A5087410877- Galaxies: Formation, Evolution, Phenomena
- Cosmology and Gravitation Theories
- Advanced X-ray Imaging Techniques
- Astronomy and Astrophysical Research
- Advanced X-ray and CT Imaging
- Black Holes and Theoretical Physics
- Stellar, planetary, and galactic studies
- X-ray Spectroscopy and Fluorescence Analysis
- Medical Imaging Techniques and Applications
- Radio Astronomy Observations and Technology
- Solar and Space Plasma Dynamics
- Astrophysics and Cosmic Phenomena
- Electrocatalysts for Energy Conversion
- Gamma-ray bursts and supernovae
- Particle physics theoretical and experimental studies
- Crystallography and Radiation Phenomena
- Building materials and conservation
- Astrophysical Phenomena and Observations
- Air Quality Monitoring and Forecasting
- Fuel Cells and Related Materials
- Shape Memory Alloy Transformations
- Optical and Acousto-Optic Technologies
- Statistical and numerical algorithms
- Cellular and Composite Structures
- Relativity and Gravitational Theory
Universidad Autónoma de Madrid
2019-2022
University of Florence
2022
University of Helsinki
2016-2019
University of Portsmouth
2019
Helsinki Institute of Physics
2016-2019
University of Geneva
2011-2016
University of Modena and Reggio Emilia
2013
Ferrari (Italy)
2013
University of Foggia
2006
Elettra-Sincrotrone Trieste S.C.p.A.
2002-2005
Cosmological models with Galileon gravity are an alternative to the standard ΛCDM paradigm testable predictions at level of its self-accelerating solutions for expansion history, as well large-scale structure formation. Here, we place constraints on full parameter space these using data from cosmic microwave background (CMB) (including lensing), baryonic acoustic oscillations (BAO) and Integrated Sachs-Wolfe (ISW) effect. We pay special attention ISW effect which use cross-spectra, CℓTg, CMB...
We present some accurate and efficient computations of large scale structure observables, obtained with a modified version the CLASS code which is made publicly available. This includes all relativistic corrections computes both power spectrum Cl(z1,z2) corresponding correlation function xi(theta,z1,z2) in linear perturbation theory. For Gaussian initial perturbations, these quantities contain full information encoded matter distribution at level illustrate usefulness our for cosmological...
We determine the number counts to second order in cosmological perturbation theory Poisson gauge and allowing for anisotropic stress. The calculation is performed using an innovative approach based on recently proposed "geodesic light-cone" gauge. This allows us a purely geometric way, without Einstein's equation. result valid general dark energy models (most) modified gravity models. then evaluate numerically relevant contributions bispectrum. In particular we consider terms involving...
We investigate how the lensing potential can be measured tomographically with future galaxy surveys using their number counts. Such a measurement is an independent test of standard ΛCDM framework and used to discern modified theories gravity. perform Fisher matrix forecast based on angular-redshift power spectra, assuming specifications consistent photometric Euclid-like spectroscopic SKA-like surveys. For survey we derive fitting formula for magnification bias. Our analysis suggests that...
We present the first determination of Hubble constant H_{0} from strong lensing time delay data and type Ia supernova luminosity distances that is independent cosmological model. also determine spatial curvature model independently. assume light propagation over long described by Friedmann-Lemaître-Robertson-Walker (FLRW) metric geometrical optics holds, but make no assumption about contents Universe or theory gravity on scales. find H_{0}=75.7_{-4.4}^{+4.5} km/s/Mpc...
We estimate the sensitivity of future galaxy surveys to cosmological parameters, using redshift dependent angular power spectra number counts, $C_\ell(z_1,z_2)$, calculated with all relativistic corrections at first order in perturbation theory. pay special attention dependence non-linearity scale and present Fisher matrix forecasts for Euclid-like DES-like surveys. compare standard $P(k)$ analysis new $C_\ell(z_1,z_2)$ method. show that photometric redshifts performs significantly better...
We present the results of a search for galaxy clusters and groups in $\sim2$ square degree COSMOS field using all available X-ray observations from XMM-Newton Chandra observatories. reach an flux limit $3\times10^{-16}\;ergs\;cm^{-2}\;s^{-1}$ 0.5--2 keV range, identify 247 with $M_{200c}=8\times10^{12}-3\times10^{14}\;M_{\odot}$ at redshift range $0.08\leq z<1.53$, multiband photometric master spectroscopic catalogues COSMOS. The centres are determined high-resolution imaging. investigate...
We investigate the cosmological dependence and constraining power of large-scale galaxy correlations, including all redshift-distortions, wide-angle, lensing gravitational potential effects on linear scales. analyze information present in convergence terms describing so-called "relativistic effects," we find that, while smaller than contained intrinsic clustering, it is not negligible. how neglecting them does bias measurements performed by future spectroscopic photometric surveys such as...
We discuss the dominant terms of relativistic galaxy number counts to second order in cosmological perturbation theory on sub-Hubble scales and intermediate large redshifts. In particular, we determine their contribution bispectrum. addition already known from Newtonian theory, find that there are a series additional `lensing-like' which contribute derive analytical expressions for full leading bispectrum evaluate it numerically different configurations, indicating how they can be measured...
We demonstrate the importance of including lensing contribution in galaxy clustering analyses with large redshift surveys. It is well known that radial cross-correlations between different bins surveys are dominated by lensing. But we show here also neglecting autocorrelations within one bin severely biases cosmological parameter estimation leads to significant shifts for several parameters, most notably scalar spectral index and neutrino mass scale. Especially latter main targets future
We address the impact of consistent modifications gravity on largest observable scales, focusing relativistic effects in galaxy number counts and cross-correlation between matter large scale structure (LSS) distribution cosmic microwave background (CMB). Our analysis applies to a very broad class general scalar-tensor theories encoded Horndeski Lagrangian is fully linear retaining full dynamics scalar field not assuming quasi-static evolution. As particular examples we consider...
We compute the redshift-dependent angular bispectrum of galaxy number counts at tree-level, including nonlinear clustering bias and estimating numerically for first time effect redshift space distortions (RSD). show that narrow bins amplitude RSD is comparable with matter density perturbations. While our numerical results only include terms relevant on sub-horizon scales, formalism can readily be extended to full tree-level bispectrum. Our approach does not rely flat-sky approximation it...
ABSTRACT: Phase-sensitive X-ray microtomography was used as a nondestructive imaging technique for the computerized reconstruction of three-dimensional (3D) images bread crumb microstructure. After image acquisition, numerical algorithms were slice reconstruction. Successively, 3D rendered and quantitatively analyzed. Stereological analyses performed to determine void volume fraction some directionally dependent parameters, such cell wall number, thickness, spacing, specific surface....
ABSTRACT: The evaluation of bread quality can be carried out by performing a nondestructive investigation its microstructure, which in turn performed adapting image analysis techniques that enables one to obtain rapid, objective, and quantitative information. A suitable reliable experimental methodology investigate the porous structure means numerical processing, without any sample preparation, has been presented this work. Different types breads having varying degrees porosity were studied...
We argue that from observations alone, only the transverse power spectrum $C_\ell(z_1,z_2)$ and corresponding correlation function $\xi(\theta,z_1,z_2)$ can be measured these contain full three dimensional information. determine two point galaxy at linear order in perturbation theory. Redshift space distortions are taken into account for arbitrary angular redshift separations. discuss shape of longitudinal transversal functions which very different each other their real counterpart. then go...
We modified the CLASS code in order to include relativistic galaxy number counts spatially curved geometries; we present formalism and study effect of corrections on spatial curvature. The new version is now publicly available. Using a Fisher matrix analysis, investigate how measurements curvature parameter ΩK with future surveys are affected by effects, which influence observations large scale distribution. These effects contributions from cosmic magnification, Doppler terms involving...
A system for in vivo breast imaging with monochromatic x-rays has been designed and built at the synchrotron radiation facility Elettra Trieste (Italy) will be operational 2004. The design involves possibility of performing both planar mammography tomography. In present work, first results obtained a test set-up tomography are shown discussed. Tomographic images vitro breasts were acquired using x-ray beams energy range 20-28 keV linear array silicon pixel detector. Tomograms reconstructed...
If the FRW metric is a good approximation on large scales, then distance and expansion rate, as well different notions of distance, satisfy certain consistency conditions. We fit JLA SNIa data to determine expected amplitude violation these conditions if accelerated due backreaction. Adding cosmic clock BAO rate data, we also model-independently current observational limits such violation. find that predicted maximum backreaction |kH| ≲ 1 (95% C.I.) same order constraints 1, precise numbers...
This report discusses the optimization strategy, theoretical background and first experimental data of a new refractive lens for focusing X-rays. In order to reduce absorption X-rays in this transmission lens, optically passive material was removed from necessarily concave shape highly regular pattern. The feature dimensions require production replication by deep X-ray lithography, which allows shaping only one dimension. Consequently such can focus direction only, so crossed pair is needed...
The heating microscope is a widely used instrument in many industrial applications, especially the ceramic field, to obtain information on sintering behavior and, indirectly, viscosity curve of glass. It therefore important for study glass technology. Usually, microscopes work by taking images sample outline, during preset thermal cycle, which define five characteristic temperatures corresponding particular shapes specimen. first two can also be extracted from curves provided instrument. In...
We performed a detailed study of the evolution star formation rate (SFR) and stellar mass brightest group galaxies (BGGs) their relative contribution to total baryon budget within R200 (|$f^{{\rm BGG}}_{{\rm b},200}$|). The sample comprises 407 BGGs selected from X-ray groups (M200 = 1012.8–1014 M⊙) out z ∼ 1.3 identified in Cosmic Evolution Survey (COSMOS), XMM Large-Scale Structure survey (XMM-LSS), All-Wavelength Extended Groth strip International (AEGIS) fields. find that constitute...