Giulio Fabbian
A5086473944- Cosmology and Gravitation Theories
- Radio Astronomy Observations and Technology
- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Superconducting and THz Device Technology
- Dark Matter and Cosmic Phenomena
- Geophysics and Gravity Measurements
- Astrophysics and Cosmic Phenomena
- Adaptive optics and wavefront sensing
- Computational Physics and Python Applications
- Scientific Research and Discoveries
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Gamma-ray bursts and supernovae
- History and Developments in Astronomy
- Simulation Techniques and Applications
- Distributed and Parallel Computing Systems
- Precipitation Measurement and Analysis
- Pulsars and Gravitational Waves Research
- Relativity and Gravitational Theory
- Neutrino Physics Research
- Impact of Light on Environment and Health
- Solar and Space Plasma Dynamics
- Particle physics theoretical and experimental studies
- Climate variability and models
Cardiff University
2014-2024
Flatiron Health (United States)
2021-2024
Flatiron Institute
2021-2024
Institute of Astronomy
2024
Université Paris-Saclay
2017-2023
Université Paris-Sud
2017-2023
Centre National de la Recherche Scientifique
2012-2023
Institut d'Astrophysique Spatiale
2017-2023
University of Sussex
2019-2022
Computational Physics (United States)
2021
The Simons Observatory (SO) is a new cosmic microwave background experiment being built on Cerro Toco in Chile, due to begin observations the early 2020s. We describe scientific goals of experiment, motivate design, and forecast its performance. SO will measure temperature polarization anisotropy six frequency bands: 27, 39, 93, 145, 225 280 GHz. initial configuration have three small-aperture 0.5-m telescopes (SATs) one large-aperture 6-m telescope (LAT), with total 60,000 cryogenic...
We present the science case, reference design, and project plan for Stage-4 ground-based cosmic microwave background experiment CMB-S4.
This book lays out the scientific goals to be addressed by next-generation ground-based cosmic microwave background experiment, CMB-S4, envisioned consist of dedicated telescopes at South Pole, high Chilean Atacama plateau and possibly a northern hemisphere site, all equipped with new superconducting cameras. CMB-S4 will dramatically advance cosmological studies crossing critical thresholds in search for B-mode polarization signature primordial gravitational waves, determination number...
The Euclid space telescope will measure the shapes and redshifts of galaxies to reconstruct expansion history Universe growth cosmic structures. Estimation expected performance experiment, in terms predicted constraints on cosmological parameters, has so far relied different methodologies numerical implementations, developed for observational probes their combination. In this paper we present validated forecasts, that combine both theoretical expertise probes. This is presented provide...
We report a measurement of the B-mode polarization power spectrum in cosmic microwave background (CMB) using Polarbear experiment Chile. The faint signature carries information about universe's entire history gravitational structure formation, and inflation that may have occurred very early universe. Our covers angular multipole range 500 < ℓ 2100 is based on observations an effective sky area 25 with 35 resolution at 150 GHz. On these scales, lensing CMB by intervening universe expected to...
Abstract CMB-S4—the next-generation ground-based cosmic microwave background (CMB) experiment—is set to significantly advance the sensitivity of CMB measurements and enhance our understanding origin evolution universe. Among science cases pursued with CMB-S4, quest for detecting primordial gravitational waves is a central driver experimental design. This work details development forecasting framework that includes power-spectrum-based semianalytic projection tool, targeted explicitly toward...
We present a new, updated version of the EuclidEmulator (called EuclidEmulator2), fast and accurate predictor for nonlinear correction matter power spectrum. Percent-level emulation is now supported in eight-dimensional parameter space $w_0w_a$CDM$+\sum m_\nu$models between redshift $z=0$ $z=3$ spatial scales within range 0.01 $h$/Mpc $\leq k \leq$ 10 $h$/Mpc. In order to achieve this level accuracy, we have had improve quality underlying N-body simulations used as training data: (1) use...
Abstract We present a new, all-sky quasar catalog, Quaia, that samples the largest comoving volume of any existing spectroscopic sample. The catalog draws on 6,649,162 candidates identified by Gaia mission have redshift estimates from space observatory’s low-resolution blue photometer/red photometer spectra. This initial sample is highly homogeneous and complete, but has low purity, 18% even bright ( G < 20.0) confirmed quasars discrepant (∣Δ z /(1 + )∣ > 0.2) compared to those Sloan...
Distortion of the cosmic microwave background by matter in universe, known as gravitational lensing, is observed POLARBEAR collaboration. The technique used here would allow for all gravitating to be mapped, and provide important corrections detection primordial waves background.
Abstract We report an improved measurement of the cosmic microwave background B -mode polarization power spectrum with Polarbear experiment at 150 GHz. By adding new data collected during second season observations (2013–2014) to re-analyzed from first (2012–2013), we have reduced twofold band-power uncertainties. The band powers are reported over angular multipoles , where dominant signal is expected be due gravitational lensing E -modes. reject null hypothesis no a confidence 3.1 σ...
We constrain anisotropic cosmic birefringence using four-point correlations of even-parity $E$-mode and odd-parity $B$-mode polarization in the microwave background measurements made by POLARization Background Radiation (POLARBEAR) experiment its first season observations. find that signal from any parity-violating processes is consistent with zero. The Faraday rotation can be compared equivalent quantity generated primordial magnetic fields if they existed. POLARBEAR nondetection translates...
A new technique, first performed using the South Pole Telescope, that allows gravitational deflections of cosmic microwave background to be measured from photon polarization, gets further support measurements by POLARBEAR collaboration.
The Simons Observatory (SO) is a ground-based cosmic microwave background (CMB) experiment sited on Cerro Toco in the Atacama Desert Chile that promises to provide breakthrough discoveries fundamental physics, cosmology, and astrophysics. Supported by Foundation, Heising-Simons with contributions from collaborating institutions, SO will see first light 2021 start five year survey 2022. has 287 collaborators 12 countries 53 including 85 students 90 postdocs. its currently funded form...
Deviations from the blackbody spectral energy distribution of cosmic microwave background (CMB) are a precise probe physical processes active both in early Universe (such as those connected to particle decays and inflation) at later times (e.g., reionization astrophysical emissions). Limited progress has been made characterization these distortions after pioneering measurements FIRAS instrument on COBE satellite 1990s, which mainly targeted measurement their average amplitude across sky....
The upcoming Simons Observatory Small Aperture Telescopes aim at achieving a constraint on the primordial tensor-to-scalar ratio $r$ level of $\sigma(r=0)\lesssim0.003$, observing polarized CMB in presence partial sky coverage, cosmic variance, inhomogeneous non-white noise, and Galactic foregrounds. We present three different analysis pipelines able to constrain given latest available instrument performance, compare their predictions set simulations that allow us explore number foreground...
We present the design and characterization of POLARBEAR experiment. will measure polarization cosmic microwave background (CMB) on angular scales ranging from experiment's 3.5 arcminute beam size to several degrees. The experiment utilizes a unique focal plane 1,274 antenna-coupled, sensitive TES bolometers cooled 250 milliKelvin. Employing this along with stringent control over systematic errors, has sensitivity detect expected small scale B-mode signal due gravitational lensing search for...
Forthcoming large photometric surveys for cosmology require precise and accurate redshift (photo- z ) measurements the success of their main science objectives. However, to date, no method has been able produce photo- s at required accuracy using only broad-band photometry that those will provide. An assessment strengths weaknesses current methods is a crucial step in eventual development an approach meet this challenge. We report on performance 13 code single value estimates probability...
The cross-correlation between cosmic microwave background (CMB) gravitational lensing and large-scale structure tracers will be an important cosmological probe in the coming years. Quadratic estimators provide a simple powerful (if suboptimal) way to reconstruct CMB potential are widely used. For Gaussian fields, of quadratic-estimator reconstruction with tracer is exactly unbiased if power spectra known consistent analytic mode response functions However, bispectrum induced by non-linear...
The Simons Observatory (SO) will make precise temperature and polarization measurements of the cosmic microwave background (CMB) using a set telescopes which cover angular scales between 1 arcminute tens degrees, contain over 60,000 detectors, observe at frequencies 27 270 GHz. SO consist 6 m aperture telescope coupled to 30,000 transition-edge sensor bolometers along with three 42 cm refractive telescopes, an additional 30,000+ all be located in Atacama Desert altitude 5190 m. powerful...
Inflation may provide unique insight into the physics at highest available energy scales that cannot be replicated in any realistic terrestrial experiment. Features primordial power spectrum are generically predicted a wide class of models inflation and its alternatives, observationally one most overlooked channels for finding evidence non-minimal inflationary models. Constraints from observations cosmic microwave background cover widest range feature frequencies, but sensitive constraints...
The combination and cross-correlation of the upcoming $Euclid$ data with cosmic microwave background (CMB) measurements is a source great expectation since it will provide largest lever arm epochs, ranging from recombination to structure formation across entire past light cone. In this work, we present forecasts for joint analysis CMB on cosmological parameters standard model some its extensions. This work expands complements recently published based $Euclid$-specific probes, namely galaxy...
Abstract Cosmic birefringence is the in-vacuo, frequency independent rotation of polarization plane linearly polarized radiation, induced by a parity-violating term in electromagnetic Lagrangian. We implement harmonic estimator for field that only relies on CMB E to B mode cross-correlation, thus suppressing effect cosmic variance from temperature field. derive constraints Planck public releases 3 and 4, revealing power spectrum consistent with zero at about 2 σ up multipole L = 1500....