A Global Treatment Of VMD Physics Up To The ϕ\phi: I. e+e−e^+e^- Annihilations, Anomalies And Vector Meson Partial Widths

The HLS Model, equipped with a mechanism providing the breaking of U(3)/SU(3) symmetry and an isospin symmetry breaking leading naturally to vector meson mixing, has been recently shown to successfully account for e^+ e^- \ra \pi^+\pi^- cross section and for the dipion spectrum in $\tau$ decay. The present study shows that the full anomalous sector of the HLS model can be considered and is validated by the experimental data. Indeed, this extended model provides a successful simultaneous fit to the e^+ e^- \ra \pi^+\pi^- data together with the available data on e^+ e^- \ra \pi^0\gamma, e^+ e^- \ra \eta\gamma and e^+ e^- \ra \pi^0 \pi^+\pi^- cross sections. It is shown that the fit of these data sets also predicts an accurate description of the \eta/\eta^\prime \ra \pi^+ \pi^- \gamma decays fully consistent with the reported information on their branching fractions and spectra. Finally, one also derives from our global fits products of widths of the form \Gamma (V \ra f_1)\Gamma(V \ra e^+ e^-) and ratios of the form \Gamma (V \ra f_1)/\Gamma (V \ra f_2) describing decays of vector mesons to several non--leptonic final states.Comment: 58 pages, 10 figures Corrected a few misprints. Footnote 10 change

A Global Treatment Of VMD Physics Up To The ϕ\phi: I. e+e−e^+e^- Annihilations, Anomalies And Vector Meson Partial Widths

The HLS Model, equipped with a mechanism providing the breaking of U(3)/SU(3) symmetry and an isospin symmetry breaking leading naturally to vector meson mixing, has been recently shown to successfully account for e^+ e^- \ra \pi^+\pi^- cross section and for the dipion spectrum in $\tau$ decay. The present study shows that the full anomalous sector of the HLS model can be considered and is validated by the experimental data. Indeed, this extended model provides a successful simultaneous fit to the e^+ e^- \ra \pi^+\pi^- data together with the available data on e^+ e^- \ra \pi^0\gamma, e^+ e^- \ra \eta\gamma and e^+ e^- \ra \pi^0 \pi^+\pi^- cross sections. It is shown that the fit of these data sets also predicts an accurate description of the \eta/\eta^\prime \ra \pi^+ \pi^- \gamma decays fully consistent with the reported information on their branching fractions and spectra. Finally, one also derives from our global fits products of widths of the form \Gamma (V \ra f_1)\Gamma(V \ra e^+ e^-) and ratios of the form \Gamma (V \ra f_1)/\Gamma (V \ra f_2) describing decays of vector mesons to several non--leptonic final states.Comment: 58 pages, 10 figures Corrected a few misprints. Footnote 10 change

VMD, the WZW Lagrangian and ChPT: The Third Mixing Angle

We show that the Hidden Local Symmetry Model, supplemented with well-known procedures for breaking flavor SU(3) and nonet symmetry, provides all the information contained in the standard Chiral Perturbation Theory (ChPT) Lagrangian ${\cal L}^{(0)}+{\cal L}^{(1)}$. This allows to rely on radiative decays of light mesons ($VP\gamma$ and $P \gamma\gamma$) in order to extract some numerical information of relevance to ChPT: a value for $\Lambda_1=0.20 \pm 0.04$, a quark mass ratio of $\simeq 21.2 \pm 2.4$, and a negligible departure from the Gell-Mann--Okubo mass formula. The mixing angles are $\theta_8=-20.40^\circ \pm 0.96^\circ$ and $\theta_0=-0.05^\circ \pm 0.99^\circ$. We also give the values of all decay constants. It is shown that the common mixing pattern with one mixing angle $\theta_P$ is actually quite appropriate and algebraically related to the $\eta/\eta'$ mixing pattern presently preferred by the ChPT community. For instance the traditional $\theta_P$ is functionally related to the ChPT $\theta_8$ and fulfills $\theta_P \simeq \theta_8/2$. The vanishing of $\theta_0$, supported by all data on radiative decays, gives a novel relation between mixing angles and the violation of nonet symmetry in the pseudoscalar sector. Finally, it is shown that the interplay of nonet symmetry breaking through U(3) \ra SU(3)$\times$ U(1) satisfies all requirements of the physics of radiative decays without any need for additional glueballs.Comment: 31 pages, 1 figur

Multi-frame Packet Reservation Multiple Access Using Oscillation-scaled Histogram-based Markov Modelling of Video Codecs

A model is proposed for replacing the video codec in networking studies, which is tested for sources with a mean bitrate in the range of 10Kb/s to 10Mb/s. The standard frame sizes investigated are the International Telecommunications Union's (ITU) 352 x 288-pixel Common Intermediate Format (CIF), 176 x 144-pixel Quarter CIF (QCIF), 704 x 576-pixel 4CIF and 128 x 96-pixel Sub-QCIF (SQCIF). The proposed 20-state 'oscillation-scaled’ Markov model was found to represent the relevant video codec characteristics adequately. The performance of this model is then tested in the context of a novel Multi-frame Packet Reservation Multiple Access or MF-PRMA scheme, which is shown in Figure 17 to outperform conventional PRMA in terms of both its delay and packet dropping performance, reaching throughput values as high as 79%

A Global Treatment Of VMD Physics Up To The phi: II. tau Decay and Hadronic Contributions To g-2

Relying on the Hidden Local Symmetry (HLS) model equipped with a mechanism breaking the U(3)/SU(3)/SU(2) symmetries and generating a dynamical vector meson mixing, it has been shown that a global fit successfully describes the cross sections for the e+ e- -> pi+ pi-, e+ e- -> (pi0/eta) gamma and e+ e- -> pi0 pi+ pi- annihilation channels. One extends this global fit in order to include also the dipion spectra from the tau decay, taking into account all reported information on their statistical and systematic errors. A model accounting for lineshape distortions of the rho+- spectrum relative to rho0 is also examined when analyzing the tau data behavior within the global fit framework. One shows that a successful account for e+ e- annihilation data and tau spectra can be simultaneously reached. Then, issues related with non--perturbative hadronic contributions to the muon g-2 are examined in details. It is shown that all e+ e- data considered together allow for improved and motivated estimates for the a_mu(pi+ pi-), the pi+ pi- loop contribution to the muon g-2; for instance, integrated between 0.630 and 0.958 GeV, we find a_mu(pi+ pi-)= 359.62 +- 1.62 (in units of 10^{-10}), a 40% improvement of the current uncertainty. The effects of the various tau samples in the context of a global fit procedure leads to conclude that different lineshape distortions are revealed by the ALEPH, BELLE and CLEO data samples. Relying on global fits to the data quoted above, one also provides motivated estimates of the pi+ pi-, pi0 gamma, eta gamma and pi0 pi+ pi- contributions to a_mu up to 1 GeV with the smallest possible uncertainties. These estimates are based on various global fit configurations, each yielding a good probability.Comment: 43 pages, scope enlarged, model extended, same conclusions. Accepted for publication in EPJ-

The Pion Form Factor Within the Hidden Local Symmetry Model

We analyze a pion form factor formulation which fulfills the Analyticity requirement within the Hidden Local Symmetry (HLS) Model. We show that it implies an $s$--dependent dressing of the $\rho-\gamma$ VMD coupling and an account of several coupled channels. The corresponding function $F_\pi(s)$ provides nice fits of the pion form factor data from $s=-0.25$ to $s=1$ GeV$^2$. It is shown that the coupling to $K \bar{K}$ has little effects, while \omg \pi^0 improves significantly the fit quality below the $\phi$ mass. All parameters, except for the subtraction polynomial coefficients are fixed from the rest of the HLS phenomenology. The fits show consistency with the expected behaviour of $F_\pi(s)$ at $s=0$ up to ${\cal O} (s^2)$ and with the phase shift data on $\delta_1^1(s)$ from threshold to somewhat above the $\phi$ mass. The \omg sector is also examined in relation with recent data from CMD--2.We analyze a pion form factor formulation which fulfills the Analyticity requirement within the Hidden Local Symmetry (HLS) Model. We show that it implies an $s$--dependent dressing of the $\rho-\gamma$ VMD coupling and an account of several coupled channels. The corresponding function $F_\pi(s)$ provides nice fits of the pion form factor data from $s=-0.25$ to $s=1$ GeV$^2$. It is shown that the coupling to $K \bar{K}$ has little effects, while \omg \pi^0 improves significantly the fit quality below the $\phi$ mass. All parameters, except for the subtraction polynomial coefficients are fixed from the rest of the HLS phenomenology. The fits show consistency with the expected behaviour of $F_\pi(s)$ at $s=0$ up to ${\cal O} (s^2)$ and with the phase shift data on $\delta_1^1(s)$ from threshold to somewhat above the $\phi$ mass. The \omg sector is also examined in relation with recent data from CMD-2.We analyze a pion form factor formulation which fulfills the Analyticity requirement within the Hidden Local Symmetry (HLS) Model. We show that it implies an $s$--dependent dressing of the $\rho-\gamma$ VMD coupling and an account of several coupled channels. The corresponding function $F_\pi(s)$ provides nice fits of the pion form factor data from $s=-0.25$ to $s=1$ GeV$^2$. It is shown that the coupling to $K \bar{K}$ has little effects, while \omg \pi^0 improves significantly the fit quality below the $\phi$ mass. All parameters, except for the subtraction polynomial coefficients are fixed from the rest of the HLS phenomenology. The fits show consistency with the expected behaviour of $F_\pi(s)$ at $s=0$ up to ${\cal O} (s^2)$ and with the phase shift data on $\delta_1^1(s)$ from threshold to somewhat above the $\phi$ mass. The \omg sector is also examined in relation with recent data from CMD-2.We analyze a pion form factor formulation which fulfills the Analyticity requirement within the Hidden Local Symmetry (HLS) Model. We show that it implies an $s$--dependent dressing of the $\rho-\gamma$ VMD coupling and an account of several coupled channels. The corresponding function $F_\pi(s)$ provides nice fits of the pion form factor data from $s=-0.25$ to $s=1$ GeV$^2$. It is shown that the coupling to $K \bar{K}$ has little effects, while $\omega \pi^0$ improves significantly the fit quality below the $\phi$ mass. All parameters, except for the subtraction polynomial coefficients are fixed from the rest of the HLS phenomenology. The fits show consistency with the expected behaviour of $F_\pi(s)$ at $s=0$ up to ${\cal O} (s^2)$ and with the phase shift data on $\delta_1^1(s)$ from threshold to somewhat above the $\phi$ mass. The $\omega$ sector is also examined in relation with recent data from CMD-2

Rich Reconstruction and particle identification using ring fit methods: Standalone PID in the Rich2 detector

We have extended the ring fit algorithm presented in earlier works, in order to transform it into a fully standalone PID algorithm running over the full RICH2 momentum range. For this purpose, the full information provided by the tracking (track direction and momentum as well as their errors) is accounted for in the minimized chi squared function along with the photon information. Additionally, all available information concerning the Cerenkov light emission effect is accounted for in the PID algorithm. PID efficiencies and misidentification rates are found similar to the global ID results, while the statistical information is still much more reliable

DMSO removal reduces stem-cell infusion-related toxicity and allows excellent engraftment of cryopreserved unrelated cord blood and autologous stem cells

UNIFESP, GRAACC, Pediat Oncol Inst, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilUNIFESP, GRAACC, Pediat Oncol Inst, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilWeb of Scienc

Large volume leukapheresis for autologous peripheral blood stem cell collection in children weighting less than 25 kg

Universidade Federal de São Paulo, GRAACC, Pediat Oncol Inst, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pathol, São Paulo, BrazilUniversidade Federal de São Paulo, GRAACC, Pediat Oncol Inst, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pathol, São Paulo, BrazilWeb of Scienc

The Dipion Mass Spectrum In e+e- Annihilation and tau Decay: A Dynamical (rho0, omega, phi) Mixing Approach

We readdress the problem of finding a simultaneous description of the pion form factor data in e+e- annihilations and in tau decays. For this purpose, we work in the framework of the Hidden Local Symmetry (HLS) Lagrangian and modify the vector meson mass term by including the pion and kaon loop contributions. This leads us to define the physical rho, omega and phi fields as linear combinations of their ideal partners, with coefficients being meromorphic functions of s, the square of the 4--momentum flowing into the vector meson lines. This allows us to define a dynamical, i.e. s-dependent, vector meson mixing scheme. The model is overconstrained by extending the framework in order to include the description of all meson radiative (V P gamma and P gamma gamma couplings) and leptonic (Ve+e- couplings) decays and also the isospin breaking (omega/ phi --> pi+ pi-) decay modes. The model provides a simultaneous, consistent and good description of the e+e- and tau dipion spectra. The expression for pion form factor in the latter case is derived from those in the former case by switching off the isospin breaking effects specific to e+e- and switching on those for tau decays. Besides, the model also provides a good account of all decay modes of the form V P gamma, Pgamma gamma as well as the isospin breaking decay modes. It leads us to propose new reference values for the rho^0 --> e+ e- and omega --> pi+ pi- partial widths which are part of our description of the pion form factor. Other topics (phi --> K anti K, the rho meson mass and width parameters) are briefly discussed. Therefore, we confirm the 3.3 sigma discrepancy between the theoretical estimate of a_mu based on e+e- and its direct BNL measurement.Comment: 71 pages, 8 figures. Accepted by EPJ C. Version 3: correct minor typos, minor changes spread out into the text. Extension of Sections 12.2 and 12.3.5 and introduction of the new Appendix