D Mesons in Nuclear Matter: A DN Coupled-Channel Equations Approach

A set of coupled two-body scattering equations is solved for the DN system embedded in an iso-symmetric nuclear matter. The in-medium behavior of charmed D mesons: (D^+,D^0), is investigated from the self-consistent solution within this scheme. The effective meson-baryon Lagrangian in charm quantum number one sector, the key ingredient in the present study, is adopted from a recent model by Hofmann and Lutz which has aimed at combining the charmed meson degree of freedom in a consistent manner with chiral unitary models. After a critical examination, the original model is modified in several important aspects, such as the method of regularization, in order to be more consistent and practical for our objective. The resultant interaction is used to reproduce the position and width of the s-wave \Lambda_c(2593) resonance in the isospin zero DN channel. In the isospin one channel, it generates a rather wide resonance at \~2770 MeV. The corresponding in-medium solution is then sought by incorporating Pauli blocking and the D- and \pi-meson dressing self-consistently. At normal nuclear matter density, the resultant \Lambda_c (2593) is found to stay narrow and shifted at a lower energy, while the I=1 resonance is lowered in position as well and broadened considerably. The possible implication of our findings on the J/\Psi suppression, etc. in relativistic heavy ion collisions is briefly discussed.Comment: 30 pages, 8 eps figures, some typos and coefficients corrected, published in Phys. Rev.

Convex Independence in Permutation Graphs

A set C of vertices of a graph is P_3-convex if every vertex outside C has at most one neighbor in C. The convex hull \sigma(A) of a set A is the smallest P_3-convex set that contains A. A set M is convexly independent if for every vertex x \in M, x \notin \sigma(M-x). We show that the maximal number of vertices that a convexly independent set in a permutation graph can have, can be computed in polynomial time

The structure of algebraic covariant derivative curvature tensors

We use the Nash embedding theorem to construct generators for the space of algebraic covariant derivative curvature tensors

Spectral microscopic mechanisms and quantum phase transitions in a 1D correlated problem

In this paper we study the dominant microscopic processes that generate nearly the whole one-electron removal and addition spectral weight of the one-dimensional Hubbard model for all values of the on-site repulsion $U$. We find that for the doped Mott-Hubbard insulator there is a competition between the microscopic processes that generate the one-electron upper-Hubbard band spectral-weight distributions of the Mott-Hubbard insulating phase and finite-doping-concentration metallic phase, respectively. The spectral-weight distributions generated by the non-perturbative processes studied here are shown elsewhere to agree quantitatively for the whole momentum and energy bandwidth with the peak dispersions observed by angle-resolved photoelectron spectroscopy in quasi-one-dimensional compounds.Comment: 18 pages, 2 figure

Analytic Bethe Ansatz for 1-D Hubbard model and twisted coupled XY model

We found the eigenvalues of the transfer matrices for the 1-D Hubbard model and for the coupled XY model with twisted boundary condition by using the analytic Bethe Ansatz method. Under a particular condition the two models have the same Bethe Ansatz equations. We have also proved that the periodic 1-D Hubbard model is exactly equal to the coupled XY model with nontrivial twisted boundary condition at the level of hamiltonians and transfer matrices.Comment: 22 pages, latex, no figure

Identidad y tipografía

Las sociedades de cada país poseen folklore que pone de manifiesto la idiosincrasia del pueblo y por consiguiente su historia. En ese sentido la creación de fuentes tipográficas orientadas a la identidad cultural en este caso con la región norte de nuestro país, supone, desde el punto de vista de diseño, nuevas oportunidades en el mercado de tipografía latinoamericana y, a su vez significa un aporte histórico-cultural importante y un compromiso para con la región y el país. Para entender lo que significa nación o país, es necesario conocer lo más cercano que tenemos; eso implica hablar de la región norte de Perú. En esta región nos vemos rodeados de un pasado cultural del cual solo conocemos por historia. No solo un escudo y un himno son los símbolos de identidad creados para representar una nación, dejando de lado lo que significaron siglos de evolución cultural que las sociedades de ese entonces nos transmitieron sabiamente, y que es todo lo que en la actualidad conocemos como patrimonio dentro de un museo. La región norte, donde se concentraron culturas que dieron increíbles aportes a nuestro país debería poseer no solo una bandera, un escudo y un himno;por el contrario debería poseer una fuente tipográfica que exprese y le de valor a tantos años de desarrollo cultural vividos por nuestros antepasados, y que por ahora,si hablamos netamente de diseño tipográfico nos lo expresa la marca Perú