A5052160541- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Scientific Research and Discoveries
- Gamma-ray bursts and supernovae
- CCD and CMOS Imaging Sensors
- Solar and Space Plasma Dynamics
- Astro and Planetary Science
- Adaptive optics and wavefront sensing
- Space Exploration and Technology
- Astronomical Observations and Instrumentation
- Atomic and Molecular Physics
- Impact of Light on Environment and Health
- Geophysics and Gravity Measurements
- Mechanics and Biomechanics Studies
- Tribology and Lubrication Engineering
- Phase Equilibria and Thermodynamics
- Lightning and Electromagnetic Phenomena
- Geomagnetism and Paleomagnetism Studies
- Astronomical and nuclear sciences
- Spectroscopy and Laser Applications
- Pharmacological Effects and Assays
- Ionosphere and magnetosphere dynamics
- Computational Physics and Python Applications
Universidad Complutense de Madrid
2018-2024
Lund University
2023-2024
Agora
2024
Universidad Nacional Autónoma de México
2011-2023
Sorbonne Paris Cité
2022
Centre National de la Recherche Scientifique
2022
Université Paris Sciences et Lettres
2022
Université Paris Cité
2022
Ensenada Institute of Technology
2022
Hebrew University of Jerusalem
2016-2019
We use Gaia DR2 magnitudes, colours and parallaxes for stars with G<12 to explore a 15-dimensional space that includes simultaneously the initial mass function (IMF) non-parametric star formation history (SFH) Galactic disc. This inference is performed by combining Besancon Galaxy Model fast approximate simulations (BGM FASt) an Bayesian computation algorithm. find in data imprint of burst 2-3 Gyr ago, thin disc domain, present rate (SFR) about 1 Msun. Our results show decreasing trend SFR...
Context. Mergers and tidal interactions between massive galaxies their dwarf satellites are a fundamental prediction of the Lambda-cold dark matter cosmology. These events thought to provide important observational diagnostics non-linear structure formation. Stellar streams in Milky Way Andromeda spectacular evidence for ongoing satellite disruption. However, constructing statistically meaningful sample beyond Local Group has proven daunting challenge, full potential deepening our...
High-resolution N-body simulations using different codes and initial condition techniques reveal two behaviours for the rotation frequency of transient spiral arms like structures. Whereas unbarred discs present nearly corotating with disc particles, strong barred models (bulged or bulgeless) quickly develop a bar–spiral structure dominant in density, pattern speed almost constant radius. As bar strength decreases arm departs from rigid behaves similar to case. In models, we detect space...
ABSTRACT Using an isolated Milky Way-mass galaxy simulation, we compare results from nine state-of-the-art gravito-hydrodynamics codes widely used in the numerical community. We utilize infrastructure have built for AGORA High-resolution Galaxy Simulations Comparison Project. This includes common disk initial conditions, physics models (e.g., radiative cooling and UV background by standardized package Grackle ) analysis toolkit yt , all of which are publicly available. Subgrid such as Jeans...
Context. The Large and Small Magellanic Clouds (LMC SMC, respectively) are the brightest satellites of Milky Way (MW), for last thousand million years they have been interacting with one another. As observations only provide a static picture entire process, numerical simulations used to interpret present-day observational properties these kinds systems, most them focused on attempting recreate neutral gas distribution characteristics through hydrodynamical simulations. Aims. We present...
Context. The internal kinematics of the Large Magellanic Cloud (LMC) have been studied in unprecedented depth thanks to excellent quality Gaia mission data, thus revealing disc’s non-axisymmetric structure. Aims. We seek constrain LMC bar pattern speed using astrometric and spectroscopic data from mission. Methods. applied three methods evaluate by measuring it via: Tremaine-Weinberg (TW) method, Dehnen a bisymmetric velocity (BV) model. These provide additional information on properties,...
We study the components of cool and warm/hot gas in circumgalactic medium (CGM) simulated galaxies address relative production OVI by photoionization versus collisional ionization, as a function halo mass, redshift, distance from galaxy center. This is done utilizing two different suites zoom-in hydro-cosmological simulations, VELA (6 halos; $z>1$) NIHAO (18 to $z=0$), which provide broad theoretical basis because they use codes physical recipes for star formation feedback. In all halos...
Context: The high quality of the Gaia mission data is allowing to study internal kinematics Large Magellanic Cloud (LMC) in unprecedented detail, providing insights on non-axisymmetric structure its disc. Aims: To define and validate an improved selection strategy distinguish LMC stars from Milky Way foreground. check possible biases that assumed parameters or sample contamination can introduce analysis using data. Methods: Our based a supervised Neural Network classifier as much DR3...
Context. Tidal ring galaxies (TRGs) are rarely observed in the local universe due to their intrinsically transient nature. The tidal structures result of strong interactions between gas-rich stellar disks and smaller galactic systems, do not last longer than ∼500 Myr. Therefore, these perfect scenarios which look for debris recently accreted dwarf systems. Aims. Our goal is study low surface brightness around TRG NGC 922 revise hypothesis its formation light new data. Methods. We present...
Abstract We present a suite of high-resolution cosmological zoom-in simulations to z = 4 10 12 M ⊙ halo at 0, obtained using seven contemporary astrophysical simulation codes (A rt-I , E nzo R amses C hanga G adget-3 ear and izmo ) widely used in the numerical galaxy formation community. The physics prescriptions for gas cooling heating star are same as ones our previous Assembling Galaxies Resolved Anatomy (AGORA) disk comparison but now account effects processes such expansion universe,...
Abstract We analyze the circumgalactic medium (CGM) for eight commonly-used cosmological codes in AGORA collaboration. The are calibrated to use identical initial conditions, cosmology, heating and cooling, star formation thresholds, but each evolves with its own unique code architecture stellar feedback implementation. Here, we results of these simulations terms structure, composition, phase dynamics CGM. show properties such as metal distribution, ionization levels, kinematics effective...
We analyze and compare the satellite halo populations at $z\sim2$ in high-resolution cosmological zoom-in simulations of a $10^{12}\,{\rm M}_{\odot}$ target ($z=0$ mass) carried out on eight widely-used astrophysical simulation codes ({\sc Art-I}, {\sc Enzo}, Ramses}, Changa}, Gadget-3}, Gear}, Arepo-t}, Gizmo}) for {\it AGORA} High-resolution Galaxy Simulations Comparison Project. use slightly different redshift epochs near $z=2$ each code (hereafter ``$z\sim2$') which are same stage halo's...
Abstract In this fourth paper from the AGORA Collaboration, we study evolution down to redshift z = 2 and below of a set cosmological zoom-in simulations Milky Way mass galaxy by eight leading hydrodynamic simulation codes. We also compare CosmoRun suite with dark matter-only same analyze general properties halo at 4 3, before last major merger, focusing on formation well-defined rotationally supported disks, mass–metallicity relation, specific star rate, gas metallicity gradients,...
We analyse the distribution and origin of OVI in Circumgalactic Medium (CGM) dark-matter haloes $\sim 10^{12}$ M$_\odot$ at $z\sim1$ VELA cosmological zoom-in simulations. find that inflowing cold streams is primarily photoionized, while bulk volume it collisionally ionized. The photoionized component dominates observed column density large impact parameters ($\gtrsim 0.3 R_{\rm vir}$), ionized closer in. most collisional OVI, by mass, resides relatively thin boundaries streams. discuss how...
We introduce a new set of eight Milky Way-sized cosmological simulations performed using the AMR code ART + Hydrodynamics in LCDM cosmology. The zoom-in covers present-day virial masses 0.83-1.56 x 10^12 msun range and is carried out with our simple but effective deterministic star formation (SF) ``explosive' stellar feedback prescriptions. work focused on showing goodness simulated ``field' galaxies. Our results are as follows. (a) circular velocity curves galaxies nearly flat. (b) Runs...
Recent evidence of extremely metal-rich stars found in the Sombrero galaxy (M104) halo suggests that this has undergone a recent major merger with relatively massive galaxy. In paper, we present wide-field deep images M104 outskirts obtained 18-cm amateur telescope purpose detecting any coherent tidal features from possible merger. Our new data, together model inner and scattered light around field, allow us to trace for first time full path stream on both sides disk We fully characterize...
We map the kinematics of stars in simulated galaxy disks with spiral arms using velocity ellipsoid vertex deviation (l$_v$). use test particle simulations, and for first time, fully self-consistent high resolution N-body models. compare our maps Tight Winding Approximation model analytical predictions. see that all barred models rotate closely to a rigid body manner values correlate density peaks position bounded by overdense underdense regions. In such cases, sign changes from negative...
Context. Complex models recently became available for studying the dynamics of disk galaxies such as Milky Way (MW). These include global from dwarf satellite galaxies, dark matter halo structure, gas infall, and stellar disks in a cosmological context. Aims. We use MW model suite high-resolution hydrodynamical simulations named GARROTXA to establish relationship between vertical disturbances seen its galactic multiple perturbations halo, satellites, gas. Methods. calculated bending modes...
ABSTRACT We introduce a new set of simulations Milky Way (MW)-sized galaxies using the AMR code ART + hydrodynamics in Λ cold dark matter cosmogony. The simulation series is called GARROTXA and it follows formation halo/galaxy from z = 60 to 0. final virial mass system ∼7.4 × 10 11 M ⊙ . Our results are as follows. (a) Contrary many previous studies, circular velocity curve shows no central peak overall agrees with recent MW observations. (b) Other quantities, such <?CDATA $M\_\ast $?> (6 )...
We study the vertical perturbations in galactic disc of Milky Way-size high-resolution hydrodynamical cosmological simulation named GARROTXA. detect phase spirals projection $Z- V_{Z}$ disc's stellar particles for first time this type simulations. Qualitatively similar structures were detected recent Gaia data, and their origin is still under study. In our model spiral-like space are present a wide range times locations across disc. By accounting an evolving mix populations, we observe that,...
Stellar tidal streams are a key tracer of galaxy evolution and have the potential to provide an indirect means for tracing dark matter. For Local Group, many diffuse substructures been identified their link has traced. However, Group does not offer statistically significant sample stellar streams. Thus, analysis larger beyond is required better probe frequency characteristics these verify whether properties in agreement with predictions Lambda CDM model its implementation cosmological...
We investigate two topics regarding solar mass FGK-type stars, the lithium rotation connection (LRC) and existence of "lithium desert". determine minimum critical velocity ($v \sin i$) related with LRC separating slow from rapid stellar rotators, as being 5 km s$^{-1}$. This value also split different properties. For first time we explore behaviour for some associations ages between 45 Myr 120 Myr. allows us to study age dependence at beginning general spin down stage low which starts $\sim$...
Context. Stellar tidal streams are the result of interactions between a central galaxy and lower mass systems such as satellite galaxies or globular clusters. For Local Group, many diffuse substructures have been identified their link to evolution has traced. However, it cannot simply be assumed that Milky Way M 31 representative class. Thus, larger sample analogue beyond Group is required bolster broader generalisation underlying theory. Aims. We want detect photometrically characterise...
We model the effects of spiral arms Milky Way on disk stellar kinematics in Gaia observable space. also estimate capabilities detecting predicted signatures. use both controlled orbital integrations analytic potentials and self-consistent simulations. introduce a new strategy, which consists comparing symmetric Galactic longitudes (+l -l), particular median transverse velocity (from parallaxes proper motions). This approach does not require assumption an axisymmetric model. The typical...
MEGARA is the new generation IFU and MOS optical spectrograph built for 10.4m Gran Telescopio CANARIAS (GTC). The project was developed by a consortium led UCM (Spain) that also includes INAOE (Mexico), IAA-CSIC UPM (Spain). instrument arrived to GTC on March 28th 2017 successfully integrated commissioned at telescope from May August 2017. During on-sky commissioning we demonstrated powerful robust provides intermediate-to-high spectral resolutions RFWHM ~ 6,000, 12,000 20,000 an...