Relating production and masses of the vector and P-wave mesons for light and heavy flavours al LEP

The production rates of primary vector and P-wave mesons in Z hadronic decays are analysed. The mass dependence of production rates for the bottom, charm, strange charm and three families of the light-flavour mesons is found to be very similar, allowing to relate the relative production rates for mesons with different flavours and, possibly, their masses. The strange axial mesons K_1(1273) and K_1(1402) might be assigned to the 1^+(1/2) and 1^+(3/2) levels degenerate with the 0^+(1/2) and 2^+(3/2) levels of the K^*_0(1430) and K^*_2(1430), respectively, if the observed K^*_0(1430) mass is replaced by its ``bare'' q\bar{q} mass corresponding to the K-matrix pole and close to the K_1(1273) mass. Then the 0^+(1/2) and 1^+(1/2) levels are below the 1^+(3/2) and 2^+(3/2) levels for the strange, charm and bottom mesons

Analysis of Cumulant Moments in High Energy Hadron-Hadron Collisions by Truncated Multiplicity Distributions

Oscillatory behavior of cumulant moments obtained from the experimental data in $pp$ collisions and $\bar{p}p$ collisions are analyzed by the modified negative binomial distribution (MNBD) and the negative binomial distribution (NBD). Both distributions well describe the cumulant moments obtained from the data. This fact shows sharp contrast to the result in $e^+e^-$ collisions, which is described by the the MNBD much better than by the NBD.Comment: 7 pages, Latex type, 7 figure

Charged rho meson production in neutrino-induced reactions at E_nu = 10 GeV

The neutrinoproduction of charged $\rho$ mesons on nuclei and nucleons is investigated for the first time at moderate energies ($\approx$ 10 GeV), using the date obtained with SKAT bubble chamber. No strong nuclear effects are observed in $\rho^+$ and $\rho^-$ production. The fractions of charged and neutral pions originating from $\rho$ decays are obtained and compared with higher energy data. From analysis of the obtained and available data on $\rho^+$ and $K^{*+}$(892) neutrinoproduction, the strangeness suppression factor in the quark string fragmentation is extracted: $\lambda_s = 0.18\pm0.03$. Estimations are obtained for cross sections of quasiexclusive single $\rho^+$ and coherent $\rho^+$ neutrinoproduction on nuclei. The estimated coherent cross section $\sigma_{\rho^+}^{coh}$ = (0.29$\pm0.16)\cdot 10^{-38}$ cm$^2$ is compatible with theoretical predictions.Comment: 7 pages, 6 figure

ρ(770)0\rho(770)^0, K∗(892)0^*(892)^0 and f0(980)_{0}(980) Production in Au-Au and pp Collisions at sNN\sqrt{s_{NN}} = 200 GeV

Preliminary results on $\rho(770)^0 \to \pi^{+}\pi^{-}$, K$^{*}(892)^{0} \to \pi$K and $f_{0}(980) \to \pi^{+}\pi^{-}$ production using the mixed-event technique are presented. The measurements are performed at mid-rapidity by the STAR detector in $\sqrt{s_{NN}}$= 200 GeV Au-Au and pp interactions at RHIC. The results are compared to different measurements at various energies.Comment: 4 pages, 6 figures. Talk presented at Quark Matter 2002, Nantes, France, July 18-24, 2002. To appear in the proceedings (Nucl. Phys. A

Multiplicity distributions at high energies as a sum of Poissonian-like distributions

It is shown that at collider energies experimental multiplicity distributions are well parameterized by a sum of Gupta-Sarma distributions. This extends earlier description of the lower energy data by the two parameter sum of Poissonians. Implications of the proposed parametrization for LHC are discussed.Comment: 16 pages, Latex, 4 EPS figure

Determination of ππ\pi\pi scattering lengths from measurement of π+π−\pi^+\pi^- atom lifetime

The DIRAC experiment at CERN has achieved a sizeable production of $\pi^+\pi^-$ atoms and has significantly improved the precision on its lifetime determination. From a sample of 21227 atomic pairs, a 4% measurement of the S-wave $\pi\pi$ scattering length difference $|a_0-a_2| = (.0.2533^{+0.0080}_{-0.0078}|_\mathrm{stat}.{}^{+0.0078}_{-0.0073}|_\mathrm{syst})M_{\pi^+}^{-1}$ has been attained, providing an important test of Chiral Perturbation Theory.Comment: 6 pages, 6 figure

First πK\pi K atom lifetime and πK\pi K scattering length measurements

The results of a search for hydrogen-like atoms consisting of $\pi^{\mp}K^{\pm}$ mesons are presented. Evidence for $\pi K$ atom production by 24 GeV/c protons from CERN PS interacting with a nickel target has been seen in terms of characteristic $\pi K$ pairs from their breakup in the same target ($178 \pm 49$) and from Coulomb final state interaction ($653 \pm 42$). Using these results the analysis yields a first value for the $\pi K$ atom lifetime of $\tau=(2.5_{-1.8}^{+3.0})$ fs and a first model-independent measurement of the S-wave isospin-odd $\pi K$ scattering length $\left|a_0^-\right|=\frac{1}{3}\left|a_{1/2}-a_{3/2}\right|= \left(0.11_{-0.04}^{+0.09} \right)M_{\pi}^{-1}$ ($a_I$ for isospin $I$).Comment: 14 pages, 8 figure

Leading particle effect, inelasticity and the connection between average multiplicities in {\bf e+e−e^+e^-} and {\bf pppp} processes

The Regge-Mueller formalism is used to describe the inclusive spectrum of the proton in $p p$ collisions. From such a description the energy dependences of both average inelasticity and leading proton multiplicity are calculated. These quantities are then used to establish the connection between the average charged particle multiplicities measured in {\bf $e^+e^-$} and {\bf $pp/{\bar p}p$} processes. The description obtained for the leading proton cross section implies that Feynman scaling is strongly violated only at the extreme values of $x_F$, that is at the central region ($x_F \approx 0$) and at the diffraction region ($x_F \approx 1$), while it is approximately observed in the intermediate region of the spectrum.Comment: 20 pages, 10 figures, to be published in Physical Review

The yields of light meson resonances in neutrinonuclear interactions at <E_nu> = 10 GeV

The total yields of the all well-established light mesonic resonances (up to the $\phi$(1020) meson) are estimated in neutrinonuclear interactions at < E_nu > = 10 GeV, using the data obtained with SKAT bubble chamber. For some resonances, the yields in the forward and backward hemispheres in the hadronic c.m.s. are also extracted. From the comparison of the obtained and available higher-energy data, an indication is obtained that the resonance yields rise almost linearly as a function of the mean mass of the neutrinoproduced hadronic system. The fractions of pions originating from the light resonance decays are inferred.Comment: 15 pages, 7 figure