J. Aguilar
A5053818740- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Cosmology and Gravitation Theories
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Radio Astronomy Observations and Technology
- Scientific Research and Discoveries
- Dark Matter and Cosmic Phenomena
- Astrophysics and Cosmic Phenomena
- CCD and CMOS Imaging Sensors
- Neutrino Physics Research
- Astronomical Observations and Instrumentation
- Particle Detector Development and Performance
- Superconducting and THz Device Technology
- Astrophysics and Star Formation Studies
- Statistical and numerical algorithms
- Particle physics theoretical and experimental studies
- Radiation Detection and Scintillator Technologies
- Astrophysical Phenomena and Observations
- Remote Sensing in Agriculture
- Calibration and Measurement Techniques
- Advanced Statistical Methods and Models
- Pulsars and Gravitational Waves Research
- Impact of Light on Environment and Health
Lawrence Berkeley National Laboratory
2018-2025
University of Portsmouth
2023
The Dark Energy Spectroscopic Instrument (DESI) has embarked on an ambitious five-year survey to explore the nature of dark energy with spectroscopy 40 million galaxies and quasars. DESI will determine precise redshifts employ Baryon Acoustic Oscillation method measure distances from nearby universe z > 3.5, as well growth structure probe potential modifications general relativity. In this paper we describe significant instrumentation developed for survey. new includes a wide-field, 3.2-deg...
Abstract The Dark Energy Spectroscopic Instrument (DESI) is carrying out a five-year survey that aims to measure the redshifts of tens millions galaxies and quasars, including 8 million luminous red (LRGs) in redshift range 0.4 < z ≲ 1.0. Here we present selection DESI LRG sample assess its spectroscopic performance using data from Survey Validation (SV) first two months Main Survey. sample, selected g , r W 1 photometry Legacy Imaging Surveys, highly robust against imaging systematics....
Abstract The Dark Energy Spectroscopic Instrument (DESI) completed its 5 month Survey Validation in 2021 May. Spectra of stellar and extragalactic targets from constitute the first major data sample DESI survey. This paper describes public release those spectra, catalogs derived properties, intermediate products. In total, includes good-quality spectral information 466,447 objects targeted as part Milky Way Survey, 428,758 Bright Galaxy 227,318 Luminous Red sample, 437,664 Emission Line...
The Dark Energy Spectroscopic Instrument (DESI) was designed to conduct a survey covering 14,000 deg$^2$ over five years constrain the cosmic expansion history through precise measurements of Baryon Acoustic Oscillations (BAO). scientific program for DESI evaluated during month Survey Validation (SV) campaign before beginning full operations. This produced deep spectra tens thousands objects from each stellar (MWS), bright galaxy (BGS), luminous red (LRG), emission line (ELG), and quasar...
Abstract A system of 5020 robotic fiber positioners was installed in 2019 on the Mayall Telescope, at Kitt Peak National Observatory. The robots automatically retarget their optical fibers every 10–20 minutes, each to a precision several microns, with reconfiguration time fewer than 2 minutes. Over next 5 yr, they will enable newly constructed Dark Energy Spectroscopic Instrument (DESI) measure spectra 35 million galaxies and quasars. DESI produce largest 3D map universe date expansion...
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 describe the Milky Way Survey (MWS) that will be undertaken with Dark Energy Spectroscopic Instrument (DESI) on Mayall 4m telescope at Kitt Peak National Observatory. Over next 5 yr DESI MWS observe approximately seven million stars Galactic latitudes |b|>20 degrees, an inclusive target selection scheme focused thick disk and stellar halo. also include several high-completeness samples of rare types, including white dwarfs, low-mass within 100pc Sun, horizontal branch stars. summarize...
The Dark Energy Spectroscopic Instrument (DESI) completed its five-month Survey Validation in May 2021. Spectra of stellar and extragalactic targets from constitute the first major data sample DESI survey. This paper describes public release those spectra, catalogs derived properties, intermediate products. In total, includes good-quality spectral information 466,447 objects targeted as part Milky Way Survey, 428,758 Bright Galaxy 227,318 Luminous Red sample, 437,664 Emission Line 76,079...
Abstract A key component of the Dark Energy Spectroscopic Instrument (DESI) survey validation (SV) is a detailed visual inspection (VI) optical spectroscopic data to quantify metrics. In this paper we present results from VI quasar using deep coadded SV spectra. We show that majority (≈70%) main-survey targets are spectroscopically confirmed as quasars, with ≈16% galaxies, ≈6% stars, and ≈8% low-quality spectra lacking reliable features. nonnegligible fraction quasars misidentified by...
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...
Abstract The Dark Energy Spectroscopic Instrument (DESI) is currently measuring the spectra of 40 million galaxies and quasars, largest such survey ever made to probe nature cosmological dark energy. 4 m Mayall telescope at Kitt Peak National Observatory has been adapted for DESI, including construction a 3.°2 diameter prime focus corrector that focuses astronomical light onto 0.8 focal surface with excellent image quality over DESI bandpass 360–980 nm. wide-field includes six lenses, as...
ABSTRACT We present the first comprehensive halo occupation distribution (HOD) analysis of Dark Energy Spectroscopic Instrument (DESI) One-Percent Survey luminous red galaxy (LRG) and Quasi Stellar Object (QSO) samples. constrain HOD each sample test possible extensions by fitting redshift-space 2-point correlation functions in 0.15 &lt; r 32 h−1 Mpc a set fiducial redshift bins. use AbacusSummit cubic boxes at Planck 2018 cosmology as model templates forward clustering with AbacusHOD...
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 This paper provides a comprehensive overview of how fitting baryon acoustic oscillations (BAO) is carried out within the upcoming Dark Energy Spectroscopic Instrument’s (DESI) 2024 results using its DR1 data set, and associated systematic error budget from theory modelling BAO. We derive new showing non-linearities in clustering galaxies can cause potential biases measurements isotropic ($\alpha _{\mathrm{iso}}$) anisotropic _{\mathrm{ap}}$) BAO distance scales, these be effectively...
Abstract Changing-look active galactic nuclei (CL AGNs) can be generally confirmed by the emergence (turn-on) or disappearance (turn-off) of broad emission lines (BELs), associated with a transient timescale (about 100 ∼ 5000 days) that is much shorter than predicted traditional accretion disk models. We carry out systematic CL AGN search crossmatching spectra coming from Dark Energy Spectroscopic Instrument and Sloan Digital Sky Survey. Following previous studies, we identify AGNs based on...
Abstract We present an optimized way of producing the fast semi-analytical covariance matrices for Legendre moments two-point correlation function, taking into account survey geometry and mimicking non-Gaussian effects. validate approach on simulated (mock) catalogs different galaxy types, representative Dark Energy Spectroscopic Instrument (DESI) Data Release 1, used in 2024 analyses. find only a few percent differences between mock sample matrix our results, which can be expected given...
Abstract We present the technical details on how large-scale structure (LSS) catalogs are constructed from redshifts measured spectra observed by Dark Energy Spectroscopic Instrument (DESI). The LSS provide information needed to determine relative number density of DESI tracers as a function redshift and celestial coordinates and, e.g., clustering statistics. produce that weighted subsamples data, each matched `random' catalog forms an unclustered sampling probability could have those data...
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...
Abstract Dark Energy Spectroscopic Instrument (DESI) uses more than 2.4 million Emission Line Galaxies (ELGs) for 3D large-scale structure (LSS) analyses in its Data Release 1 (DR1). Such large statistics enable thorough research on systematic uncertainties. In this study, we focus spectroscopic systematics of ELGs. The redshift success rate ( f goodz ) is the relative fraction secure redshifts among all measurements. It depends observing conditions, thus introduces non-cosmological...
Abstract The Dark Energy Spectroscopic Instrument (DESI) will provide precise measurements of Baryon Acoustic Oscillations (BAO) to constrain the expansion history Universe and set stringent constraints on dark energy. Therefore, control global error budget due various systematic effects is required for DESI 2024 BAO analysis. In this work, we estimate level systematics induced in analysis assumed Halo Occupation Distribution (HOD) model Emission Line Galaxy (ELG) tracer. We make use mock...
Abstract In this paper, we present the estimation of systematics related to halo occupation distribution (HOD) modeling in baryon acoustic oscillations (BAO) distance measurement Dark Energy Spectroscopic Instrument (DESI) 2024 analysis. This paper focuses on study HOD for luminous red galaxies (LRG). We consider three different models LRGs, including base 5-parameter vanilla model and two extensions it, that refer as baseline extended models. The is described by 5 parameters, an...
Abstract Baryon Acoustic Oscillations can be measured with sub-percent precision above redshift two the Lyman- α (Ly ) forest auto-correlation and its cross-correlation quasar positions. This is one of key goals Dark Energy Spectroscopic Instrument (DESI) which started main survey in May 2021. We present this paper a study contaminants to Ly are mainly caused by correlated signals introduced spectroscopic data processing pipeline as well astrophysical due foreground absorption intergalactic...
Abstract The large scale structure catalogs within DESI Data Release 1 (DR1) use nearly 6 million galaxies and quasars as tracers of the large-scale universe to measure expansion history with baryon acoustic oscillations growth redshift-space distortions. In order take advantage DESI's unprecedented statistical power, we must ensure that galaxy clustering measurements are unaffected by non-cosmological density fluctuations. One source spurious fluctuations comes from variation in...
Abstract In the era of precision cosmology, ensuring integrity data analysis through blinding techniques is paramount — a challenge particularly relevant for Dark Energy Spectroscopic Instrument (DESI). DESI represents monumental effort to map cosmic web, with goal measure redshifts tens millions galaxies and quasars. Given volume impact findings, potential confirmation bias poses significant challenge. To address this, we implement validate comprehensive blind strategy Data Release 1 (DR1),...
The determination of the direction a stellar core collapse via its neutrino emission is crucial for identification progenitor multimessenger follow-up. A highly effective method reconstructing supernova directions within Deep Underground Neutrino Experiment (DUNE) introduced. pointing resolution studied by simulating and electron-neutrino charged-current absorption on <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"...