Proposing "b-Parity" - a New Approximate Quantum Number in Inclusive b-jet Production - as an Efficient Probe of New Flavor Physics

We consider the inclusive reaction \ell^+ \ell^- -> nb +X (n = number of b-jets) in lepton colliders for which we propose a useful approximately conserved quantum number b_P=(-1)^n that we call b-Parity (b_P). We make the observation that the Standard Model (SM) is essentially b_P-even since SM b_P-violating signals are necessarily CKM suppressed. In contrast new flavor physics can produce b_P=-1 signals whose only significant SM background is due to b-jet misidentification. Thus, we show that b-jet counting, which relies primarily on b-tagging, becomes a very simple and sensitive probe of new flavor physics (i.e., of b_P-violation).Comment: 5 pages using revtex, 2 figures embadded in the text using epsfig. As will appear in Phys.Rev.Lett.. Considerable improvement was made in the background calculation as compared to version 1, by including purity parameters, QCD effects and 4-jets processe

Production and decay of the neutral top-pion in high energy e+e−e^{+}e^{-} colliders

We study the production and decay of the neutral top-pion $\pi_{t}^{0}$ predicted by topcolor-assisted technicolor(TC2) theory. Our results show that, except the dominant decay modes $b\bar{b}$, $\bar{t}c$ and $gg$, the $\pi_{t}^{0}$ can also decay into $\gamma\gamma$ and $Z \gamma$ modes. It can be significantly produced at high energy $e^{+}e^{-}$ collider(LC) experiments via the processes $e^{+}e^{-}\to \pi_{t}^{0}\gamma$ and $e^{+}e^{-}\to Z\pi_{t}^{0}$. We further calculate the production cross sections of the processes $e^{+}e^{-}\to\gamma\pi_{t}^{0}\to\gamma\bar{t}c$ and $e^{+}e^{-}\to Z\pi_{t}^{0}\to Z\bar{t}c$. We find that the signatures of the neutral top-pion $\pi_{t}^{0}$ can be detected via these processes.Comment: Latex file, 13 Pages, 6 eps figures. to be published in Phys.Rev.

CP Nonconservation in ppˉ→tbˉXp\bar p\to t\bar b X at the Tevatron

The reaction $p\bar p\to t\bar bX$ is found to be rather rich in exhibiting several different types of CP asymmetries. The spin of the top quark plays an important role. Asymmetries are related to form factors arising from radiative corrections of the $tbW$ production vertex due to non-standard physics. As illustrations, effects are studied in two Higgs Doublet Models and in Supersymmetric Models; asymmetries up to a few percent may be possible.Comment: 14 pages, 3 figures. Note: replaced due to minor problems that appeared on some postscript previewers. No change in conten

The quest for targeted delivery in colon cancer: mucoadhesive valdecoxib microspheres

The aim of the present study was to prepare valdecoxib, a cyclo-oxygenase-2 enzyme inhibitor, as a loaded multiparticulate system to achieve site-specific drug delivery to colorectal tumors. Film coating was done with the pH-sensitive polymer Eudragit S100 and sodium alginate was used as mucoadhesive polymer in the core. The microspheres were characterized by X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopy and were evaluated for particle size, drug load, in vitro drug release, release kinetics, accelerated stability, and extent of mucoadhesion. The coated microspheres released the drug at pH 7.4, the putative parameter for colonic delivery. When applied to the mucosal surface of freshly excised goat colon, microspheres pretreated with phosphate buffer pH 7.4 for 30 minutes showed mucoadhesion. To ascertain the effect of valdecoxib on the viability of Caco-2 cells, the 3-(4,5-dimethylthiazol-2yl) 2,5-diphenyltetrazolium bromide) test was conducted using both valdecoxib and coated microspheres. In both cases, the percentage of dehydrogenase activity indicated a lack of toxicity against Caco-2 cells in the tested concentration range. Drug transport studies of the drug as well as the coated microspheres in buffers of pH 6 and 7.4 across Caco-2 cell monolayers were conducted. The microspheres were found to exhibit slower and delayed drug release and lower intracellular concentration of valdecoxib

Automatic-dependent surveillance-broadcast experimental deployment using system wide information management

This paper describes an automatic-dependent surveillance-broadcast (ADS-B) implementation for air-to-air and ground-based experimental surveillance within a prototype of a fully automated air traffic management (ATM) system, under a trajectory-based-operations paradigm. The system is built using an air-inclusive implementation of system wide information management (SWIM). This work describes the relations between airborne and ground surveillance (SURGND), the prototype surveillance systems, and their algorithms. System's performance is analyzed with simulated and real data. Results show that the proposed ADS-B implementation can fulfill the most demanding surveillance accuracy requirements

Heavy quark polarizations of e+e−→qqˉhe^+e^-\to q \bar q h in the general two Higgs doublet model

The polarizations of the heavy quark ($q=t$ or $b$) in the process $e^+e^- \to q \bar q h$ have been calculated in the general two Higgs doublet model. The CP violating normal polarization of the top quark can reach 8%, and $2 \sim 3$ for the bottom quark, while it is zero in the standard model. The longitudinal and transverse polarizations of the bottom quark can be significantly different from those in SM and consequently could aslo be used as the probe of the new physics.Comment: 12 pages, discussion on statistic significance added, version to appear in PR

Tracking Target Signal Strengths on a Grid using Sparsity

Multi-target tracking is mainly challenged by the nonlinearity present in the measurement equation, and the difficulty in fast and accurate data association. To overcome these challenges, the present paper introduces a grid-based model in which the state captures target signal strengths on a known spatial grid (TSSG). This model leads to \emph{linear} state and measurement equations, which bypass data association and can afford state estimation via sparsity-aware Kalman filtering (KF). Leveraging the grid-induced sparsity of the novel model, two types of sparsity-cognizant TSSG-KF trackers are developed: one effects sparsity through $\ell_1$-norm regularization, and the other invokes sparsity as an extra measurement. Iterative extended KF and Gauss-Newton algorithms are developed for reduced-complexity tracking, along with accurate error covariance updates for assessing performance of the resultant sparsity-aware state estimators. Based on TSSG state estimates, more informative target position and track estimates can be obtained in a follow-up step, ensuring that track association and position estimation errors do not propagate back into TSSG state estimates. The novel TSSG trackers do not require knowing the number of targets or their signal strengths, and exhibit considerably lower complexity than the benchmark hidden Markov model filter, especially for a large number of targets. Numerical simulations demonstrate that sparsity-cognizant trackers enjoy improved root mean-square error performance at reduced complexity when compared to their sparsity-agnostic counterparts.Comment: Submitted to IEEE Trans. on Signal Processin

Measurement of XUV-absorption spectra of ZnS radiatively heated foils

Time-resolved absorption of zinc sulfide (ZnS) and aluminum in the XUV-range has been measured. Thin foils in conditions close to local thermodynamic equilibrium were heated by radiation from laser-irradiated gold spherical cavities. Analysis of the aluminum foil radiative hydrodynamic expansion, based on the detailed atomic calculations of its absorption spectra, showed that the cavity emitted flux that heated the absorption foils corresponds to a radiation temperature in the range 55 60 eV. Comparison of the ZnS absorption spectra with calculations based on a superconfiguration approach identified the presence of species Zn6+ - Zn8+ and S5+ - S6+. Based on the validation of the radiative source simulations, experimental spectra were then compared to calculations performed by post-processing the radiative hydrodynamic simulations of ZnS. Satisfying agreement is found when temperature gradients are accounted for

On the Stability and the Approximation of Branching Distribution Flows, with Applications to Nonlinear Multiple Target Filtering

We analyse the exponential stability properties of a class of measure-valued equations arising in nonlinear multi-target filtering problems. We also prove the uniform convergence properties w.r.t. the time parameter of a rather general class of stochastic filtering algorithms, including sequential Monte Carlo type models and mean eld particle interpretation models. We illustrate these results in the context of the Bernoulli and the Probability Hypothesis Density filter, yielding what seems to be the first results of this kind in this subject