The Cosmic Web from Perturbation Theory

Context: Analyzing the large-scale structure (LSS) with galaxy surveys demands accurate structure formation models. Such models should ideally be fast and have a clear theoretical framework to rapidly scan a variety of cosmological parameter spaces without requiring large training data sets. Aims: This study aims to extend Lagrangian perturbation theory (LPT), including viscosity and vorticity, to reproduce the cosmic evolution from dark matter N-body calculations at the field level. Methods: We extend LPT to an Eulerian framework, dubbed eALPT. An ultraviolet regularisation through the spherical collapse model provided by Augmented LPT, turns out to be crucial at low redshifts. This enables modelling the stress tensor, with this introducing vorticity. The model has two free parameters apart from the choice of cosmology, redshift snapshots, cosmic volume, and the number of particles-cells. Results: We find that the cross-correlation of the dark matter distribution as compared to N-body solvers increases at $k = 1\,h$ Mpc$^{-1}$ and $z = 0$ from $\sim$55\% with the Zel'dovich approximation ($\sim$70\% with ALPT), to $\sim$95\% with three timesteps eALPT, and power spectra within percentage accuracy up to $k \simeq 0.3\,h$ Mpc$^{-1}$.Comment: 6 pages, 3 figure

All-sky angular power spectra from cleaned WISE×\timesSuperCOSMOS galaxy number counts

Aiming to extract cosmological information from linear scales of the WISE$\times$SuperCOSMOS photometric redshift catalog, we perform a characterization of the systematic effects associated with stellar content, evidencing the presence of contamination and obscuration. We create an integrated model for these effects (which together we call `usurper contamination'), devise a method to remove both of them simultaneously and show its functionality by applying it to a set of mock catalogs. When administered to WISE$\times$SuperCOSMOS data, our method shows to improve the measurements of angular power spectra on scales $\ell\lesssim15$ and the extraction of cosmological parameters therefrom, even though a significant excess of power remains at these scales. When ignoring scales $\ell<15$, we still find strong indications of systematics, albeit these can be localized in the southern equatorial hemisphere. An independent analysis of the northern hemisphere at $\ell\geq 15$ agrees with a $\Lambda$CDM model with parameters from the Planck satellite and gives $\Omega_{\mathrm{c}}=0.254\pm0.020$ and $\Omega_{\mathrm{b}}<0.065$ at 95% confidence limit when combined with priors on $H_0$, $A_s$ and $n_s$.Comment: 33 pages, 20 figures, 5 tables. Accepted for publication in JCA

Sistema multiobjetivo de soporte a decisiones para planificación de programación de operaciones

This research shows the design and construction of a multi objective optimization support system for decision making, DSS-SCHEDULER, in order to effectively perform naval shipbuilding operations, by managing to have a rational usage, under a limited capacity, of the installed capacity. The system creates the operational plan for the scheduling of operations as well as the allocation of all the resources related to the processes carried out at the plant, and, taking into account all the restrictions this type of service entails, generate a set of optimal solutions in order to comply with the objective functions as planned, such as costs and the promise for delivery dates to support the decision making process in scheduling Cotecmar’s industrial operations.La presente investigación muestra el diseño y construcción de un sistema de optimización Multiobjetivo de soporte a toma de decisiones, DSS-SCHEDULER, para realizar de manera efectiva la actividad de programación de operaciones en planta de astilleros navales, logrando una utilización racional, bajo capacidad finita, de la capacidad instalada, el cual realiza la creación de la planificación operativa de programación de operaciones y la asignación de todos los recursos asociados a los procesos que se realizan en la planta, y teniendo en cuenta todas las restricciones que conlleva estos servicios, generar un conjunto de soluciones óptimas cumpliendo con las funciones objetivo propuestas, como costos y promesa de fechas de entrega para apoyar la toma de decisiones de la programación de las operaciones industriales de Cotecmar

Report of the Age Calibration Exercise Analysis for Anchovy in Division 9a (IBERAS survey 2018)

In November 2018, a new acoustic survey (IBERAS) coordinated by IEO and IPMA was carried out in order to estimate the strength of sardine and anchovy recruitment in the Atlantic waters of the Iberian Peninsula (ICES Division 9a) and to map its distribution area. As well as determine the main biological characteristics of these species in the area. In January-February 2019, an otolith reading exercise was carried out on the anchovy from the survey to determine its age, with the objective of calibrating the age readings among the anchovy readers of the IEO and the IPMA, and estimating the accuracy and discrepancies in the determination of anchovy age among these readers. As well as, to obtain the age length keys of the surve

Minimum mass-radius ratio for charged gravitational objects

We rigorously prove that for compact charged general relativistic objects there is a lower bound for the mass-radius ratio. This result follows from the same Buchdahl type inequality for charged objects, which has been extensively used for the proof of the existence of an upper bound for the mass-radius ratio. The effect of the vacuum energy (a cosmological constant) on the minimum mass is also taken into account. Several bounds on the total charge, mass and the vacuum energy for compact charged objects are obtained from the study of the Ricci scalar invariants. The total energy (including the gravitational one) and the stability of the objects with minimum mass-radius ratio is also considered, leading to a representation of the mass and radius of the charged objects with minimum mass-radius ratio in terms of the charge and vacuum energy only.Comment: 19 pages, accepted by GRG, references corrected and adde

Ellipsoidal configurations in the de Sitter spacetime

The cosmological constant $\Lambda$ modifies certain properties of large astrophysical rotating configurations with ellipsoidal geometries, provided the objects are not too compact. Assuming an equilibrium configuration and so using the tensor virial equation with $\Lambda$ we explore several equilibrium properties of homogeneous rotating ellipsoids. One shows that the bifurcation point, which in the oblate case distinguishes the Maclaurin ellipsoid from the Jacobi ellipsoid, is sensitive to the cosmological constant. Adding to that, the cosmological constant allows triaxial configurations of equilibrium rotating the minor axis as solutions of the virial equations. The significance of the result lies in the fact that minor axis rotation is indeed found in nature. Being impossible for the oblate case, it is permissible for prolate geometries, with $\Lambda$ zero and positive. For the triaxial case, however, an equilibrium solution is found only for non-zero positive $\Lambda$. Finally, we solve the tensor virial equation for the angular velocity and display special effects of the cosmological constant there.Comment: 15 pages, 11 figures, published in Class. Quant. Grav. References adde

Probing dark energy with the next generation X-ray surveys of galaxy clusters

We present forecasts on the capability of future wide-area high-sensitivity X-ray surveys of galaxy clusters to yield constraints on the parameters defining the Dark Energy (DE) equation of state (EoS). Our analysis is carried out for future X-ray surveys which have enough sensitivity to provide accurate measurements of X-ray mass proxies and Fe-line based redshifts for about 2x10^4 clusters. We base our analysis on the Fisher Matrix formalism, by combining information on the cluster number counts and power spectrum, also including, for the first time in the analysis of the large scale cluster distribution, the effect of linear redshift-space distortions (RSDs). This study is performed with the main purpose of dissecting the cosmological information provided by geometrical and growth tests, which are both included in the analysis of number counts and clustering of galaxy clusters. We compare cosmological constraints obtained by assuming different levels of prior knowledge of the parameters which define the observable-mass X-ray relation. This comparison further demonstrates the fundamental importance of having a well calibrated observable-mass relation and, most importantly, its redshift evolution. Such a calibration can be achieved only by having at least $\sim 10^3$ net photon counts for each cluster included in the survey. We show that RSDs in the power spectrum analysis carry important cosmological information also when traced with galaxy clusters and the DE FoM increases by a factor of 8. Besides confirming the potential that large cluster surveys have in constraining the nature of DE, our analysis emphasizes that a full exploitation of the cosmological information carried by such surveys requires not only a large statistic but also a robust measurement of the mass proxies and redshifts for a significant fraction of the cluster sample, derived from the same X-ray survey data.Comment: 16 pages, 14 figures,published on MNRA

Euclid preparation: VII. Forecast validation for Euclid cosmological probes

Aims: The Euclid space telescope will measure the shapes and redshifts of galaxies to reconstruct the expansion history of the Universe and the growth of cosmic structures. The estimation of the expected performance of the experiment, in terms of predicted constraints on cosmological parameters, has so far relied on various individual methodologies and numerical implementations, which were developed for different observational probes and for the combination thereof. In this paper we present validated forecasts, which combine both theoretical and observational ingredients for different cosmological probes. This work is presented to provide the community with reliable numerical codes and methods for Euclid cosmological forecasts. / Methods: We describe in detail the methods adopted for Fisher matrix forecasts, which were applied to galaxy clustering, weak lensing, and the combination thereof. We estimated the required accuracy for Euclid forecasts and outline a methodology for their development. We then compare and improve different numerical implementations, reaching uncertainties on the errors of cosmological parameters that are less than the required precision in all cases. Furthermore, we provide details on the validated implementations, some of which are made publicly available, in different programming languages, together with a reference training-set of input and output matrices for a set of specific models. These can be used by the reader to validate their own implementations if required. / Results: We present new cosmological forecasts for Euclid. We find that results depend on the specific cosmological model and remaining freedom in each setting, for example flat or non-flat spatial cosmologies, or different cuts at non-linear scales. The numerical implementations are now reliable for these settings. We present the results for an optimistic and a pessimistic choice for these types of settings. We demonstrate that the impact of cross-correlations is particularly relevant for models beyond a cosmological constant and may allow us to increase the dark energy figure of merit by at least a factor of three