A5048966045- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Cosmology and Gravitation Theories
- Stellar, planetary, and galactic studies
- Radio Astronomy Observations and Technology
- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Geophysics and Gravity Measurements
- Astrophysics and Star Formation Studies
- Black Holes and Theoretical Physics
- CCD and CMOS Imaging Sensors
- Solar and Space Plasma Dynamics
- Astronomical Observations and Instrumentation
- Adaptive optics and wavefront sensing
- Astrophysical Phenomena and Observations
- Scientific Research and Discoveries
- Pulsars and Gravitational Waves Research
- Neutrino Physics Research
- Seismic Imaging and Inversion Techniques
- Photocathodes and Microchannel Plates
- Antenna Design and Optimization
- Reservoir Engineering and Simulation Methods
- Astro and Planetary Science
- Gaussian Processes and Bayesian Inference
- Calibration and Measurement Techniques
Laboratoire d’Astrophysique de Marseille
2011-2024
Centre National de la Recherche Scientifique
2013-2024
Aix-Marseille Université
2013-2024
Château Gombert
2016-2024
CEA Paris-Saclay
2006-2007
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2006-2007
Direction des énergies
2007
Institut d'Astrophysique de Paris
2004-2006
Institut National de Physique Nucléaire et de Physique des Particules
2006
DSM (Netherlands)
2006
We present the XXL Survey, largest XMM programme totaling some 6.9 Ms to date and involving an international consortium of roughly 100 members. The Survey covers two extragalactic areas 25 deg2 each at a point-source sensitivity ~ 5E-15 erg/sec/cm2 in [0.5-2] keV band (completeness limit). survey's main goals are provide constraints on dark energy equation state from space-time distribution clusters galaxies serve as pathfinder for future, wide-area X-ray missions. review science objectives,...
Current efforts in observational cosmology are focused on characterizing the mass-energy content of Universe. We present results from a geometric test based strong lensing galaxy clusters. Based Hubble Space Telescope images and extensive ground-based spectroscopic follow-up massive cluster Abell 1689, we used parametric model to simultaneously constrain mass distribution dark energy equation state. Combining our cosmological constraints with those X-ray clusters Wilkinson Microwave...
The role of the cosmic web in shaping galaxy properties is investigated GAMA spectroscopic survey redshift range $0.03 \leq z 0.25$. stellar mass, $u - r$ dust corrected colour and specific star formation rate (sSFR) galaxies are analysed as a function their distances to 3D features, such nodes, filaments walls, reconstructed by DisPerSE. Significant mass type/colour gradients found for whole population, with more massive and/or passive being located closer filament wall than less...
This article investigates the signatures of various models dark energy on weak gravitational lensing, including complementarity linear and nonlinear regimes. It quintessence their extension to scalar-tensor gravity. The effects induced by this simplest general relativity are discussed. is shown that, given constraints in Solar System, such as a quadratic nonminimal coupling do not leave any that can be detected while other models, runaway dilaton, which include attraction toward relativity,...
In the theory of structure formation, galaxies are biased tracers underlying matter density field. The statistical relation between galaxy and field is commonly referred to as bias. this paper, we test linear bias model with weak-lensing clustering measurements in 2 deg2 COSMOS We estimate redshifts z = 0.2 1 over correlation scales R h−1 Mpc 15 Mpc. focus on three samples, selected flux (simultaneous cuts I814W < 26.5 Ks 24) stellar mass (109 M* 1010 h−2 M☉ 1011 M☉). At > Mpc, our support a...
Aims.Dark energy can be investigated in two complementary ways, by considering either general parameterizations or physically well-defined models. Following the second route, we explore observational constraints on quintessence models where acceleration of our universe is driven a slow-rolling scalar field. Using weak lensing data to investigate high-energy motivated dark for first time, analysis focuses cosmic shear, examining how surveys constrain energy, discussing limitations due lack...
MSE is an 11.25m aperture observatory with a 1.5 square degree field of view that will be fully dedicated to multi-object spectroscopy. More than 3200 fibres feed spectrographs operating at low (R ~ 2000 - 3500) and moderate 6000) spectral resolution, approximately 1000 fibers high 40000) resolution. designed enable transformational science in areas as diverse tomographic mapping the interstellar intergalactic media; in-situ chemical tagging thick disk halo stars; connecting galaxies their...
In scalar-tensor theories of gravity, the equation state dark energy, $w$, can become smaller than $\ensuremath{-}1$ without violating any energy condition. The value $w$ today is tied to level deviations from general relativity which, in turn, constrained by solar system and pulsars timing experiments. conditions on these local constraints for be significantly less are established. It demonstrated that this requires us consider differ Jordan-Fierz-Brans-Dicke theory involve either a steep...
The baryon acoustic oscillation (BAO) feature in the power spectrum of galaxies provides a standard ruler to probe accelerated expansion Universe. current surveys covering comoving volume sufficient unveil BAO scale are limited redshift z ≲ 0.7. In this paper, we study several galaxy selection schemes aiming at building an emission-line (ELG) sample range 0.6 < 1.7 that would be suitable for future studies using Baryonic Oscillation Spectroscopic Survey (BOSS) spectrograph on Sloan Digital...
We use measurements of cosmic shear from CFHTLS, combined with WMAP-5 microwave background anisotropy data, baryonic acoustic oscillations SDSS and 2dFGRS supernovae data SNLS Gold-set, to constrain the neutrino mass. obtain a 95% confidence level upper limit 0.54 eV for sum masses, lower 0.03 eV. The preference massive neutrinos vanishes when shear-measurement systematics are included in analysis.
The baryon acoustic oscillation (BAO) feature in the two-point correlation function of galaxies supplies a standard ruler to probe expansion history Universe. We study here several galaxy selection schemes, aiming at building an emission-line (ELG) sample redshift range $0.6<z<1.7$, that would be suitable for future BAO studies, providing highly biased sample. analyse angular clustering selections redshifts 0.5, 0.7, 0.8, 1 and 1.2 we combine this analysis with halo occupation distribution...
A new fully non-linear reconstruction algorithm for the accurate recovery of Baryonic Acoustic Oscillations (BAO) scale in two-point correlation functions is proposed, based on least-action principle and extending Fast Action Minimisation method by Nusser & Branchini (2000). Especially designed massive spectroscopic surveys, it tested dark-matter halo catalogues extracted from DEUS-FUR $\Lambda$CDM simulation to trace trajectories up $\sim207,000$ haloes backward-in-time, well beyond...
We develop a Principal Component Analysis aimed at classifying subset of 27 350 spectra galaxies in the range 0.4 < z 1.0 collected by VIMOS Public Extragalactic Redshift Survey (VIPERS). apply an iterative algorithm to simultaneously repair parts affected noise and/or sky residuals, and reconstruct gaps due rest-frame transformation, obtain set orthogonal spectral templates that span diversity galaxy types. By taking three most significant components, we find can describe whole sample...
Context. The characterisation of cosmic voids gives unique information about the large-scale distribution galaxies, their evolution, and thecosmological model.
Galaxy clusters are biased tracers of the underlying matter density field. At very large radii beyond about 10 Mpc/\textit{h}, shear profile shows evidence a second-halo term. This is related to correlated distribution around galaxy and proportional so-called halo bias. We present an observational analysis bias-mass relation based on AMICO cluster catalog, comprising 7000 candidates detected in third release KiDS survey. split sample into 14 redshift-richness bins derive bias virial mass...
Aims. We measure far-infrared (FIR) emission from tails of stripped dust following the ionised and atomic gas components in galaxies undergoing ram pressure stripping. study dust-to-gas relative distribution mass ratio interstellar medium relate them to those intra-cluster (ICM), thus linking cluster-ICM-galaxy evolution at small-scales. The galaxy sample consists three Scd Virgo with stellar masses range 10 9 ≲ M * ⊙ within 1 Mpc cluster centre, namely NGC 4330, 4522, 4654. Methods. Through...
Can local fluctuations of a ``quintessence'' scalar field play dynamical role in the gravitational clustering and cosmic structure formation process? We address this question general framework scalar-tensor theories gravity. Nonlinear energy density perturbations, both matter component, linear metric perturbations are accounted for perturbed Einstein equations. derive Newtonian limit relevant equations cosmologies. then specialize to nonlinear ``extended quintessence'' model dark energy;...
We investigate the higher-order correlation properties of VIMOS Public Extragalactic Redshift Survey (VIPERS) to test hierarchical scaling hypothesis at z~1 and dependence on galaxy luminosity, stellar mass, redshift. also aim assess deviations from linearity bias independently a previously performed analysis our survey (Di Porto et al. 2014). have measured count probability distribution function in cells radii 3 < R 10 Mpc/h, deriving $\sigma_{8g}$, volume-averaged two-,three-,and...
Non-linear gravitational clustering in a universe dominated by dark energy, modelled `quintessence' scalar field, and cold matter with spacetime varying mass is studied. Models of this type, where the variable induced dependence on as suggested string theory or extra dimensions, have been proposed viable solution coincidence problem. A general framework for study non-linear phases structure formation field cosmologies provided, starting from relativistic treatment combined matter–dark energy...
The Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE) is a blind narrow-band Halpha+[NII] imaging survey of the cluster carried out with MegaCam at Canada-French-Hawaii telescope (CFHT). We use new set data extracted from VESTIGE to study impact hostile environment on star formation process down scale HII regions (~ 50 pc). are identified and their parameters measured using HIIphot code sample 114 late-type galaxies spanning wide range in morphological type (Sa-Sd, Im, BCD),...
Baryon acoustic oscillations (BAO) have recently been observed in the distribution of distant galaxies. The height and location BAO peak are strong discriminators cosmological parameters. Here we consider ways which weak gravitational lensing distorts signal. We find two effects that can affect correlation function at percent level but do not significantly impact position measurement sound horizon. turn out to be robust standard rulers.
The evolution of the virial overdensity $\Delta_{\rm vir}$ for $\Lambda$CDM and seven dynamical dark-energy models is investigated in extended spherical collapse model (SCM). Here virialization process naturally achieved by introducing shear rotation instead using theorem. We generalise two approaches proposed literature show that, regardless model, new term can be calibrated on peculiar velocity shell as measured from Einstein-de Sitter simulations. recipes qualitatively reproduce features...