Prospects for B(s)0→π0π0B^0_{(s)}\to\pi^0\pi^0 and B(s)0→ηηB^0_{(s)}\to\eta\eta modes and corresponding CPCP asymmetries at Tera-ZZ

The physics potential of measuring $B^0_{(s)}\to\pi^0\pi^0$ and $B^0_{(s)}\to\eta\eta$ decays via four-photon final states at Tera-$Z$ phase of CEPC or FCC-ee is investigated in this paper. We propose an electromagnetic calorimeter (ECAL) with both high energy resolution and excellent separation power to efficiently reconstruct $\pi^0$ and $\eta$ from hadronic final states with high photon multiplicity. The resulting $B$-meson mass resolution is approximately 30 MeV, allowing 3 $\sigma$ separation between $B^0$ and $B_s^0$. With the assistance of the $b$-jet tagging, the relative sensitivities to $B^0\to\pi^0\pi^0$, $B^0_s\to\pi^0\pi^0$, $B^0\to\eta\eta$, and $B^0_s\to\eta\eta$ signal strengths at Tera-$Z$ are projected as 0.45%, 4.5%, 18%, and 0.95%, respectively. Their dependence on various detector performances is also discussed. In addition, $B^0\to\pi^0\pi^0$ and its two isospin-related modes are paid special attention due to their roles in the determination of the CKM angle $\alpha$ ($\phi_2$). The anticipated precisions of their branching-ratio and $CP$-asymmetry measurements at Tera-$Z$ are evaluated. We show that the measurement of the time-integrated $B^0\to\pi^0\pi^0$ $CP$ asymmetry at Tera-$Z$ is complementary to $B$-factory ones. The precision on $\alpha$ combining $Z$- and $B$-factory results reaches $0.4^\circ$, lower than the systematic uncertainties attached to isospin breaking

Analysis of IUE observations of hydrogen in comets

The large body of hydrogen Lyman-alpha observations of cometary comae obtained with the International Ultraviolet Explorer satellite has gone generally unanalyzed because of two main modeling complications. First, the inner comae of many bright (gas productive) comets are often optically thick to solar Lyman-alpha radiation. Second, even in the case of a small comet (low gas production) the large IUE aperture is quite small as compared with the immense size of the hydrogen coma, so an accurate model which properly accounts for the spatial distribution of the coma is required to invert the inferred brightnesses to column densities and finally to H atom production rates. Our Monte Carlo particle trajectory model (MPTM), which for the first time provides the realistic full phase space distribution of H atoms throughout the coma was used as the basis for the analysis of IUE observations of the inner coma. The MCPTM includes the effects of the vectorial ejection of the H atoms upon dissociation of their parent species (H2O and OH) and of their partial collisional thermalization. Both of these effects are crucial to characterize the velocity distribution of the H atoms. A new spherical radiative transfer calculation based on our MCPTM was developed to analyze IUE observations of optically thick H comae. The models were applied to observations of comets P/Giacobini-Zinner and P/Halley

Low Mass Dimuon Production in p-A Collisions at 400 GeV/c with the NA60 Detector

The NA60 experiment has studied low-mass muon pair production in proton-nucleus collisions with a system of Be, Cu, In, W, Pb and U targets using a 400 GeV/c proton beam at the CERN SPS. The mass spectrum is well described by the superposition of the two-body and Dalitz decays of the light neutral mesons eta, rho, omega, eta' and phi. A new measurement of the electromagnetic transition form factors of the eta and omega was performed. The values found agree with the previous available measurements, improving their uncertainty thanks to the higher statistics, and confirm the discrepancy with the prediction of the Vector Meson Dominance (VMD) model in the case of the electromagnetic form factor of the omega meson; for this latter, the comparison of the data to an improved calculation including also a direct point-like term is discussed. The pT spectra for the omega and phi mesons are studied in the full pT range accessible, up to pT = 2 GeV/c. The pT spectrum of the eta meson is also considered, starting from pT = 0.6 GeV/c. The cross section ratios rho/omega, phi/omega and eta/omega have been studied as a function of the size A of the production target, and an increase of the eta and phi production with respect to the omega is observed from p-Be to p-U collisions. The nuclear dependence of the production cross sections of the eta, omega and phi mesons has been parameterized with the power law A^alpha, where the alpha parameter has been found to increase as a function of pT

Energy-Driven Pattern Formation in Planar Dipole-Dipole Systems

A variety of two-dimensional fluid systems, known as dipole-mediated systems, exhibit a dipole-dipole interaction between their fluid constituents. The com- petition of this repulsive dipolar force with the cohesive fluid forces cause these systems to form intricate and patterned structures in their boundaries. In this thesis, we show that the microscopic details of any such system are irrelevant in the macroscopic limit and contribute only to a constant offset in the system’s energy. A numeric model is developed, and some important stable domain morphologies are characterized. Previously unresolved bifurcating branches are explored. Finally, by applying a random energy background to the numer- ics, we recover the smörgåsbord of diverse domain morphologies that are seen in experiment. We develop an empirical description of these domains and use it to demonstrate that the system\u27s nondimensional parameter, which is the ratio of the line tension to the dipole–dipole density, can be extracted for any domain using only its shape

Recurrent deletions of ULK4 in schizophrenia : a gene crucial for neuritogenesis and neuronal motility

Peer reviewedPublisher PD

Lattice QCD at the end of 2003

I review recent developments in lattice QCD. I first give an overview of its formalism, and then discuss lattice discretizations of fermions. We then turn to a description of the quenched approximation and why it is disappearing as a vehicle for QCD phenomenology. I describe recent claims for progress in simulations which include dynamical fermions and the interesting theoretical problems they raise. I conclude with brief descriptions of the calculations of matrix elements in heavy flavor systems and for kaons.Comment: Review for Int J Mod Phys A. 58 pages, latex, WSPC macros,, 22 postscript figure

Extended morphometric analysis of neuronal cells with Minkowski valuations

Minkowski valuations provide a systematic framework for quantifying different aspects of morphology. In this paper we apply vector- and tensor-valued Minkowski valuations to neuronal cells from the cat's retina in order to describe their morphological structure in a comprehensive way. We introduce the framework of Minkowski valuations, discuss their implementation for neuronal cells and show how they can discriminate between cells of different types.Comment: 14 pages, 18 postscript figure

Shedding Light on the "Dark Side" of Bd0B^0_d--Bˉd0\bar B^0_d Mixing through Bd→π+π−B_d\to\pi^+\pi^-, K→πννˉK\to\pi\nu\bar\nu and Bd,s→μ+μ−B_{d,s}\to\mu^+\mu^-

In a wide class of NP models, which can be motivated through generic arguments and within SUSY, we obtain large contributions to $B^0_d$--$\bar B^0_d$ mixing, but not to $\Delta B=1$ processes. If we assume such a scenario, the solutions $\phi_d\sim 47^\circ\lor 133^\circ$ for the $B^0_d$--$\bar B^0_d$ mixing phase implied by $A_{CP}^{mix}(B_d\to J/\psi K_S)$ cannot be converted directly into a constraint in the $\rho$--$\eta$ plane. However, we may complement $\phi_d$ with $|V_{ub}/V_{cb}|$ and the recently measured CP asymmetries in $B_d\to\pi^+ \pi^-$ to determine the unitarity triangle, with its angles $\alpha$, $\beta$ and $\gamma$. To this end, we have also to control penguin effects, which we do by means of the $B_d\to\pi^\mp K^\pm$ branching ratio. Interestingly, the present data show a perfectly consistent picture not only for the ``standard'' solution of $\phi_d\sim 47^\circ$, but also for $\phi_d\sim 133^\circ$. In the latter case, the preferred region for the apex of the unitarity triangle is in the second quadrant, allowing us to accommodate conveniently $\gamma>90^\circ$, which is also favoured by other non-leptonic B decays such as $B\to\pi K$. Moreover, also the prediction for BR(K^+\to\pi^+\nu\bar\nu}) can be brought to better agreement with experiment. Further strategies to explore this scenario with the help of $B_{d,s}\to\mu^+\mu^-$ decays are discussed as well.Comment: 26 pages, 3 figures, minor modifications, to appear in JHE

Research Report 2010

Introduction From the Chairperson Astronomy Atomic and Molecular Physics Condensed Matter Physics Physics Education Research and Public Lectures at WMU Personnel January 1-December 31, 201