A5066518636- Galaxies: Formation, Evolution, Phenomena
- Cosmology and Gravitation Theories
- Dark Matter and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Astrophysics and Cosmic Phenomena
- Astronomy and Astrophysical Research
- Mechanics and Biomechanics Studies
- International Relations in Latin America
- Black Holes and Theoretical Physics
- Pulsars and Gravitational Waves Research
- Computational Physics and Python Applications
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- CCD and CMOS Imaging Sensors
- Statistical and numerical algorithms
- Conflict, Peace, and Violence in Colombia
- Nuclear Physics and Applications
- Advanced Optical Sensing Technologies
- Remote Sensing and LiDAR Applications
- Gamma-ray bursts and supernovae
- Remote Sensing in Agriculture
- Gaussian Processes and Bayesian Inference
- Relativity and Gravitational Theory
- Advanced X-ray Imaging Techniques
- Sociology, Governance, and Technology
Instituto de Física de Cantabria
2023-2025
Consejo Superior de Investigaciones Científicas
2024
Universidad de Cantabria
2024
Johns Hopkins University
2020-2023
Fundación Instituto para la Mejora de la Asistencia Sanitaria
2022-2023
Max Planck Institute for Astrophysics
2023
Hospital Universitario 12 De Octubre
2022
State Council of the People's Republic of China
2022
Universitat de Barcelona
2016-2021
Institut d'Estudis Espacials de Catalunya
2019
We perform a comprehensive cosmological study of the $H_0$ tension between direct local measurement and model-dependent value inferred from Cosmic Microwave Background. With recent this has raised to more than $3σ$. consider changes in early time physics without modifying late cosmology. also reconstruct expansion history model independent way with minimal assumptions using distances measures Baryon Acoustic Oscillations Type Ia Supernovae, finding that at $z<0.6$ recovered shape is less...
Abstract We present a detailed overview of the cosmological surveys that we aim to carry out with Phase 1 Square Kilometre Array (SKA1) and science they will enable. highlight three main surveys: medium-deep continuum weak lensing low-redshift spectroscopic HI galaxy survey over 5 000 deg 2 ; wide deep intensity mapping (IM) 20 from $z = 0.35$ 3; deep, high-redshift IM 100 3$ 6. Taken together, these achieve an array important scientific goals: measuring equation state dark energy \sim...
Scattering and decay processes of thermal bath particles involving heavy leptons can dump hot axions in the primordial plasma around QCD phase transition. We compute their relic density, parameterized by an effective number ΔNeff additional neutrinos. For couplings allowed current bounds, production via scattering yields ≲ 0.6 0.2 for cases muon tau, respectively. Flavor violating tau decays to a lighter lepton plus axion give 0.3. Such values alleviate tension between direct local...
We revisit the impact of early dark energy (EDE) on galaxy clustering using BOSS power spectra, analyzed effective field theory (EFT) large-scale structure (LSS) and anisotropies cosmic microwave background (CMB) from Planck. Recent studies found that these data place stringent constraints maximum abundance EDE allowed in Universe. argue here their conclusions are a consequence choice priors parameter space, rather than any disagreement between model. For example, when considering EFT-LSS,...
Measurements of weak gravitational lensing at low redshifts ($z\lesssim 0.5-1$), quantified by the parameter $S_8$, favor weaker matter clustering than that expected from standard $\Lambda$CDM cosmological model with parameters determined cosmic microwave background (CMB) measurements. However, amplitude higher redshifts, as probed CMB, is consistent $\Lambda$CDM. This apparent paradox suggests a connection between $S_8$ tension and transition to dark-energy domination. Here we show can be...
The model in which Primordial Black Holes (PBHs) constitute a non-negligible fraction of the dark matter has (re)gained popularity after first detections binary black hole mergers. Most observational constraints to date have been derived assuming single mass for all PBHs, although some more recent works tried generalize case extended functions. Here we derive general methodology obtain any PBH Extended Mass Distribution (EMD) and observables desired range. Starting from those obtained...
Assuming the existence of standard rulers, candles and clocks, requiring only cosmological principle, a metric theory gravity, smooth expansion history using state-of-the-art observations, we determine length 'low-redshift ruler'. The data use are compilation recent baryon acoustic oscillation (relying on ruler), Type Ia supernovae (as candles), ages early-type galaxies clocks) local determinations Hubble constant anchor cosmic distance scale). In Λ cold dark matter cosmology, ruler'...
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...
Line-intensity mapping (LIM) provides a promising way to probe cosmology, reionization and galaxy evolution. However, its sensitivity cosmology astrophysics at the same time is also nuisance. Here we develop comprehensive framework for modelling LIM power spectrum, which includes redshift space distortions Alcock-Paczynski effect. We then identify isolate degeneracies with so that they can be marginalized over. study gains of using multipole expansion anisotropic providing an accurate...
Our current understanding of the Universe is established through pristine measurements structure in cosmic microwave background (CMB) and distribution shapes galaxies tracing large scale (LSS) Universe. One key ingredient that underlies cosmological observables field sources observed assumed to be initially Gaussian with high precision. Nevertheless, a minimal deviation from Gaussianityis perhaps most robust theoretical prediction models explain Universe; itis necessarily present even...
Our current understanding of the Universe is established through pristine measurements structure in cosmic microwave background (CMB) and distribution shapes galaxies tracing large scale (LSS) Universe. One key ingredient that underlies cosmological observables field sources observed assumed to be initially Gaussian with high precision. Nevertheless, a minimal deviation from Gaussianityis perhaps most robust theoretical prediction models explain Universe; itis necessarily present even...
Baryon acoustic oscillations (BAO) provide a robust standard ruler and can be used to constrain the expansion history of Universe at low redshift. Standard BAO analyses return model-independent measurement rate comoving angular diameter distance as function redshift, normalized by sound horizon radiation drag. However, this methodology relies on anisotropic distortions fixed, precomputed template (obtained in given fiducial cosmology) order fit observations. Therefore, it may possible that...
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...
Recent studies using New Horizons's Long Range Reconnaisance Imager (LORRI) images have returned the most precise measurement of cosmic optical background to date, yielding a flux that exceeds expected from deep galaxy counts by roughly factor 2. We investigate whether this excess, detected at ∼4σ significance, is due axionlike dark matter decays monoenergetic photons. compute spectral energy distribution such and contribution measured LORRI. Assuming particles make up all matter, parameter...
The three rung distance ladder, which calibrates Type Ia supernovae through stellar distances linked to geometric measurements, provides the highest precision direct measurement of Hubble constant. In light tension, it is important test individual components ladder. For this purpose, we report a constant from 35 extragalactic Cepheid hosts measured by SH0ES team, using their and redshifts at cz < 3300 km /s , instead any, more distant supernovae, measure flow. are calibrated geometrically in...
Abstract This paper discusses the science case for a sensitive spectro-polarimetric survey of microwave sky. Such would provide tomographic and dynamic census three-dimensional distribution hot gas, velocity flows, early metals, dust, mass in entire Hubble volume, exploit CMB temperature polarisation anisotropies down to fundamental limits, track energy injection absorption into radiation background across cosmic times by measuring spectral distortions blackbody emission. In addition its...
The nature of dark matter is a longstanding mystery in cosmology, which can be studied with laboratory or collider experiments, as well astrophysical and cosmological observations. In this work, we propose realistic efficient strategies to detect radiative products from dark-matter decays line-intensity mapping (LIM) experiments. This radiation will behave line interloper for the atomic molecular spectral lines targeted by LIM surveys. most distinctive signatures contribution are an extra...
The flux of high-energy astrophysical $\gamma$ rays is attenuated by the production electron-positron pairs from scattering off extragalactic background light (EBL). We use most up-to-date information on galaxy populations to compute their contributions pair-production optical depth. find that depth inferred $\gamma$-ray measurements exceeds expected galaxies at $\sim2\sigma$ level. If excess modeled as a frequency-independent re-scaling standard contribution EBL galaxies, then an (an...
Line-intensity mapping (LIM) of emission from star-forming galaxies can be used to measure the baryon acoustic oscillation (BAO) scale as far back epoch reionization. This provides a standard cosmic ruler constrain expansion rate Universe at redshifts which cannot directly probed otherwise. In light growing tension between measurements current using local distance ladder and those inferred microwave background, extending constraints on history bridge late early is paramount importance. Using...
The possibility that a relevant fraction of the dark matter might be comprised Primordial Black Holes (PBHs) has been seriously reconsidered after LIGO's detection $\sim 30 M_{\odot}$ binary black holes merger. Despite strong interest in model, there is lack studies on possible cosmological implications and effects parameters inference. We investigate correlations with other standard using cosmic microwave background observations, finding significant degeneracies, especially tilt primordial...
When combining data sets to perform parameter inference, the results will be unreliable if there are unknown systematics in or models. Here we introduce a flexible methodology, BACCUS: BAyesian Conservative Constraints and Unknown Systematics, which deals conservative way with problem of combination, for any degree tension between experiments. We parameters that describe bias each model class A posterior is then obtained by marginalization both over these shifts width their prior. contrast...
We study the possibility to use line-intensity mapping (LIM) seek photons from radiative decay of neutrinos in cosmic neutrino background. The Standard Model prediction for rate these decays is extremely small, but it can be enhanced if new physics increases electromagnetic moments. will appear as an interloper astrophysical spectral lines. propose that neutrino-decay line identified with anisotropies LIM clustering and also voxel intensity distribution. Ongoing future experiments...