Three-body hadron systems with strangeness

Recently, many efforts are being put in studying three-hadron systems made of mesons and baryons and interesting results are being found. In this talk, I summarize the main features of the formalism used to study such three hadron systems with strangeness $S=-1,0$ within a framework built on the basis of unitary chiral theories and solution of the Faddeev equations. In particular, I present the results obtained for the $\pi\bar{K}N$, $K\bar{K}N$ and $KK\bar{K}$ systems and their respective coupled channels. In the first case, we find four $\Sigma$'s and two $\Lambda$'s with spin-parity $J^P=1/2^+$, in the 1500-1800 MeV region, as two meson-one baryon s-wave resonances. In the second case, a $1/2^+$ $N^*$ around 1900 MeV is found. For the last one a kaon close to 1420 MeV is formed, which can be identified with K(1460).Comment: Proceeding written for the HYP2012 conferenc

Ultrafast laser welding of ceramics.

Welding of ceramics is a key missing component in modern manufacturing. Current methods cannot join ceramics in proximity to temperature-sensitive materials like polymers and electronic components. We introduce an ultrafast pulsed laser welding approach that relies on focusing light on interfaces to ensure an optical interaction volume in ceramics to stimulate nonlinear absorption processes, causing localized melting rather than ablation. The key is the interplay between linear and nonlinear optical properties and laser energy-material coupling. The welded ceramic assemblies hold high vacuum and have shear strengths comparable to metal-to-ceramic diffusion bonds. Laser welding can make ceramics integral components in devices for harsh environments as well as in optoelectronic and/or electronic packages needing visible-radio frequency transparency

Reentrant Metallic Behavior of Graphite in the Quantum Limit

Magnetotransport measurements performed on several well-characterized highly oriented pyrolitic graphite and single crystalline Kish graphite samples reveal a reentrant metallic behavior in the basal-plane resistance at high magnetic fields, when only the lowest Landau levels are occupied. The results suggest that the quantum Hall effect and Landau-level-quantization-induced superconducting correlations are relevant to understand the metallic-like state(s) in graphite in the quantum limit.Comment: 4 pages, 5 figure

Lie symmetries and solitons in nonlinear systems with spatially inhomogeneous nonlinearities

Using Lie group theory and canonical transformations we construct explicit solutions of nonlinear Schrodinger equations with spatially inhomogeneous nonlinearities. We present the general theory, use it to show that localized nonlinearities can support bound states with an arbitrary number solitons and discuss other applications of interest to the field of nonlinear matter waves

Inositol phosphate kinases in the eukaryote landscape

Inositol phosphate encompasses a large multifaceted family of signalling molecules that originate from the combinatorial attachment of phosphate groups to the inositol ring. To date, four distinct inositol kinases have been identified, namely, IPK, ITPK, IPPK (IP5-2K), and PPIP5K. Although, ITPKs have recently been identified in archaea, eukaryotes have taken advantage of these enzymes to create a sophisticated signalling network based on inositol phosphates. However, it remains largely elusive what fundamental biochemical principles control the signalling cascade. Here, we present an evolutionary approach to understand the development of the 'inositol phosphate code' in eukaryotes. Distribution analyses of these four inositol kinase groups throughout the eukaryotic landscape reveal the loss of either ITPK, or of PPIP5K proteins in several species. Surprisingly, the loss of IPPK, an enzyme thought to catalyse the rate limiting step of IP6 (phytic acid) synthesis, was also recorded. Furthermore, this study highlights a noteworthy difference between animal (metazoan) and plant (archaeplastida) lineages. While metazoan appears to have a substantial amplification of IPK enzymes, archaeplastida genomes show a considerable increase in ITPK members. Differential evolution of IPK and ITPK between plant and animal lineage is likely reflective of converging functional adaptation of these two types of inositol kinases. Since, the IPK family comprises three sub-types IPMK, IP6K, and IP3-3K each with dedicated enzymatic specificity in metazoan, we propose that the amplified ITPK group in plant could be classified in sub-types with distinct enzymology

Spatio-temporal vortex beams and angular momentum

We present a space-time generalization of the known spatial (monochromatic) wave vortex beams carrying intrinsic orbital angular momentum (OAM) along the propagation direction. Generic spatio-temporal vortex beams are polychromatic and can carry intrinsic OAM at an arbitrary angle to the mean momentum. Applying either (i) a transverse wave-vector shift or (ii) a Lorentz boost to a monochromatic Bessel beam, we construct a family of either (i) time-diffracting or (ii) non-diffracting spatio-temporal Bessel beams, which are exact solutions of the Klein-Gordon wave equations. The proposed spatio-temporal OAM states are able to describe either photon or electron vortex states (both relativistic and nonrelativistic), and can find applications in particle collisions, optics of moving media, quantum communications, and astrophysics.Comment: 9 pages, 6 figures, to appear in Phys. Rev.

Boson stars in massive dilatonic gravity

We study equilibrium configurations of boson stars in the framework of a class scalar-tensor theories of gravity with massive gravitational scalar (dilaton). In particular we investigate the influence of the mass of the dilaton on the boson star structure. We find that the masses of the boson stars in presence of dilaton are close to those in general relativity and they are sensitive to the ratio of the boson mass to the dilaton mass within a typical few percent. It turns out also that the boson star structure is mainly sensitive to the mass term of the dilaton potential rather to the exact form of the potential.Comment: 9 pages, latex, 9 figures, one figure dropped, new comments added, new references added, typos correcte

Can Strong Gravitational Lensing Constrain Dark Energy?

We discuss the ratio of the angular diameter distances from the source to the lens, $D_{ds}$, and to the observer at present, $D_{s}$, for various dark energy models. It is well known that the difference of $D_s$s between the models is apparent and this quantity is used for the analysis of Type Ia supernovae. However we investigate the difference between the ratio of the angular diameter distances for a cosmological constant, $(D_{ds}/D_{s})^{\Lambda}$ and that for other dark energy models, $(D_{ds}/D_{s})^{\rm{other}}$ in this paper. It has been known that there is lens model degeneracy in using strong gravitational lensing. Thus, we investigate the model independent observable quantity, Einstein radius ($\theta_E$), which is proportional to both $D_{ds}/D_s$ and velocity dispersion squared, $\sigma_v^2$. $D_{ds}/D_s$ values depend on the parameters of each dark energy model individually. However, $(D_{ds}/D_s)^{\Lambda} - (D_{ds}/D_{s})^{\rm{other}}$ for the various dark energy models, is well within the error of $\sigma_v$ for most of the parameter spaces of the dark energy models. Thus, a single strong gravitational lensing by use of the Einstein radius may not be a proper method to investigate the property of dark energy. However, better understanding to the mass profile of clusters in the future or other methods related to arc statistics rather than the distances may be used for constraints on dark energy.Comment: 15 pages, 13 figures, Accepted in PR