A5035010571- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Cosmology and Gravitation Theories
- Radio Astronomy Observations and Technology
- Stellar, planetary, and galactic studies
- Scientific Research and Discoveries
- Pulsars and Gravitational Waves Research
- Adaptive optics and wavefront sensing
- Dark Matter and Cosmic Phenomena
- Astrophysics and Cosmic Phenomena
- History and Developments in Astronomy
- Black Holes and Theoretical Physics
- Calibration and Measurement Techniques
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Spectroscopy and Chemometric Analyses
- Solar and Space Plasma Dynamics
- Particle physics theoretical and experimental studies
- Structural Health Monitoring Techniques
- Remote Sensing in Agriculture
- Gamma-ray bursts and supernovae
- Atmospheric Ozone and Climate
Ohio University
2023-2024
Universitat de Barcelona
2019-2021
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 Baryon acoustic oscillations (BAO) provide a robust standard ruler to measure the expansion history of Universe through galaxy clustering. Density-field reconstruction is now widely adopted procedure for increasing precision and accuracy BAO detection. With goal finding optimal settings be used in DESI 2024 analysis, we assess sensitivity post-reconstruction constraints different choices our analysis configuration, performing tests on blinded data from first year observations (DR1),...
Abstract When measuring the Baryon Acoustic Oscillations (BAO) scale from galaxy surveys, one typically assumes a fiducial cosmology when converting redshift measurements into comoving distances and also defining input parameters for reconstruction algorithm. A parameterised template model to be fitted is created based on (possibly different) cosmology. This reliance can considered form of data compression, then analysed allowing that true answer different assumed. In this study, we evaluate...
The authors introduce a new actor in the current drama of Hubble tension (conflicting measurements ${H}_{0}$), namely age Universe ${t}_{\text{U}}$, as determined by oldest globular clusters, and show that if local are correct, resolution implies modification cosmological standard model $\mathrm{\ensuremath{\Lambda}}$CDM early late Universe. Once systematic uncertainties reduced, measuring ${t}_{\text{U}}$ will discriminate between viable solutions for ${H}_{0}$ tension, i.e. changing or...
ABSTRACT We present the first detection of baryon acoustic oscillations (BAOs) signal obtained using unblinded data collected during initial 2 months operations Stage-IV ground-based Dark Energy Spectroscopic Instrument (DESI). From a selected sample 261 291 luminous red galaxies spanning redshift interval 0.4 < z 1.1 and covering 1651 square degrees with 57.9 per cent completeness level, we report ∼5σ level BAO measurement location at precision 1.7 cent. Using bright galaxy 109 523...
The dominant systematic uncertainty in the age determination of galactic globular clusters is depth convection envelope stars. This parameter partially degenerate with metallicity which turn age. However, if metal content, distance and extinction are known, position morphology red giant branch a color-magnitude diagram mostly sensitive to value convective envelope. Therefore, using external, precise determinations this degeneracy thus error age, can be reduced. Alternatively, color magnitude...
ABSTRACT We present an extended validation of semi-analytical, semi-empirical covariance matrices for the two-point correlation function (2PCF) on simulated catalogs representative luminous red galaxies (LRGs) data collected during initial 2 months operations Stage-IV ground-based Dark Energy Spectroscopic Instrument (DESI). run pipeline multiple effective Zel’dovich (EZ) mock galaxy with corresponding cuts applied and compare results sample to assess accuracy its fluctuations. propose...
Baryon acoustic oscillations (BAO) provide a robust standard ruler to measure the expansion history of Universe through galaxy clustering. Density-field reconstruction is now widely adopted procedure for increasing precision and accuracy BAO detection. With goal finding optimal settings be used in DESI 2024 analysis, we assess sensitivity post-reconstruction constraints different choices our analysis configuration, performing tests on blinded data from first year observations (DR1), as well...
We present an estimate of the absolute age 68 galactic globular clusters obtained by exploiting distribution stars in full color-magnitude diagram. In particular, we jointly age, distance, reddening, metallicity ([Fe/H]) and [α/Fe] each cluster, imposing priors motivated independent observations; also possible systematics from stellar modeling. Our derived distances for cluster sample are agreement with those GAIA using main-sequence dwarf (where available), inferred ages good previously...
We study the clustering properties of dark matter haloes in real- and redshift-space cosmologies with massless massive neutrinos through a large set state-of-the-art N-body simulations. provide quick easy-to-use prescriptions for halo bias on linear mildly non-linear scales, both real redshift-space, which are valid also cosmologies. Finally we present emulator, BE-HaPPY, calibrated simulations, is fast enough to be used standard Markov Chain Monte Carlo approach cosmological inference. For...
We present an extended validation of semi-analytical, semi-empirical covariance matrices for the two-point correlation function (2PCF) on simulated catalogs representative Luminous Red Galaxies (LRG) data collected during initial two months operations Stage-IV ground-based Dark Energy Spectroscopic Instrument (DESI). run pipeline multiple effective Zel'dovich (EZ) mock galaxy with corresponding cuts applied and compare results sample to assess accuracy its fluctuations. propose extension...