Cosmic web alignments with the shape, angular momentum and peculiar velocities of dark matter haloes

We study the alignment of dark matter haloes with the cosmic web characterized by the tidal and velocity shear fields. We focus on the alignment of their shape, angular momentum and peculiar velocities. We use a cosmological N-body simulation that allows to study dark matter halos spanning almost five orders of magnitude in mass ($10^{9}$-$10^{14}$) $h^{-1}$$M_{\odot}$ and spatial scales of $(0.5$-$1.0)$ $h^{-1}$ Mpc to define the cosmic web. We find that the halo shape presents the strongest alignment along the smallest tidal eigenvector, e.g. along filaments and walls, with a signal that gets stronger as the halo mass increases. In the case of the velocity shear field only massive halos $>10^{12}$ $h^{-1}$$M_{\odot}$ tend to have their shapes aligned along the largest tidal eigenvector; that is, perpendicular to filaments and walls. For the angular momentum we find alignment signals only for halos more massive than $10^{12}$ $h^{-1}$$M_{\odot}$ both in the tidal and velocity shear webs where the preferences are for it to be parallel to the middle eigenvector; perpendicular to filaments and parallel to walls. Finally, the peculiar velocities show a strong alignment along the smallest tidal eigenvector for all halo masses; halos move along filaments and walls. In the velocity shear the same alignment is present but weaker and only for haloes less massive than $10^{12}$ $h^{-1}$$M_{\odot}$. Our results clearly show that the two different algorithms we used to define the cosmic web describe different physical aspects of non-linear collapse and should be used in a complementary way to understand the effect of the cosmic web on galaxy evolution.Comment: 14 pages, 5 figures, MNRAS accepte

Desarrollo autosostenible de la implementación de la construcción de la Escuela Porvenir en la utilización de material reciclable

Trabajo de InvestigaciónEl proyecto se basa en el diseño para la construcción de una escuela usando materiales reciclables los cuales son de gran ayuda ya que es un sistema económico y puede ser implantado en la población de bajos recursos.PregradoIngeniero Civi

Gravitational radiation from precessing accretion disks in gamma-ray bursts

We study the precession of accretion disks in the context of gamma-ray burst inner engines. Our aim is to quantitatively estimate the characteristics of gravitational waves produced by the precession of the transient accretion disk in gamma-ray bursts. We evaluate the possible periods of disk precession caused by the Lense-Thirring effect using an accretion disk model that allows for neutrino cooling. Assuming jet ejection perpendicular to the disk plane and a typical intrinsic time-dependence for the burst, we find gamma-ray light curves that have a temporal microstructure similar to that observed in some reported events. The parameters obtained for the precession are then used to evaluate the production of gravitational waves. We find that the precession of accretion disks of outer radius smaller than $10^8$ cm and accretion rates above 1 solar mass per second could be detected by Advanced LIGO if they occur at distances of less than 100 Mpc. We conclude that the precession of a neutrino-cooled accretion disk in long gamma-ray bursts can be probed by gravitational wave astronomy. Precession of the disks in short gamma-ray events is undetectable with the current technology.Comment: 5 pages, 5 figures, accepted for publication in A&

Vaca pa’ la Vaca

Trabajo de síntesisEs una nueva alternativa de inversión en el sector Ganadero de Colombia, permite ser parte de una comunidad con excedentes de liquidez a partir de un monto mínimo de $150.000 pesos equivalente a una unidad, los cuales podrán ser negociados en nuestra plataforma.INTRODUCCIÓN E INFORMACIÓN GENERAL RESUMEN EJECUTIVO 1. DESCRIPCIÓN DEL PROYECTO DE INNOVACIÓN FINANCIERA CON BASE TECNOLÓGICA Y SOCIAL 2. OBJETIVOS DE VACA PA` LA VACA 3. INFORMACIÓN PRODUCTOS FINANCIEROS 4. ENCUESTA 5. ENTREVISTA 6. PLANEACIÓN ESTRATÉGICA 7. CONCEPTO DEL PRODUCTO, SERVICIO/MEJORA O FORTALECIMIENTO 8. LOGO VACA PA´ LA VACA 9. ESTUDIO DE MERCADO 10. FORMULACIÓN DEL MODELO DE NEGOCIO - PRODUCTO MÍNIMO VIABLE 11. ESTUDIO TÉCNICO 12. ESTUDIO ECONÓMICO Y FINANCIERO 13. ESTUDIO SOCIAL Y AMBIENTAL 14. NORMATIVIDAD 15. CONCLUSIONES 16. AGRADECIMIENTOS BIBLIOGRAFÍA ANEXOSEspecializaciónEspecialista en Formulación y Evaluación Social y Económica de Proyecto

Scaling of the elastic contribution to the surface free energy of a nematic on a sawtoothed substrate

We characterize the elastic contribution to the surface free energy of a nematic in presence of a sawtooth substrate. Our findings are based on numerical minimization of the Landau-de Gennes model and analytical calculations on the Frank-Oseen theory. The nucleation of disclination lines (characterized by non-half-integer winding numbers) in the wedges and apexes of the substrate induces a leading order proportional to qlnq to the elastic contribution to the surface free energy density, q being the wavenumber associated with the substrate periodicity.Comment: 7 pages, 6 figures, accepted for publication in Physical Review

Diseño y propuesta de un plan de mercadeo orientado a la comercialización de productos sellados de fluidos para la empresa técnicas de fluidos

Reseña de la empresa Técnica de Fluidos -- Historia y conceptos del sellado de fluidos -- Diagnóstico situacional

3D short-range wetting and nonlocality

Analysis of a microscopic Landau-Ginzburg-Wilson model of 3D short-ranged wetting shows that correlation functions are characterized by two length scales, not one, as previously thought. This has a simple diagrammatic explanation using a nonlocal interfacial Hamiltonian and yields a thermodynamically consistent theory of wetting in keeping with exact sum rules. For critical wetting the second length serves to lower the cutoff in the spectrum of interfacial fluctuations determining the repulsion from the wall. We show how this corrects previous renormalization group predictions for fluctuation effects, based on local interfacial Hamiltonians. In particular, lowering the cutoff leads to a substantial reduction in the effective value of the wetting parameter and prevents the transition being driven first order. Quantitative comparison with Ising model simulation studies due to Binder, Landau, and co-workers is also mad