Pion Interferometry From A Relativistic Fluid With A First Order Phase Transition In CERN-SPS 158 GeV/A Pb+Pb Collisions

We investigate pion source sizes through the Yano-Koonin-Podgoretski\u{\i} (YKP) parametrization for the Hanbury-Brown Twiss (HBT) effect in the CERN-SPS 158 GeV/A central collisions. We calculate two-particle correlation functions numerically based on a (3+1)-dimensional relativistic hydrodynamics with a first order phase transition and analyze the pair momentum dependence of the HBT radii extracted from the YKP parametrization in detail. We find that even in the case of a first order phase transition, expansion and the surface dominant freeze-out make the source in the hydrodynamical model opaque significantly. Consequently, the interpretation of the temporal radius parameter as the time duration becomes unavailable for the hydrodynamical model.Comment: 5 pages, LaTeX with six eps figures, Contribution to 'International Workshop XXVIII on Gross Properties of Nuclei And Nuclear Excitations'. Hirchegg, Austria, Jan 16-22, 200

Analysis of one- and two-particle spectra at RHIC based on a hydrodynamical model

We calculate the one-particle hadronic spectra and correlation functions of pions based on a hydrodynamical model. Parameters in the model are so chosen that the one-particle spectra reproduce experimental results of $\sqrt{s}=130A$GeV Au+Au collisions at RHIC. Based on the numerical solution, we discuss the space-time evolution of the fluid. Two-pion correlation functions are also discussed. Our numerical solution suggests the formation of the quark-gluon plasma with large volume and low net baryon density.Comment: LaTeX, 4pages, 4 figures. To appear in the proceedings of Fourth International Conference on Physics and Astrophysics of Quark-Gluon Plasma (ICPAQGP-2001), Nov 26-30, 2001, Jaipur, Indi

Helical mode conversion using conical reflector

In a recent paper, Mansuripur et al. [Phys. Rev. A 84, 033813 (2011)] indicated and numerically verified the generation of the helical wavefront of optical beams using a conical-shape reflector. Because the optical reflection is largely free from chromatic aberrations, the conical reflector has an advantage of being able to manipulate the helical wavefront with broadband light such as white light or short light pulses. In this study, we introduce geometrical understanding of the function of the conical reflector using the spatially-dependent geometric phase, or more specifically, the spin redirection phase. We also present a theoretical analysis based on three-dimensional matrix calculus and elucidate relationships of the spin, orbital, and total angular momenta between input and output beams. These analyses are very useful when designing other optical devices that utilize spatially-dependent spin redirection phases. Moreover, we experimentally demonstrate the generation of helical beams from an ordinary Gaussian beam using a metallic conical-shape reflector.Comment: 7 pages, 7 figure

Knowledge management and human trafficking: using conceptual knowledge representation, text analytics and open-source data to combat organized crime

Globalization, the ubiquity of mobile communications and the rise of the web have all expanded the environment in which organized criminal entities are conducting their illicit activities, and as a result the environment that law enforcement agencies have to police. This paper triangulates the capability of open-source data analytics, ontological knowledge representation and the wider notion of knowledge management (KM) in order to provide an effective, interdisciplinary means to combat such threats, thus providing law enforcement agencies (LEA’s) with a foundation of competitive advantage over human trafficking and other organized crime

Live imaging of whole mouse embryos during gastrulation : migration analyses of epiblast and mesodermal cells

During gastrulation in the mouse embryo, dynamic cell movements including epiblast invagination and mesodermal layer expansion lead to the establishment of the three-layered body plan. The precise details of these movements, however, are sometimes elusive, because of the limitations in live imaging. To overcome this problem, we developed techniques to enable observation of living mouse embryos with digital scanned light sheet microscope (DSLM). The achieved deep and high time-resolution images of GFP-expressing nuclei and following 3D tracking analysis revealed the following findings: (i) Interkinetic nuclear migration (INM) occurs in the epiblast at embryonic day (E)6 and 6.5. (ii) INM-like migration occurs in the E5.5 embryo, when the epiblast is a monolayer and not yet pseudostratified. (iii) Primary driving force for INM at E6.5 is not pressure from neighboring nuclei. (iv) Mesodermal cells migrate not as a sheet but as individual cells without coordination

Charmonium properties in hot quenched lattice QCD

We study the properties of charmonium states at finite temperature in quenched QCD on large and fine isotropic lattices. We perform a detailed analysis of charmonium correlation and spectral functions both below and above $T_c$. Our analysis suggests that both S wave states ($J/\psi$ and $\eta_c$) and P wave states ($\chi_{c0}$ and $\chi_{c1}$) disappear already at about $1.5 T_c$. The charm diffusion coefficient is estimated through the Kubo formula and found to be compatible with zero below $T_c$ and approximately $1/\pi T$ at $1.5 T_c\lesssim T\lesssim 3 T_c$.Comment: 32 pages, 19 figures, typo corrected, discussions on isotropic vs anisotropic lattices expanded, published versio

The Influence of UVA and Visible Radiation on Acute Damage by Short-Wave UVR (λ < 320 nm)

The influence of UVA and visible radiation on the acute damage by short-wave ultraviolet radiation (UVR) (λ < 320 nm) was investigated in human volunteers, using delayed erythema and sunburn cell production as markers of injury. It was found that subsequent exposure to UVA + visible radiation produced a significant reduction of the threshold erythema dose by short-wave UVR, in a dose-dependent manner. Subsequent exposures to varying doses of UVA + visible radiation, as well as to visible light alone failed to influence sunburn cell production. It is concluded that there is a positive interaction between short-wave UVR and UVA in the induction of delayed erythema, but this may not apply to epidermal cell injury. Photorecovery was not observed

Hydrodynamical evolution near the QCD critical end point

Hydrodynamical calculations have been successful in describing global observables in ultrarelativistic heavy ion collisions, which aim to observe the production of the quark-gluon plasma. On the other hand, recently, a lot of evidence that there exists a critical end point (CEP) in the QCD phase diagram has been accumulating. Nevertheless, so far, no equation of state with the CEP has been employed in hydrodynamical calculations. In this paper, we construct the equation of state with the CEP on the basis of the universality hypothesis and show that the CEP acts as an attractor of isentropic trajectories. We also consider the time evolution in the case with the CEP and discuss how the CEP affects the final state observables, such as the correlation length, fluctuation, chemical freezeout, kinetic freezeout, and so on. Finally, we argue that the anomalously low kinetic freezeout temperature at the BNL Relativistic Heavy Ion Collider suggests the possibility of the existence of the CEP.Comment: 13 pages, 12 figures, accepted for publication in Physical Review

Cilia at the node of mouse embryos sense fluid flow for left-right determination via Pkd2

Unidirectional fluid flow plays an essential role in the breaking of left-right (L-R) symmetry in mouse embryos, but it has remained unclear how the flow is sensed by the embryo. We report that the Ca2+ channel Polycystin-2 (Pkd2) is required specifically in the perinodal crown cells for sensing the nodal flow. Examination of mutant forms of Pkd2 shows that the ciliary localization of Pkd2 is essential for correct L-R patterning. Whereas Kif3a mutant embryos, which lack all cilia, failed to respond to an artificial flow, restoration of primary cilia in crown cells rescued the response to the flow. Our results thus suggest that nodal flow is sensed in a manner dependent on Pkd2 by the cilia of crown cells located at the edge of the node.CREST of the Japan Science and Technology Corporation; NIH [P30 DK090744]; Human Frontier Science Program [ST00246/2003C]; Deutsche Forschungsgemeinschaft [PE 853/2]; Japan Society for the Promotion of Science; American Heart Association [R10682]info:eu-repo/semantics/publishedVersio