A5081097656- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Radio Astronomy Observations and Technology
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Astronomical Observations and Instrumentation
- Astrophysics and Star Formation Studies
- Planetary Science and Exploration
- Superconducting and THz Device Technology
- Industrial Vision Systems and Defect Detection
- Computational Physics and Python Applications
- Inertial Sensor and Navigation
- Scientific Research and Discoveries
- Machine Learning in Materials Science
- Welding Techniques and Residual Stresses
- Geophysics and Gravity Measurements
University of Groningen
2021-2022
Scuola Normale Superiore
2016-2019
Astronomy and Space
2019
University Niccolò Cusano
2016
Istituto Nazionale di Fisica Nucleare, Sezione di Roma I
2016
Technion – Israel Institute of Technology
2016
Sapienza University of Rome
2014-2015
We introduce a new self-consistent model of galaxy evolution and reionization, ASTRAEUS (semi-numerical rAdiative tranSfer coupling formaTion Reionization in N-body dArk mattEr simUlationS), which couples state-of-the-art simulation with the semi-analytical DELPHI semi-numerical reionization scheme CIFOG. includes all key processes formation (including accretion, mergers, supernova radiative feedback) follows time spatial ionized regions intergalactic medium (IGM). Importantly, it explores...
The 21-cm power spectrum (PS) has been shown to be a powerful discriminant of reionization and cosmic dawn astrophysical parameters. However, the tomographic signal is highly non-Gaussian. Therefore there additional information which wasted if only PS used for parameter recovery. Here we showcase recovery directly from images, using deep learning with convolutional neural networks (CNN). Using database 2D images taken 10,000 lightcones (each generated different cosmological initial...
In this work, we have implemented a detailed physical model of galaxy chemical enrichment into the ${\it Astraeus}$ (semi-numerical rAdiative tranSfer coupling formaTion and Reionization in N-body dark matter simUlationS) framework which couples formation reionization first billion years. Simulating galaxies spanning over 2.5 orders magnitude halo mass with $M_h \sim 10^{8.9-11.5} M_\odot$ ($M_h 10^{8.9-12.8} M_\odot$) at $z 10 ~ (5)$, find: (i) smooth-accretion metal-poor gas from...
ABSTRACT Next-generation telescopes such as the James Webb Space Telescope (JWST) and Nancy Grace Roman (NGRST) will enable us to study first billion years of our Universe in unprecedented detail. In this work, we use astraeus (semi-numerical rAdiative tranSfer coupling galaxy formaTion Reionization N-body dArk mattEr simUlationS) framework, which couples formation reionization (for a wide range feedback models), estimate cosmic variance expected UV Luminosity Function (UV LF) stellar mass...
We use the \textsc{astraeus} framework, that couples an N-body simulation with a semi-analytic model for galaxy formation and semi-numerical reionization, to quantify star histories (SFHs) of galaxies in first billion years. Exploring four models radiative feedback, we fit SFH each at $z>5$ as $\mathrm{log}(\mathrm{SFR}(z))=-\alpha(1 + z)+\beta$; is deemed stochastic if it deviates from this by more than $\Delta_\mathrm{SFR}=0.6\,$dex. Our key findings are: (i) The fraction stellar mass...
We present a new approach based on Supervised Machine Learning (SML) algorithms to infer key physical properties of galaxies (density, metallicity, column density and ionization parameter) from their emission line spectra. introduce numerical code (called GAME, GAlaxy learning for Emission lines) implementing this method test it extensively. GAME delivers excellent predictive performances, especially estimates metallicity densities. compare with the most widely used diagnostics (e.g....
We present an updated, optimized version of GAME (GAlaxy Machine learning for Emission lines), a code designed to infer key interstellar medium physical properties from emission line intensities UV/optical/far infrared galaxy spectra. The improvements concern: (a) enlarged spectral library including Pop III stars; (b) the inclusion noise in training procedure, and (c) accurate evaluation uncertainties. extensively validate compare its performance against empirical methods other available...
Dwarf galaxies are ideal laboratories to study the physics of interstellar medium (ISM). Emission lines have been widely used this aim. Retrieving full information encoded in spectra is therefore essential. This can be efficiently and reliably done using Machine Learning (ml) algorithms. Here, we apply ml code game MUSE (Multi Unit Spectroscopic Explorer) PMAS (Potsdam Multi Aperture Spectrophotometer) integral field unit observations two nearby blue compact galaxies: Henize 2-10 IZw18. We...
In this paper we review all the up-to-date Ultra High Energy Cosmic Ray (UHECR) events reported by AUGER, Telescope Array (TA) and AGASA in common coordinate maps. We also confirm our earliest (2008–2013) model, where UHECRs mostly comprise light nuclei (namely He, Be, B), which explains Virgo absence confirms M82 as main source for Northern TA Hot Spot. Many more sources, such NGC253 several galactic are possible candidates most of 376 UHECR events. Several correlated maps, already...
High Energy Neutrino Astronomy has been revealed by a sudden change in the flavor composition above 30 TeV since 2013 IceCube detector: fast growth of spherical showers over atmospheric muon track signal marked revolution.However these discover didn't led to promised Neutrino-Astronomy-Land yet.AGN flaring are not correlated with high energy tens TeV-PeV events.Brightest persistent or pulsed galactic sources missing while no point source arise lower sky.GRB events do correlate within any...
The variabile star Delta Scorpii is in conjunction with the Sun at end of November each year. We studied its magnitude by averaging observations 28 Nov - 1 Dec from 1996 to 2013 using coronograph LASCO C3 on-board SOHO Satellite and we extended four years, i.e. 25 % total light curve, back 1996, respect present AAVSO dataset on this star. 0.2 scatters single measurements have been sources such disturbances are vignetting diffraction patterns coronograph. new data collected show minimum...
In this work, we have implemented a detailed physical model of galaxy chemical enrichment into the ${\it Astraeus}$ (semi-numerical rAdiative tranSfer coupling formaTion and Reionization in N-body dark matter simUlationS) framework which couples formation reionization first billion years. Simulating galaxies spanning over 2.5 orders magnitude halo mass with $M_h \sim 10^{8.9-11.5} M_\odot$ ($M_h 10^{8.9-12.8} M_\odot$) at $z 10 ~ (5)$, find: (i) smooth-accretion metal-poor gas from...
High Energy Neutrino Astronomy has been revealed by a sudden change in the flavor composition around maximal energies since three years of recording ice km detector. However these discover didn' t led to any clear promised land yet. No correlation with hard gamma sources was found. Moreover astrophysical spectra expected at Fermi value, seem converge softer also required avoid Glashow resonant neutrino signal. We suggest main solution within composite flux ruled prompt atmospheric neutrinos....
This white paper highlights the crucial and urgent synergies required between WFIRST, Subaru Hyper Suprime-Cam or other >25m-class telescopes galaxy observations SKA 21cm measurements to constrain nature of reionization (ionization history topology) its sources.