Hydrodynamics of high gas-liquid ratio flows in a rotor-stator spinning disc reactor

The rotor-stator Spinning Disc Reactor (rs-SDR) is a versatile continuous flow reactor aiming at intensification of (micro)mixing and intensification of mass and heat transfer rates for both single and multiphase processes [e.g. 1,2]. For such transfer processes the hydrodynamics of the fluids govern the performance of the reactor. While for a single liquid flow the hydrodynamics in the rs-SDR are relatively well understood [3], for gas-liquid flows only low gas-liquid volumetric flow ratios (φv,G/φv,L≤1) have been described [2]. However, in many applications (such as boiling/condensing fluids, gas absorption) much higher gas-liquid flow ratios are encountered. To be able to perform (and more important, to control) such processes using a rs-SDR, the current work presents gas-liquid hydrodynamics (using high-speed image analysis), and the accompanying pressure drop, for high gas-liquid flow ratios (φv,G/φv,L = 120)

P33. Expression of alpha v beta 3 integrin in patients with high and low grade glioma

Fuente Fuente, Carlos;Puig-Pey, J.;Buenaño Pastor, Manue

DN interaction from meson exchange

A model of the DN interaction is presented which is developed in close analogy to the meson-exchange KbarN potential of the Juelich group utilizing SU(4) symmetry constraints. The main ingredients of the interaction are provided by vector meson (rho, omega) exchange and higher-order box diagrams involving D*N, D\Delta, and D*\Delta intermediate states. The coupling of DN to the pi-Lambda_c and pi-Sigma_c channels is taken into account. The interaction model generates the Lambda_c(2595) resonance dynamically as a DN quasi-bound state. Results for DN total and differential cross sections are presented and compared with predictions of an interaction model that is based on the leading-order Weinberg-Tomozawa term. Some features of the Lambda_c(2595) resonance are discussed and the role of the near-by pi-Sigma_c threshold is emphasized. Selected predictions of the orginal KbarN model are reported too. Specifically, it is pointed out that the model generates two poles in the partial wave corresponding to the Lambda(1405) resonance.Comment: 14 pages, 8 figure

First observation of the KS->pi0 gamma gamma decay

Using the NA48 detector at the CERN SPS, 31 KS->pi0 gamma gamma candidates with an estimated background of 13.7 +- 3.2 events have been observed. This first observation leads to a branching ratio of BR(KS->pi0 gamma gamma) = (4.9 +- 1.6(stat) +- 0.9(syst)) x 10^-8 in agreement with Chiral Perturbation theory predictions.Comment: 10 pages, 4 figures submitted to Phys. Lett.

Search for CP violation in K0 -> 3 pi0 decays

Using data taken during the year 2000 with the NA48 detector at the CERN SPS, a search for the CP violating decay K_S -> 3 pi0 has been performed. From a fit to the lifetime distribution of about 4.9 million reconstructed K0/K0bar -> 3 pi0 decays, the CP violating amplitude eta_000 = A(K_S -> 3 pi0)/A(K_L -> 3 pi0) has been found to be Re(eta_000) = -0.002 +- 0.011 +- 0.015 and Im(eta_000) = -0.003 +- 0.013 +- 0.017. This corresponds to an upper limit on the branching fraction of Br(K_S -> 3 pi0) < 7.4 x 10^-7 at 90% confidence level. The result is used to improve knowledge of Re(epsilon) and the CPT violating quantity Im(delta) via the Bell-Steinberger relation.Comment: 18 pages, 7 figures, submitted to Phys. Lett.

A precision measurement of direct CP violation in the decay of neutral kaons into two pions

The direct CP violation parameter Re(epsilon'/epsilon) has been measured from the decay rates of neutral kaons into two pions using the NA48 detector at the CERN SPS. The 2001 running period was devoted to collecting additional data under varied conditions compared to earlier years (1997-99). The new data yield the result: Re(epsilon'/epsilon) = (13.7 +/- 3.1) times 10^{-4}. Combining this result with that published from the 1997, 98 and 99 data, an overall value of Re(epsilon'/epsilon) = (14.7 +/- 2.2) times 10^{-4} is obtained from the NA48 experiment.Comment: 19 pages, 5 figures, to be published in Physics Letters

Measurement of the Ratio Gamma(KL -> pi+ pi-)/Gamma(KL -> pi e nu) and Extraction of the CP Violation Parameter |eta+-|

We present a measurement of the ratio of the decay rates Gamma(KL -> pi+ pi-)/Gamma(KL -> pi e nu), denoted as Gamma(K2pi)/Gamma(Ke3). The analysis is based on data taken during a dedicated run in 1999 by the NA48 experiment at the CERN SPS. Using a sample of 47000 K2pi and five million Ke3 decays, we find Gamma(K2pi)/Gamma(Ke3) = (4.835 +- 0.022(stat) +- 0.016(syst)) x 10^-3. From this we derive the branching ratio of the CP violating decay KL -> pi+ pi- and the CP violation parameter |eta+-|. Excluding the CP conserving direct photon emission component KL -> pi+ pi- gamma, we obtain the results BR(KL -> pi+ pi-) = (1.941 +- 0.019) x 10^-3 and |eta+-| = (2.223 +- 0.012) x 10^-3.Comment: 20 pages, 7 figures, accepted by Phys. Lett.

Measurement of K^0_e3 form factors

The semileptonic decay of the neutral K meson, KL -> pi e nu (Ke3), was used to study the strangeness-changing weak interaction of hadrons. A sample of 5.6 million reconstructed events recorded by the NA48 experiment was used to measure the Dalitz plot density. Admitting all possible Lorentz-covariant couplings, the form factors for vector (f_+(q^2)), scalar (f_S) and tensor (f_T) interactions were measured. The linear slope of the vector form factor lambda_+ = 0.0284+-0.0007+-0.0013 and values for the ratios |f_S/f_+(0)| = 0.015^{+0.007}_{-0.010}+-0.012 and |f_T/f_+(0)| = 0.05^{+0.03}_{-0.04}+-0.03 were obtained. The values for f_S and f_T are consistent with zero. Assuming only Vector-Axial vector couplings, lambda_+ = 0.0288+-0.0004+-0.0011 and a good fit consistent with pure V-A couplings were obtained. Alternatively, a fit to a dipole form factor yields a pole mass of M = 859+-18 MeV, consistent with the K^*(892) mass.Comment: 16 pages, 7 figures. submitted to Phys. Lett.