B. Sartoris
A5075489166- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Cosmology and Gravitation Theories
- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Scientific Research and Discoveries
- Astrophysics and Cosmic Phenomena
- Remote Sensing in Agriculture
- Dark Matter and Cosmic Phenomena
- History and Developments in Astronomy
- Astro and Planetary Science
- Radio Astronomy Observations and Technology
- CCD and CMOS Imaging Sensors
- Astrophysics and Star Formation Studies
- Calibration and Measurement Techniques
- Statistical and numerical algorithms
- Advanced Vision and Imaging
- Spectroscopy and Laser Applications
- Pulsars and Gravitational Waves Research
- Data Visualization and Analytics
- Plant Water Relations and Carbon Dynamics
- Particle physics theoretical and experimental studies
Ludwig-Maximilians-Universität München
2013-2025
Trieste Astronomical Observatory
2015-2025
University College London
2024
University of Copenhagen
2024
Flatiron Health (United States)
2024
Flatiron Institute
2024
Royal Holloway University of London
2024
University of California, Davis
2024
New York University
2024
Princeton University
2024
Euclid is a space-based survey mission from the European Space Agency designed to understand origin of Universe's accelerating expansion. It will use cosmological probes investigate nature dark energy, matter and gravity by tracking their observational signatures on geometry universe cosmic history structure formation. The optimised for two independent primary probes: Weak gravitational Lensing (WL) Baryonic Acoustic Oscillations (BAO). payload consists 1.2 m Korsch telescope provide large...
We study the characteristics of galaxy cluster samples expected from European Space Agency's Euclid satellite and forecast constraints on cosmological parameters describing a variety models. The method used in this paper, based Fisher Matrix approach, is same one to provide presented Red Book (Laureijs et al.2011). describe analytical approach compute selection function photometric spectroscopic surveys. Based function, we number parameter sets corresponding different extensions standard...
We use an unprecedented data-set of about 600 redshifts for cluster members, obtained as part a VLT/VIMOS large programme, to constrain the mass profile z=0.44 MACS J1206.2-0847 over radial range 0-5 Mpc (0-2.5 virial radii) using MAMPOSSt and Caustic methods. then add external constraints from our previous gravitational lensing analysis. invert Jeans equation obtain velocity-anisotropy profiles members. With mass-density we first determination pseudo-phase-space density profile. The...
We report the spectroscopic confirmation of 22 new multiply lensed sources behind Hubble Frontier Field (HFF) galaxy cluster MACS~J0416.1$-$2403 (MACS 0416), using archival data from Multi Unit Spectroscopic Explorer (MUSE) on VLT. Combining with previous measurements 15 other imaged sources, we obtain a sample 102 secure multiple images measured redshifts, largest to date in single strong lensing system. The newly confirmed are largely low-luminosity Lyman-$\alpha$ emitters redshift range...
We perform a comprehensive study of the total mass distribution galaxy cluster RXCJ2248 ($z=0.348$) with set high-precision strong lensing models, which take advantage extensive spectroscopic information on many multiply lensed systems. In effort to understand and quantify inherent systematics in parametric modelling, we explore collection 22 models where use different samples multiple image families, parametrizations cosmological parameters. As input for CLASH HST imaging data follow-up...
We present a detailed mass reconstruction and novel study on the substructure properties in core of Cluster Lensing And Supernova survey with Hubble (CLASH) Frontier Fields galaxy cluster MACS J0416.1−2403. show employ our extensive spectroscopic data set taken VIsible Multi-Object Spectrograph instrument as part CLASH-VLT program, to confirm spectroscopically 10 strong lensing systems select sample 175 plausible members limiting stellar log (M*/M☉) ≃ 8.6. reproduce measured positions 30...
Galaxy cluster counts in bins of mass and redshift have been shown to be a competitive probe test cosmological models. This method requires an efficient blind detection clusters from surveys with well-known selection function robust estimates. The Euclid wide survey will cover 15000 deg$^2$ the sky optical near-infrared bands, down magnitude 24 $H$-band. resulting data make it possible detect large number galaxy spanning wide-range masses up $\sim 2$. paper presents final results Cluster...
The Cluster HEritage project with XMM-Newton - Mass Assembly and Thermodynamics at the Endpoint of structure formation (CHEX-MATE) is a three mega-second Multi-Year Heritage Programme to obtain X-ray observations minimally-biased, signal-to-noise limited sample 118 galaxy clusters detected by Planck through Sunyaev-Zeldovich effect. programme, described in detail this paper, aims study ultimate products time mass. It composed census most recent objects have formed (Tier-1: 0.05 < z 0.2; 2 x...
Aims. We aim constrain the assembly history of clusters by studying intracluster light (ICL) properties, estimating its contribution to fraction baryons in stars, f∗, and understanding possible systematics or bias using different ICL detection techniques.
Context. The analysis of galaxy properties, such as stellar masses, colors, sizes and morphologies, the relations among them environment, in which galaxies reside, can be used to investigate physical processes driving evolution.
We present VIMOS-VLT spectroscopy of the Frontier Fields cluster MACS~J0416.1-2403 (z=0.397). Taken as part CLASH-VLT survey, large spectroscopic campaign provided more than 4000 reliable redshifts, including ~800 member galaxies. The unprecedented sample members at this redshift allows us to perform a highly detailed dynamical and structural analysis out ~2.2$r_{200}$ (~4Mpc). Our substructures reveals complex system composed main massive ($M_{200}$~0.9$\times 10^{15} M_{\odot}$) presenting...
Euclid's photometric galaxy cluster survey has the potential to be a very competitive cosmological probe. The main probe with observations of clusters is their number count, within which halo mass function (HMF) key theoretical quantity. We present new calibration analytic HMF, at level accuracy and precision required for uncertainty in this quantity subdominant respect other sources recovering parameters from Euclid counts. Our model calibrated against suite N-body simulations using...
Aims. We validate a semi-analytical model for the covariance of real-space two-point correlation function galaxy clusters. Methods. Using 1000 PINOCCHIO light cones mimicking expected Euclid sample clusters, we calibrated simple to accurately describe clustering covariance. Then, used this quantify likelihood-analysis response variations in covariance, and investigated impact cosmology-dependent matrix at level statistics survey Results. find that Gaussian with Poissonian shot-noise does not...
Context. The study of the galaxy stellar mass function (SMF) in relation to environment and density profile, rho(r), is a powerful tool constrain models evolution. Aims. We determine SMF z=0.44 cluster galaxies MACS J1206.2-0847 separately for passive star-forming (SF) galaxies, different regions cluster, from center out approximately 2 virial radii. also rho(r) compare it number total profiles. Methods. use dataset CLASH-VLT survey. Stellar masses are obtained by SED fitting on 5-band...
We present the clustering of galaxy clusters as a useful addition to common set cosmological observables. The probes large-scale structure Universe, extending analysis high-peak, high-bias regime. Clustering complements traditional cluster number counts and observable-mass relation analyses, significantly improving their constraining power by breaking existing calibration degeneracies. use maxBCG catalogue constrain parameters cross-calibrate mass-observable relation, using abundances in...
We discuss the reliability of neutrino mass constraints, either active or sterile, from combination different low redshift Universe probes with measurements CMB anisotropies. In our analyses we consider WMAP 9-year Planck Cosmic Microwave Background (CMB) data in Baryonic Acoustic Oscillations (BAO) BOSS DR11, galaxy shear CFHTLenS, SDSS Ly α forest constraints and cluster function Chandra observations. At odds recent similar studies, to avoid model dependence perform a full likelihood...
We present a new strong lensing analysis of the galaxy cluster MACS J1206.2-0847 (MACS 1206), at z=0.44, using deep spectroscopy from CLASH-VLT and VLT/MUSE archival data in combination with imaging Cluster Lensing Supernova survey Hubble. MUSE observations enable spectroscopic identification 23 multiply imaged sources, extending previous compilations by factor approximately five. In total, we use positional measurements 82 multiple images belonging to 27 families z=1.0-6.1 reconstruct...
Aims. In the effort to understand link between structure of galaxy clusters and their populations, we focus on MACS J1206.2-0847 at z ~ 0.44 probe its substructure in projected phase space through spectrophotometric properties a large number galaxies from CLASH-VLT survey.
We report the analysis of Chandra observation XDCP J0044.0-2033, a massive, distant (z=1.579) galaxy cluster discovered in survey. The total exposure time 380 ks with ACIS-S provides deepest X-ray currently achieved on high redshift cluster. Extended emission from Intra Cluster Medium (ICM) is detected at very significance level (S/N~20) circular region 44" radius, corresponding to $R_{ext}=375$ kpc redshift. perform an spectral fit ICM modeling spectrum single-temperature thermal mekal...
Context: The shape of the mass density profiles cosmological halos informs us nature DM and DM-baryons interactions. Previous estimates inner slope clusters galaxies are in opposition to predictions derived from numerical simulations CDM. Aims: We determine profile a massive cluster galaxies, Abell S1063 (RXC J2248.7$-$4431) at $z=0.35$, with dynamical analysis based on an extensive spectroscopic campaign carried out VIMOS MUSE spectrographs ESO VLT. This new data set provides unprecedented...
Using the CLASH-VLT survey, we assembled an unprecedented sample of 1234 spectroscopically confirmed members in Abell~S1063, finding a dynamically complex structure at z_cl=0.3457 with velocity dispersion \sigma_v=1380 -32 +26 km s^-1. We investigate cluster environmental and dynamical effects by analysing projected phase-space diagram orbits as function galaxy spectral properties. classify galaxies according to presence strength [OII] emission line, H$\delta$ absorption colours....
We present forecasts for constraints on deviations from Gaussian distribution of primordial density perturbations future X-ray surveys galaxy clusters. Our analysis is based computing the Fisher-Matrix number counts and large-scale power spectrum consider a survey with high-sensitivity wide-area to detect about 2.5 x 10^5 extended sources. Based self-calibration approach, including Planck priors in our analysis, we constrain 9 cosmological parameters 4 nuisance parameters, which define...
Pair-instability supernovae are theorized that have not yet been observationally confirmed. They predicted to exist in low-metallicity environments. Because overall metallicity becomes lower at higher redshifts, deep near-infrared transient surveys probing high-redshift suitable discover pair-instability supernovae. The Euclid satellite, which is planned be launched 2023, has a wide-field instrument for supernova survey. Deep Survey make regular observations of three Fields (40 deg2 total)...
A pressureless scenario for the dark matter (DM) fluid is a widely adopted hypothesis, despite absence of direct observational evidence. According to general relativity, total mass–energy content system shapes gravitational potential well, but different test particles perceive this in ways depending on their properties. Cluster galaxy velocities, being ≪c, depend solely potential, whereas photon trajectories reflect contributions from plus relativistic-pressure term that depends cluster...