter ΛMS― (MS― denotes the modified minimal-subtraction scheme) associated with each prediction.

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Observation of Tensor and Scalar Mesons Produced in $e^+ e^-$ Annihilation at 29-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Rev.Lett. 57 (1986) 1990, 1986.
Inspire Record 18688 DOI 10.17182/hepdata.20227

The production of the tensor mesons f0(1270) and K*0(1430) and the scalar meson S(975) has been observed in e+e− annihilation at 29 GeV center-of-mass energy by use of data obtained with the high-resolution spectrometer at the SLAC e+e− storage ring PEP. The mean multiplicities for meson momenta greater than 1450 MeV/c are 〈nf0〉=0.11±0.04, 〈nK*0(1430)〉=0.10±0.06, and 〈nS〉=0.05±0.02 per hadronic event. The fragmentation functions of the tensor mesons are in good agreement with the predictions of the Webber cluster model. The data are consistent with a predominant strange-quark content on the S meson.

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Production of $\phi$ and F (1970) $\to \phi \pi$ in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.Lett. 54 (1985) 2568, 1985.
Inspire Record 213242 DOI 10.17182/hepdata.20340

Data from the high-resolution spectrometer at PEP have been used to study the inclusive production of φ mesons and F± mesons decaying into φπ±. Fragmentation functions and cross sections are presented and compared to existing data. The total φ cross section at 29 GeV is 40±6 pb. The observed F signal in the region z>0.4, given the assumption that R(F)[R(F)+R(D)]=0.15, corresponds to an F→φπ branching ratio of (3.3±1.1)%. The measured F mass is 1963±3±3 MeV/c2.

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Measurement of alpha-s (M(Z)**2) from hadronic event observables at the Z0 resonance

The SLD collaboration Abe, K. ; Abt, I. ; Ahn, C.J. ; et al.
Phys.Rev.D 51 (1995) 962-984, 1995.
Inspire Record 378545 DOI 10.17182/hepdata.22450

The strong coupling alpha_s(M_Z^2) has been measured using hadronic decays of Z^0 bosons collected by the SLD experiment at SLAC. The data were compared with QCD predictions both at fixed order, O(alpha_s^2), and including resummed analytic formulae based on the next-to-leading logarithm approximation. In this comprehensive analysis we studied event shapes, jet rates, particle correlations, and angular energy flow, and checked the consistency between alpha_s(M_Z^2) values extracted from these different measures. Combining all results we obtain alpha_s(M_Z^2) = 0.1200 \pm 0.0025(exp.) \pm 0.0078(theor.), where the dominant uncertainty is from uncalculated higher order contributions.

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Study of inclusive Lambda production in e+ e- annihilations at 29-GeV

The HRS collaboration Geld, T.L. ; Neal, H. ; Akerlof, C. ; et al.
Phys.Rev.D 45 (1992) 3949-3954, 1992.
Inspire Record 339573 DOI 10.17182/hepdata.22726

Cross sections are presented for the inclusive production of Λ hyperons in electron-positron annihilations at s=29 GeV based on the full 291-pb−1 sample of data taken in the High Resolution Spectrometer experiment at the SLAC e+e− storage ring PEP. These results, and the associated correlation analyses, are consistent with the Lund model predictions with the strange diquark suppression ratio δ fixed at 0.59±0.10±0.18, as compared to the standard Lund value of 0.32. The Λ multiplicity has been found to be 0.182±0.020 per event. The opposite-strangeness multiplicity 〈nΛΛ¯〉 has been measured to be 0.046±0.020, whereas the like-strangeness multiplicity 〈nΛΛ+Λ¯Λ¯〉 is 0.009±0.028. A strong correlation is found between Λ's and Λ¯'s; when one is found in an event, the other is found in the same event with a probability that exceeds 50%.

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Observation of $\psi(4415)\to D \bar D{}^{*}_2(2460)$ decay using initial-state radiation

The Belle collaboration Pakhlova, G. ; Adachi, I. ; Aihara, H. ; et al.
Phys.Rev.Lett. 100 (2008) 062001, 2008.
Inspire Record 759073 DOI 10.17182/hepdata.21846

We report the first observation of the $\psi(4415)$ resonance in the reaction $\e^+e^-\to D^0 D^-\pi^+$ and a measurement of its cross section in the center-of-mass energy range $4.0\mathrm{GeV}$ to $5.0\mathrm{GeV}$ with initial state radiation. From a study of resonant structure in $\psi(4415)$ decay we conclude that the $\psi(4415)\to D^0 D^-\pi^+$ decay is dominated by $\psi(4415)\to D \bar D{}^{*}_2(2460)$. We obtain $\mathcal{B}(\psi(4415)\to D^0 D^-\pi^+_{\mathrm {non-resonant}})/\mathcal{B}(\psi(4415)\to D \bar D{}^{*}_2(2460)\to D^0 D^-\pi^+)<0.22$ at 90% C.L. The analysis is based on a data sample collected with the Belle detector with an integrated luminosity of 673 $\mathrm{fb}^{-1}$.

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Observation of a near-threshold enhancement in the $e^+e^- \to \Lambda_c^+ \Lambda_c^-$ cross section using initial-state radiation

The Belle collaboration Pakhlova, G. ; Adachi, I. ; Aihara, H. ; et al.
Phys.Rev.Lett. 101 (2008) 172001, 2008.
Inspire Record 791660 DOI 10.17182/hepdata.21861

We report a measurement of the exclusive \$e^+e^- \to \Lambda_c^+ \Lambda_c^-$ cross section as a function of center-of-mass energy near the $\Lambda_c^+ \Lambda_c^-$ threshold. A clear peak with a significance of $8.8\sigma$ is observed in the $\Lambda_c^+ \Lambda_c^-$ invariant mass distribution just above threshold. With an assumption of a resonance origin for the observed peak, a mass and width of $M=(4634^{+8}_{-7} \mathrm{(stat.)} ^{+5}_{-8} \mathrm{(sys.)})\mevc$ and $\Gamma_{\mathrm{tot}}=(92^{+40}_{-24} \mathrm{(stat.)}^{+10}_{-21} \mathrm{(sys.)})\mev$ are determined. The analysis is based on a study of events with initial-state-radiation photons in a data sample collected with the Belle detector at the $\Upsilon(4S)$ resonance and nearby continuum with an integrated luminosity of 695 $\mathrm{fb}^{-1}$ at the KEKB asymmetric-energy $e^+e^_$ collider.

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Measurement of the near-threshold $e^+e^- \to D \bar D$ cross section using initial-state radiation

The Belle collaboration Pakhlova, G. ; Adachi, I. ; Aihara, H. ; et al.
Phys.Rev.D 77 (2008) 011103, 2008.
Inspire Record 757220 DOI 10.17182/hepdata.22082

We report measurements of the exclusive cross section for $e^+e^- \to D \overline D $, where $D=D^0$ or $D^+$, in the center-of-mass energy range from the $D \overline D $ threshold to $5\mathrm{GeV}/c^2$ with initial-state radiation. The analysis is based on a data sample collected with the Belle detector with an integrated luminosity of $673$ $\mathrm{fb}^{-1}$.

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Measurement of inclusive monmentum spectra and multiplicity distributions of charged particles at s**(1/2) approx. 2-GeV to 5-GeV.

The BES collaboration Dunwoodie, W. ; Bai, J.Z. ; Ban, Y. ; et al.
Phys.Rev.D 69 (2004) 072002, 2004.
Inspire Record 622224 DOI 10.17182/hepdata.22183

Inclusive momentum spectra and multiplicity distributions of charged particles measured with BESII detector at center of mass energies of 2.2,2.6,3.0,3.2,4.6 and 4.8 GeV are presented. Values of the second binomial moment, $R_2$, obtained from the multiplicity distributions are reported. These results are compared with both experimental data from high energy $e^+e^-$, $ep$ and $p\bar{p}$ experiments and QCD calculations.

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Measurements of charm fragmentation into D/s*+ and D/s+ in e+ e- annihilations at s**(1/2) = 10.5-GeV.

The CLEO collaboration Briere, Roy A. ; Behrens, B.H. ; Ford, William T. ; et al.
Phys.Rev.D 62 (2000) 072003, 2000.
Inspire Record 526554 DOI 10.17182/hepdata.22227

A study of charm fragmentation into $D_s^{*+}$ and $D_s^+$ in $e^+e^-$ annihilations at $\sqrt{s}$=10.5 GeV is presented. This study using $4.72 \pm 0.05$ fb$^{-1}$ of CLEO II data reports measurements of the cross-sections $\sigma(D_s^{*+})$ and $\sigma(D_s^+)$ in momentum regions above $x=0.44$, where $x$ is the $D_s$ momentum divided by the maximum kinematically allowed $D_s$ momentum. The $D_s$ vector to vector plus pseudoscalar production ratio is measured to be $P_V(x(D_s^+)>0.44)=0.44\pm0.04$

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Updated cross section measurement of $e^+ e^- \to K^+ K^- J/\psi$ and $K_S^0K_S^0J/\psi$ via initial state radiation at Belle

The Belle collaboration Shen, C.P. ; Yuan, C.Z. ; Wang, P. ; et al.
Phys.Rev.D 89 (2014) 072015, 2014.
Inspire Record 1282602 DOI 10.17182/hepdata.64381

The cross sections of the processes $e^+ e^- \to K^+ K^- J/\psi$ and $K_S^0K_S^0J/\psi$ are measured via initial state radiation at center-of-mass energies between the threshold and 6.0~GeV using a data sample of 980~fb$^{-1}$ collected with the Belle detector on or near the $\Upsilon(nS)$ resonances, where $n=$1, 2, ..., 5. The cross sections for $e^+ e^- \to K^+ K^- J/\psi$ are at a few pb level and the average cross section for $e^+ e^- \to K_S^0K_S^0J/\psi$ is $1.8\pm 0.6 (\rm stat.)\pm 0.3 (\rm syst.)$~pb between 4.4 and 5.2~GeV. All of them are consistent with previously published results with improved precision. A search for resonant structures and associated intermediate states in the cross section of the process $e^+ e^- \to K^+ K^- J/\psi$ is performed.

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Study of Anti-deuteron Production in $e^+ e^-$ Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Glaser, R. ; Harder, G. ; et al.
Phys.Lett.B 236 (1990) 102-108, 1990.
Inspire Record 283027 DOI 10.17182/hepdata.29735

We report a measurement of the production of antideuterons d in e + e − annihilation at centre-of-mass energies around 10 GeV using the ARGUS detector at the DORIS II storage ring. We observe an enhancement of d production in direct hadronic ϒ (1S) and ϒ (2S) resonance decays. From 21 events width a d candidate the inclusive cross section 1 σ dir had · d σ d p and the production rate of antideuterons are determined. A production rate of (6.0±2.0±0.6) × 10 -5 d per direct hadronic ϒ decay and a 90% CL upper limit of 1.7 × 10 −5 d per e + e − →q q continuum event are obtained. These results are related to antiproton production through a simple model.

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Observation of $\Delta^{++}$ (1232) Production in $e^+ e^-$ Annihilations Around 10-{GeV}

The ARGUS collaboration Albrecht, H. ; Glaser, R. ; Harder, G. ; et al.
Phys.Lett.B 230 (1989) 169-174, 1989.
Inspire Record 278932 DOI 10.17182/hepdata.29767

We report on the first observation of Δ(1232) ++ and Δ(1232)++¯ baryons in e + e − annihilation at energies around 10 GeV, using the ARGUS detector at DORIS II. The sum of the rates of Δ ++ and Δ++¯ per hadronic event in the continuum is measured to be 0.040±0.008±0.006, and the rate in direct ϒ(1S) decays is 0.124±0.016±0.015. The momentum spectrum of Δ ++ baryons in direct ϒ(1S) decays has been measured.

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Observation of the D*0 (2459) in e+ e- Annihilation

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 221 (1989) 422-426, 1989.
Inspire Record 268577 DOI 10.17182/hepdata.29827

Using the ARGUS detector at the DORIS II storage ring at DESY, we have observed a charmed meson of mass (2455±3±5) MeV/c2, decaying to D + π − . The natural width of this state is determined to be (15 +13+5 −10−10 ) MeV c 2 . The fragmentation function is hard, as expected for a leading charmed particle from nonresonant e + e − annihilation. Analysis of the decay angular distribution supports the hypothesis that the observed state is an L =1 excited charmed meson with spin-parity 2 + .

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Measurement of R and Search for New Quark Flavors Decaying Into Multi - Jet Final States in $e^+ e^-$ Collisions Between 54-{GeV} and 61.4-{GeV} c.m. Energies

The VENUS collaboration Abe, K. ; Amako, K. ; Arai, Y. ; et al.
Phys.Lett.B 234 (1990) 382-388, 1990.
Inspire Record 283774 DOI 10.17182/hepdata.29755

We accumulated e + e − annihilations into multi-hadrons at CM energies between 54.0 and 61.4 GeV with the VENUS detector at TRISTAN. Measured R -ratios are consistent with the standard model using the Z-boson mass; 91.1 GeV/ c 2 . Using two new observables, we searched for a planar four-jet and other multi-jet events resulting from the decay of a charge — 1 3 e b ' quark. Having observed no positive signals, we excluded b' masses between 19.4 and 28.2 GeV/ c 2 with a 95% confidence level, regardless of branching into charged current and loop-induced flavor-changing neutral current decay, including a possible Higgs decay process. The charge + 2 3 e top quark was excluded below f30.2 GeV/ c 2 .

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The Pion Electromagnetic Form-factor in the Timelike Energy Range 1.35-{GeV} $\le \sqrt{s} \le$ 2.4-{GeV}

The DM2 collaboration Bisello, D. ; Busetto, G. ; Castro, A. ; et al.
Phys.Lett.B 220 (1989) 321-327, 1989.
Inspire Record 267118 DOI 10.17182/hepdata.29829

The e + e − → π + π − cross section has been measured from about 280 events (an order of magnitude more than the previous world statistics) in the energy interval 1.35 ⩽ s ⩽ 2.4 GeV with the DM2 detector at DCI. The pion squared form factor | F π | 2 shows a deep minimum around 1.6 GeV/ c 2 and is better fit under the hypothesis of two ϱ-like resonance ⋍0.25 GeV/ c 2 wide with 1.42 and 1.77 GeV/ c 2 masses.

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Measurements of $\alpha^- s$ in $e^+ e^-$ Annihilation at $\sqrt{s}=53$.3-{GeV} and 59.5-{GeV}

The TOPAZ collaboration Adachi, I. ; Aihara, H. ; Doser, M. ; et al.
Phys.Lett.B 227 (1989) 495-500, 1989.
Inspire Record 279575 DOI 10.17182/hepdata.29800

We studied the energy-energy correlation (EEC) and its asymmetry (AEEC) using e + e − hadronic annihilation events obtained at √ s =53.3 GeV and 59.5 GeV with the TOPAZ detector at the TRISTAN collider. We used a Monte Carlo simulation combined with the QCD matrix elements by Gottschalk and Shatz and the Lund string fragmentation model. By comparing the experimental data with simulated events, we determined the strong coupling constant α s at both energies. The results are 0.129±0.007 (stat) ±0.010 (syst) at √ s =53.3 GeV and 0.122±0.008 (stat) ±0.010 (syst) at 59.5 GeV.

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Charged $D^*$ Production in $e^+ e^-$ Annihilation

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Phys.Lett.B 146 (1984) 121-125, 1984.
Inspire Record 202785 DOI 10.17182/hepdata.30496

None

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Inclusive Production of Vector Mesons $\rho^0$ and $K^{*\pm}$ in $e^+ e^-$ Annihilation at $\left<\sqrt{s}\right> = 35$-{GeV}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Phys.Lett.B 145 (1984) 441-447, 1984.
Inspire Record 203145 DOI 10.17182/hepdata.30510

None

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Search for New Heavy Quarks in $e^+ e^-$ Collisions Up to 46.78-{GeV} Center-of-mass Energy

The CELLO collaboration Behrend, H.J. ; Burger, J. ; Criegee, L. ; et al.
Phys.Lett.B 144 (1984) 297-301, 1984.
Inspire Record 202783 DOI 10.17182/hepdata.30514

The total e + e − annihilation onto hadron has been measured at CM energies between 33.00 and 36.72 GeV and between 38.66 and 46.78 GeV in steps of 20 and 30 MeV respectively. The average of the ratio R = σ ( e + e − → hadrons )/ σ is 〈 R 〉=3.85±0.12 and 〈 R 〉=4.04±0.10 for the two energy ranges. The systematic error on 〈 R 〉 is 0.31. Both values are consistent with the expectation for the known coloured quarks u, d, s, c and b. No evidence was found for the production of new quarks. If the largest fluctuation in R is interpreted as a narrow resonance, it corresponds to a product of the electronic width and the hadronic branching ratio Γ ee B had >2.9 keV at the 95% confidence level, well below the value expected for the toponium vector ground state with charge 2 3 e . The observed number of aplanar final states rules out the continuum production of a a new heavy flavour with pointlike cross section up to a CM energy of 45.4 GeV for a quarck charge of 1 3 e . and up to 46.6 GeV for 2 3 e at the 95% confidence level.

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Observation of F Meson Production in High-energy $e^+ e^-$ Annihilation

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Phys.Lett.B 136 (1984) 130-134, 1984.
Inspire Record 194774 DOI 10.17182/hepdata.30586

Production of the F meson by e + e − annihilation at high energies has been obsrved in the ϕπ final state with a mass of 1.975 ± 0.009 ± 0.010 GeV and a width consistent with the mass resolution. The yield of F production times branching ratio relative to μ pair production is R F ( x ⩾ 0.3) B (F ± → ϕπ ± ) = 0.061 ± 0.012 ± 0.018.

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Charged Pion, Kaon and Nucleon Production by e+ e- Annihilation for C.M. Energies Between 3.6-GeV and 5.2-GeV

The DASP collaboration Brandelik, R. ; Braunschweig, W. ; Martyn, H.U. ; et al.
Nucl.Phys.B 148 (1979) 189-227, 1979.
Inspire Record 132045 DOI 10.17182/hepdata.34826

Inclusive production of ifπ ± , K ± and p has been studied near charm threshold for c.m. energies between 3.6 and 5.2 GeV. Differential and scaling cross sections together with particle multiplicities have been determinated. By comparing data below and above charm threshold the charm contribution to if π ± and K ± production has been extracted. A comparison has been made between inclusice p production and inelastic electron-proton scattering. To study differences between three-gluon annihilation and two-quark production of the spectra from J/ decay and from non-resonant production at 3.6 GeV has been compared.

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Precision measurement of charged pion and kaon multiplicities in electron-positron annihilation at Q = 10.52 GeV

The Belle collaboration Leitgab, M. ; Seidl, R. ; Grosse Perdekamp, M. ; et al.
Phys.Rev.Lett. 111 (2013) 062002, 2013.
Inspire Record 1216515 DOI 10.17182/hepdata.62276

Measurements of inclusive differential cross sections for charged pion and kaon production in electron-positron annihilation have been carried out at a center-of-mass energy of Q = 10.52 GeV. The measurements were performed with the Belle detector at the KEKB electron-positron collider using a data sample containing 113 million e+e- -> qqbar events, where q={u,d,s,c}. We present charge-integrated differential cross sections d\sigma_h+-/dz for h+- = pi+-, K+- as a function of the relative hadron energy z = 2*E_h / sqrt{s} from 0.2 to 0.98. The combined statistical and systematic uncertainties for pi+- (K+-) are 4% (4%) at z ~ 0.6 and 15% (24%) at z ~ 0.9. The cross sections are the first measurements of the z-dependence of pion and kaon production for z > 0.7 as well as the first precision cross section measurements at a center-of-mass energy far below the Z^0 resonance used by the experiments at LEP and SLC.

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Study of $e^+ e^- \to \pi^+ \pi^- J/\psi$ and Observation of a Charged Charmonium-like State at Belle

The Belle collaboration Liu, Z.Q. ; Shen, C.P. ; Yuan, C.Z. ; et al.
Phys.Rev.Lett. 110 (2013) 252002, 2013.
Inspire Record 1225975 DOI 10.17182/hepdata.61431

The cross section for $e^+ e^- \to \pi^+ \pi^- J/\psi$ between 3.8 GeV and 5.5 GeV is measured with a 967 fb$^{-1}$ data sample collected by the Belle detector at or near the $\Upsilon(nS)$ ($n = 1,\ 2,\ ...,\ 5$) resonances. The Y(4260) state is observed, and its resonance parameters are determined. In addition, an excess of $\pi^+ \pi^- J/\psi$ production around 4 GeV is observed. This feature can be described by a Breit-Wigner parameterization with properties that are consistent with the Y(4008) state that was previously reported by Belle. In a study of $Y(4260) \to \pi^+ \pi^- J/\psi$ decays, a structure is observed in the $M(\pi^\pm\jpsi)$ mass spectrum with $5.2\sigma$ significance, with mass $M=(3894.5\pm 6.6\pm 4.5) {\rm MeV}/c^2$ and width $\Gamma=(63\pm 24\pm 26)$ MeV/$c^{2}$, where the errors are statistical and systematic, respectively. This structure can be interpreted as a new charged charmonium-like state.

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