699 research outputs found

    Geodesic motions in extraordinary string geometry

    Full text link
    The geodesic properties of the extraordinary vacuum string solution in (4+1) dimensions are analyzed by using Hamilton-Jacobi method. The geodesic motions show distinct properties from those of the static one. Especially, any freely falling particle can not arrive at the horizon or singularity. There exist stable null circular orbits and bouncing timelike and null geodesics. To get into the horizon {or singularity}, a particle need to follow a non-geodesic trajectory. We also analyze the orbit precession to show that the precession angle has distinct features for each geometry such as naked singularity, black string, and wormhole.Comment: 15 pages, 11 figure

    Production and optical properties of liquid scintillator for the JSNS2^{2} experiment

    Full text link
    The JSNS2^{2} (J-PARC Sterile Neutrino Search at J-PARC Spallation Neutron Source) experiment will search for neutrino oscillations over a 24 m short baseline at J-PARC. The JSNS2^{2} inner detector will be filled with 17 tons of gadolinium-loaded liquid scintillator (LS) with an additional 31 tons of unloaded LS in the intermediate Ī³\gamma-catcher and outer veto volumes. JSNS2^{2} has chosen Linear Alkyl Benzene (LAB) as an organic solvent because of its chemical properties. The unloaded LS was produced at a refurbished facility, originally used for scintillator production by the RENO experiment. JSNS2^{2} plans to use ISO tanks for the storage and transportation of the LS. In this paper, we describe the LS production, and present measurements of its optical properties and long term stability. Our measurements show that storing the LS in ISO tanks does not result in degradation of its optical properties.Comment: 7 pages, 4 figures

    Moduli Dynamics of AdS_3 Strings

    Full text link
    We construct a general class of solutions for a classical string in AdS_3 spacetime. The construction is based on a Pohlmeyer type reduction, with the sinh-Gordon model providing the general N-soliton solutions. The corresponding exact spiky string configurations are then reconstructed through the inverse scattering method. It is shown that the string moduli are determined entirely by those of the solitons.Comment: 22 pages, no figures; references adde

    A STUDY ON MULTI-MODELING FOR ARTIFACT RESTORATION

    Get PDF
    Restoration is carried out in order to restore damaged antiquities to their original form. Recently, research has been active in obtaining the target three-dimensional (3D) model by optical scanning and X-ray computed tomography (CT), as well as restoring artifacts via modeling. Because the cultural artifacts are restored in a virtual environment without direct contact with the cultural artifacts, secondary damage can be preserved. Furthermore, the restoration results can be used for the physical restoration of cultural artifacts via 3D printing. In this study, multi-digital modeling technology was used to restoration horse-shaped earthenware artifact that still had its missing part. After 3D printing, the restoration part was applied to the artifact. In order to record the shape of the artifact in detail, a high-precision 3D scanner was used to construct the shape of the artifact into a 3D model. Two models were then built as a reference for restoration: The legs of the excavated horse-shaped earthenware are believed to have been bent during burning, but they were reproduced in their entirety for restoration by conducting rigging and keyframe animation. For the restoration of the missing horse body, horse and rider-shaped vessels excavated from the same site were used as references. However, since the decorations on the reference surfaces obscured the horse body, a 3D model of the horse shape was obtained through X-ray CT segmentation modeling. Using the obtained model, the missing 3D horse body was restored. For the hind legs, the leg geometry reconstructed by the rigging was used as a reference. The hollow space inside the artifact and the structures that could be restored were further modeled. The finished model was completed by outputting a mock-up using a material extrusion system 3D printer, conducting a bonding test with actual artifacts, and finally creating the restoration model. Afterward, a photopolymerization system 3D printer is used to output the restoration part, and then it is applied to the artifacts through post-processing. A study for restoration artifacts based on multi-modeling techniques was proposed in this work. In particular, rigging and x-ray CT segmentation modeling were used to restoration the artifacts based on their original form and historical research. As such, multi-modeling techniques are an effective way to not only restore artifacts, but also to build a reference for restoration

    Particle Probe of Horava-Lifshitz Gravity

    Full text link
    Kehagias-Sfetsos black hole in Ho\v{r}ava-Lifshitz gravity is probed through particle geodesics. Gravitational force of KS black hole becomes weaker than that of Schwarzschild around horizon and interior space. Particles can be always scattered or trapped in new closed orbits, unlike those falling forever in Schwarzschild black. The properties of null and timelike geodesics are classified with values of coupling constants. The precession rates of the orbits are evaluated. The time trajectories are also classified under different values of coupling constants for both null and timelike geodesics. Physical phenomena that may be observable are discussed.Comment: 10 pages, 8 figure

    Semiclassical strings in AdS(3) X S^2

    Full text link
    In this paper, we investigate the semiclassical strings in AdS(3)XS^2, in which the string configuration of AdS(3) is classified to three cases depending on the parameters. Each of these has a different anomalous dimension proportional to logS, S^(1/3) and S, where S is a angular momentum on AdS(3). Further we generalize the dispersion relations for various string configuration on AdS(3)XS^2.Comment: 15 pages, added reference
    • ā€¦
    corecore