A5004341325- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Radio Astronomy Observations and Technology
- Cosmology and Gravitation Theories
- Scientific Research and Discoveries
- Dark Matter and Cosmic Phenomena
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Astrophysics and Star Formation Studies
- Adaptive optics and wavefront sensing
- Statistical and numerical algorithms
- Gamma-ray bursts and supernovae
- Superconducting and THz Device Technology
- Real-time simulation and control systems
- Calibration and Measurement Techniques
- Remote Sensing and LiDAR Applications
- Earth Systems and Cosmic Evolution
- Relativity and Gravitational Theory
- Advanced Data Storage Technologies
- Particle physics theoretical and experimental studies
- Antenna Design and Optimization
- Space Technology and Applications
- Advanced MRI Techniques and Applications
- Space Science and Extraterrestrial Life
- Advanced Numerical Analysis Techniques
Netherlands Institute for Radio Astronomy
2024-2025
University of Cambridge
2020-2025
Scuola Internazionale Superiore di Studi Avanzati
2024
Institute for Fundamental Physics of the Universe
2024
Cavendish Hospital
2022
University of Washington
2016-2021
Seattle University
2016-2018
The Abdus Salam International Centre for Theoretical Physics (ICTP)
2014-2017
Institute for Advanced Study
2017
University of Ljubljana
2011-2013
We present new measurements of the free-streaming warm dark matter (WDM) from Lyman-$\alpha$ flux-power spectra. use data medium resolution, intermediate redshift XQ-100 sample observed with X-shooter spectrograph ($z=3 - 4.2$) and high-resolution, high-redshift used in Viel et al. (2013) obtained HIRES/MIKE spectrographs ($z=4.2 5.4$). Based on further improved modelling dependence spectrum matter, cosmological parameters, as well thermal history intergalactic (IGM) hydrodynamical...
We present constraints on the masses of extremely light bosons dubbed fuzzy dark matter (FDM) from Lyman-α forest data. Extremely with a de Broglie wavelength ∼1 kpc have been suggested as candidates that may resolve some current small scale problems cold model. For first time, we use hydrodynamical simulations to model flux power spectrum in these models and compare it observed two different data sets: XQ-100 HIRES/MIKE quasar spectra samples. After marginalization over nuisance physical...
We use the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 9 (DR9) to detect and measure position of Baryonic Acoustic (BAO) feature in three-dimensional correlation function Lyman-α flux fluctuations at a redshift zeff = 2.4. The is clearly detected significance between 3 5 sigma (depending on broadband model method error covariance matrix estimation) consistent with predictions standard ΛCDM model. assess biases our method, stability possible systematic effects. fit resulting...
We investigate constraints on scalar dark matter (DM) by analyzing the Lyman-$\ensuremath{\alpha}$ forest, which probes structure formation at medium and small scales, also studying its cosmological consequences high low redshift. For DM that constitutes more than 30% of total density, we obtain a lower limit $m\ensuremath{\gtrsim}{10}^{\ensuremath{-}21}\text{ }\text{ }\mathrm{eV}$ for mass DM. This implies an upper initial field displacement (or decay constant axion-like field)...
We present cosmological results from the measurement of baryon acoustic oscillations (BAO) in galaxy, quasar and Lyman-$\alpha$ forest tracers first year observations Dark Energy Spectroscopic Instrument (DESI), to be released DESI Data Release 1. BAO provide robust measurements transverse comoving distance Hubble rate, or their combination, relative sound horizon, seven redshift bins over 6 million extragalactic objects range $0.1<z<4.2$. data alone are consistent with standard flat...
Abstract We present the measurement of Baryon Acoustic Oscillations (BAO) from Lyman- α (Ly ) forest high-redshift quasars with first-year dataset Dark Energy Spectroscopic Instrument (DESI). Our analysis uses over 420 000 Ly spectra and their correlation spatial distribution more than 700 quasars. An essential facet this work is development a new methodology on blinded dataset. conducted rigorous tests using synthetic data to ensure reliability our findings before unblinding. Additionally,...
We present the DESI 2024 galaxy and quasar baryon acoustic oscillations (BAO) measurements using over 5.7 million unique redshifts in range 0.1<z<2.1. Divided by tracer type, we utilize 300,017 galaxies from magnitude-limited Bright Galaxy Survey with 0.1<z<0.4, 2,138,600 Luminous Red Galaxies 0.4<z<1.1, 2,432,022 Emission Line 0.8<z<1.6, 856,652 quasars 0.8<z<2.1, a ~7,500 square degree footprint. The analysis was blinded at catalog-level to avoid confirmation bias. All fiducial choices of...
This study introduces novel constraints on the free streaming of thermal relic warm dark matter (WDM) from Lyman-<a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>α</a:mi></a:math> forest flux power spectra. Our analysis utilizes a high resolution, redshift sample quasar spectra observed using HIRES and UVES spectrographs (<c:math xmlns:c="http://www.w3.org/1998/Math/MathML"...
ABSTRACT The 1D power spectrum P1D of the Ly α forest provides important information about cosmological and astrophysical parameters, including constraints on warm dark matter models, sum masses three neutrino species, thermal state intergalactic medium. We present first measurement with quadratic maximum likelihood estimator (QMLE) from Dark Energy Spectroscopic Instrument (DESI) survey early data sample. This sample 54 600 quasars is already comparable in size to largest previous studies,...
Abstract We present the DESI 2024 galaxy and quasar baryon acoustic oscillations (BAO) measurements using over 5.7 million unique redshifts in range 0.1 < z 2.1. Divided by tracer type, we utilize 300,017 galaxies from magnitude-limited Bright Galaxy Survey with 0.4, 2,138,600 Luminous Red Galaxies 0.4 1.1, 2,432,022 Emission Line 0.8 1.6, 856,652 quasars 2.1, a ∼ 7,500 square degree footprint. The analysis was blinded at catalog-level to avoid confirmation bias. All fiducial choices of...
Fuzzy Dark Matter (FDM) represents an alternative and intriguing description of the standard Cold fluid, which is able to explain lack direct detection dark matter particles in GeV sector alleviate small-scale tensions cosmic large-scale structure formation. Cosmological simulations FDM models literature were performed either with very expensive high-resolution grid-based individual haloes or through N-body encompassing larger volumes but resorting on significant approximations non-linear...
We compare a sample of five high-resolution, high S/N Ly$\alpha$ forest spectra bright $6<z \lesssim 6.5$ QSOs aimed at spectrally resolving the last remaining transmission spikes $z>5$ with those obtained from mock absorption Sherwood and Sherwood-Relics suites hydrodynamical simulations intergalactic medium (IGM). use profile fitting procedure for inverted transmitted flux, $1-F$, similar to widely used Voigt flux $F$ lower redshifts, characterise that probe predominately underdense...
ABSTRACT We measure the mean free path ($\lambda _{\rm mfp,H\, \small {I}}$), photoionization rate ($\langle \Gamma H\, {I}} \rangle$), and neutral fraction f_{\rm \rangle$) of hydrogen in 12 redshift bins at 4.85 &lt; z 6.05 from a large sample moderate resolution XShooter ESI QSO absorption spectra. The fluctuations ionizing radiation field are modelled by post-processing simulations Sherwood suite using our new code ‘EXtended reionization based on Code for Ionization Temperature...
Current cosmological data exhibit discordance between indirect and some direct inferences of the present-day expansion rate H_{0}. Early dark energy (EDE), which briefly increases cosmic prior to recombination, is a leading scenario for resolving this "Hubble tension" while preserving good fit microwave background (CMB) data. However, comes at cost changes in parameters that affect structure formation late-time universe, including spectral index scalar perturbations n_{s}. Here, we present...
ABSTRACT We present the one-dimensional Ly α forest power spectrum measurement using first data provided by Dark Energy Spectroscopic Instrument (DESI). The sample comprises 26 330 quasar spectra, at redshift z &gt; 2.1, contained in DESI Early Data Release and 2 months of main survey. employ a Fast Fourier Transform (FFT) estimator compare resulting to an alternative likelihood-based method companion paper. investigate methodological instrumental contaminants associated with new...
Abstract Synthetic data sets are used in cosmology to test analysis procedures, verify that systematic errors well understood and demonstrate measurements unbiased. In this work we describe the methods generate synthetic datasets of Lyman-α quasar spectra aimed for studies with Dark Energy Spectroscopic Instrument (DESI). particular, focus on demonstrating our simulations reproduces important features real samples, making them suitable be DESI place limits effects Baryon Acoustic...
We present the Lyman α flux power spectrum measurements of XQ-100 sample quasar spectra obtained in context European Southern Observatory Large Programme 'Quasars and their absorption lines: a legacy survey high redshift universe with VLT/XSHOOTER'. Using 100 medium resolution signal-to-noise ratio, we measure over range redshifts z = 3–4.2 scales k 0.003–0.06 km−1 s. The results agree well one-dimensional found literature. data analysis used this paper is based on Fourier transform has been...
In this paper we present an efficient method for constraining both thermal and non-thermal Dark Matter (DM) scenarios with the Lyman-$\alpha$ forest, based on a simple flexible parametrisation capable to reproduce small scale clustering signal of large set non-cold DM (nCDM) models. We extract new limits fundamental properties, through extensive analysis high resolution, redshift data obtained by MIKE/HIRES spectrographs. By using suite hydrodynamical simulations, determine constraints...
ABSTRACT We present the Sherwood–Relics simulations, a new suite of large cosmological hydrodynamical simulations aimed at modelling intergalactic medium (IGM) during and after cosmic reionization hydrogen. The consists over 200 that cover wide range astrophysical parameters. It also includes use lightweight hybrid scheme for treating radiative transfer effects. This follows spatial variations in ionizing radiation field, as well associated fluctuations IGM temperature pressure smoothing. is...
The last decade has seen unprecedented effort in dark matter model building at all mass scales coupled with the design of numerous new detection strategies. Transformative advances quantum technologies have led to a plethora high-precision sensors and strategies for ultralight ($<10\,$eV) bosonic that can be described by an oscillating classical, largely coherent field. This white paper focuses on searches wavelike scalar vector candidates.
The Cosmology and Astrophysics with MachinE Learning Simulations (CAMELS) project was developed to combine cosmology astrophysics through thousands of cosmological hydrodynamic simulations machine learning. CAMELS contains 4,233 simulations, 2,049 N-body 2,184 state-of-the-art that sample a vast volume in parameter space. In this paper we present the public data release, describing characteristics variety products generated from them, including halo, subhalo, galaxy, void catalogues, power...
Abstract We present the first measurements of Lyman- α (Ly ) forest correlations using early data from Dark Energy Spectroscopic Instrument (DESI). measure auto-correlation Ly absorption 88 509 quasars at z > 2, and its cross-correlation with a further 147 899 tracer ≳ 1.77. Then, we fit these 13-parameter model based on linear perturbation theory find that it provides good description across broad range scales. detect BAO peak signal-to-noise ratio 3.8 σ , show our auto-...
ABSTRACT We measure the three-dimensional power spectrum (P3D) of transmitted flux in Lyman-$\alpha$ (Ly $\alpha$) forest using complete extended Baryon Oscillation Spectroscopic Survey data release 16 (eBOSS DR16). This sample consists $\sim$205 000 quasar spectra redshift range $2\le z \le 4$ at an effective $z=2.334$. propose a pair-count spectral estimator configuration space, weighting each pair by $\exp (i\mathbf {k}\cdot \mathbf {r})$, for wave vector $\mathbf {k}$ and pixel...