A5040112376- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Molecular Spectroscopy and Structure
- Astrophysical Phenomena and Observations
- Target Tracking and Data Fusion in Sensor Networks
- Astronomy and Astrophysical Research
- Spacecraft and Cryogenic Technologies
- Innovative Teaching and Learning Methods
- Phase Equilibria and Thermodynamics
- Neural Networks and Applications
- Gaussian Processes and Bayesian Inference
- Tribology and Lubrication Engineering
- Pulsars and Gravitational Waves Research
- Wikis in Education and Collaboration
- Neural Networks and Reservoir Computing
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Open Education and E-Learning
- Guidance and Control Systems
- Radar Systems and Signal Processing
- Advanced SAR Imaging Techniques
- Computational Physics and Python Applications
Universidad de Santiago de Chile
2021-2024
University of Chile
2021
Universidad Bernardo O'Higgins
2021
Niels Brock
2018-2021
University of Copenhagen
2019-2021
McMaster University
1985-2002
SICOM Systems (United States)
2002
Abstract Aerodynamic theory predicts that dust grains in protoplanetary disks will drift radially inward on comparatively short timescales. In this context, it has long been known the presence of a gap opened by planet can significantly alter dynamics. paper, we carry out systematic study employing long-term numerical simulations aimed at characterizing critical particle size for retention outside as function size, well various key parameters defining disk model. To end, perform multifluid...
The sample of planet-forming disks observed by high-contrast imaging campaigns over the last decade is mature enough to enable demographical analysis individual star-forming regions. We present full census Taurus sources with VLT/SPHERE polarimetric images available. whole sums up 43 targets (of which 31 have not been previously published) corresponding one-fifth Class II population in and about half such objects that are observable. A large fraction apparently made isolated faint (equally...
Abstract We present Atacama Large Millimeter/submillimeter Array 12-m, 7-m, and Total Power observations of the FU Orionis outbursting system, covering spatial scales ranging from 160 to 25,000 au. The high-resolution interferometric data reveal an elongated 12 CO(2–1) feature previously observed at lower resolution in CO(3–2). Kinematic modeling indicates that this can be interpreted as accretion streamer feeding binary system. mass infall rate provided by is significantly than typical...
Abstract Jupiter and Saturn formed early, before the gas disk dispersed. The presence of gap-opening planets affects dynamics embedded solids halts inward drift grains above a certain size. A barrier can explain absence calcium–aluminum-rich inclusions (CAIs) in chondrites originating from parent bodies that accreted inner solar system. Employing an interdisciplinary approach, we use μ -X-ray-fluorescence scanner to search for large CAIs scanning electron microscope small ordinary chondrite...
ABSTRACT Planet–disc interactions build up local pressure maxima that may halt the radial drift of protoplanetary dust, and pile it in rings crescents. ALMA observations HD 135344B disc revealed two thermal continuum stemming from ∼mm-sized dust. At higher frequencies inner ring is brighter relative to outer ring, which also shaped as a crescent rather than full ring. In near-IR scattered light images, modulated by two-armed grand-design spiral originating inside Such structures be induced...
The migration of planetary cores embedded in a protoplanetary disk is an important mechanism within planet-formation theory, relevant for the architecture systems. Consequently, planet actively discussed, yet often results independent theoretical or numerical studies are unconstrained due to lack observational diagnostics designed light migration. In this work we follow idea inferring behavior planets by means characteristic radial structures that they imprint disk's dust density...
Aims. Eruptive stars are a class of young stellar objects that show an abrupt increase in luminosity. These burst-like episodes thought to dominate the accretion process during Class 0 I stage. We present overview survey seven episodically accreting protostars carried out study their potentially complex circumstellar surroundings. Methods. The observations were performed with instrument SPHERE, mounted at Very Large Telescope. SPHERE is equipped extreme adaptive optics system allows...
The formation of giant planets has traditionally been divided into two pathways: core accretion and gravitational instability. However, in recent years, instability become less favored, primarily due to the scarcity observations fragmented protoplanetary disks around young stars low occurrence rate massive on very wide orbits. In this study, we present a SPHERE/IRDIS polarized light observation outbursting object V960 Mon. image reveals vast structure intricately shaped scattered with...
We present ALMA multiwavelength observations of the protoplanetary disk around nearby (d$\sim$100 pc) young solar analog MP Mus (PDS 66). These at 0.89 mm, 1.3 and 2.2 mm have angular resolutions $\sim$ 1", 0.05", 0.25", respectively, probe dust gas in system with unprecedented detail sensitivity. The appears smooth down to 4 au resolution observations, contrast most disks observed comparable spatial scales. has a radius 60$\pm$5 au, mass $0.14_{-0.06}^{+0.11} M_{\rm Jup}$, spectral index...
Dense stellar environments as hosts of ongoing star formation increase the probability gravitational encounters among systems during early stages evolution. Stellar interaction may occur through non-recurring, hyperbolic or parabolic passages (a so-called 'fly-by'), secular binary evolution, capture. In all three scenarios, strong perturbation is expected to manifest itself in disc structures around individual stars. Here, we present near-infrared polarised light observations that were taken...
High resolution ALMA observations revealed a variety of rich substructures in numerous protoplanetary disks. These structures consist rings, gaps and asymmetric features. It is debated whether planets can be accounted for these the dust continuum. Characterizing origin asymmetries as seen HD 163296 might lead to better understanding planet formation underlying physical parameters system. We test possibility crescent-shaped asymmetry disk through planet-disk interaction. The goal obtain...
ABSTRACT Warps have often been used to explain disc properties, but well-characterized examples are important due their role in evolution. Scattered light images of discs with central gaps revealed sharp warps, such that the outer rings shadowed by tilted inner discs. The near-infrared intensity drops along ring around T-Tauri star DoAr 44 interpreted terms a warp. We report new ALMA observations continuum at 230 and 350 GHz (at ∼10 au), epoch Spectro Polarimetric High-contrast Exoplanet...
Abstract The interpretation of molecular-line data using hydrodynamical simulations planet–disk interactions fosters new hope for the indirect detection protoplanets. In a model-independent approach, embedded protoplanets should be found at roots abrupt Doppler flips in velocity centroid maps. However, largest perturbation known an unwarped disk, disk HD 100546, leads to conspicuous flip that coincides with thick dust ring, contradiction terms ≳1 M jup body. Here we present ALMA observations...
[Full abstract in the paper] In recent years, protoplanetary disks with spiral structures have been detected scattered light, millimeter continuum, and CO gas emission. The mechanisms causing these are still under debate. A popular scenario to drive arms is one of a planet perturbing material disk. However, if disk massive, gravitational instability usually favored explanation. Multiwavelength studies could be helpful distinguish between two scenarios. So far, only handful observed both...
The nearby V4046 Sgr spectroscopic binary hosts a gas-rich disc known for its wide cavity and dusty ring. We present high resolution ($\sim$20 mas or 1.4 au) ALMA observations of the 1.3mm continuum which, combined with SPHERE--IRDIS polarised images well-sampled spectral energy distribution (SED), allow us to propose physical model using radiative transfer (RT) predictions. data reveal thin ring at radius 13.15$\pm$0.42 au (Ring13), radial width 2.46$\pm$0.56 au. Ring13 is surrounded by...
Recent imaging of the disc around V4046$\,$Sgr spectroscopic binary revealed concentric regions dust rings and gaps. The object's proximity expected equilibrated state due to its old age (>20$\,$Myr) make it a superb testbed for hydrodynamical studies in direct comparison observations. We employ two-dimensional simulations gas multiple species test whether observed structure conforms with presence giant planets embedded disc. then perform radiative transfer calculations sky images, which we...
The sample of planet-forming disks observed by high-contrast imaging campaigns over the last decade is mature enough to enable demographical analysis individual star-forming regions. We present full census Taurus sources with VLT/SPHERE polarimetric images available. whole sums up 43 targets (of which 31 have not been previously published) corresponding one-fifth Class II population in and about half such objects that are observable. A large fraction apparently made isolated faint (equally...
Eruptive stars are a class of young stellar objects that show an abrupt increase in their luminosity. These burst-like episodes thought to dominate the accretion process during 0/class I stage. We present overview survey seven episodically accreting protostars aimed at studying potentially complex circumstellar surroundings. The observations were performed with instrument SPHERE, mounted VLT. observed eruptive $H$-band near-infrared imager IRDIS and used polarimeter extract polarized light...
The eROSITA instrument on board Spectrum-Roentgen-Gamma has completed four scans of the X-ray sky, leading to detection almost one million sources in eRASS1 only, including multiple new binary candidates. We report analysis 1eRASS J085039.9-421151, using a ~55\,ks long NuSTAR observation, following its each scan. Analysis and spectra combination with X-shooter data optical counterpart provide evidence an red supergiant (RSG) companion, confirming previous results, although we determine...
We present ALMA multiwavelength observations of the protoplanetary disk around nearby (d$\sim$100 pc) young solar analog MP Mus (PDS 66). These at 0.89 mm, 1.3 and 2.2 mm have angular resolutions $\sim$ 1", 0.05", 0.25", respectively, probe dust gas in system with unprecedented detail sensitivity. The appears smooth down to 4 au resolution observations, contrast most disks observed comparable spatial scales. has a radius 60$\pm$5 au, mass $0.14_{-0.06}^{+0.11} M_{\rm Jup}$, spectral index...
The authors describe a high-speed systolic-based computer system designed to process real-life radar data in near real time. At the heart of is ten-cell Warp (systolic) machine. A digital recorder used input system, and color monitor displays output processing algorithms. permits large volumes time, results advanced signal-processing algorithms, has effect bringing environment inside laboratory for experimental studies or, equivalently, taking sophisticated outside into an operational...
Over the last few years there has been considerable interest in developing highly effective target tracking algorithms. This robust techniques is spawned by need to process data that often includes a large number of false detections and missed detections. These conditions are amplified detect track increasingly smaller targets as well harsh clutter conditions. Such ambiguities serve further exacerbate problem which must already produce plot assignments for closely spaced crossing targets....
Warps have often been used to explain disc properties, but well characterised examples are important due their role in evolution. Scattered light images of discs with central gaps revealed sharp warps, such that the outer rings shadowed by tilted inner discs. The near-IR intensity drops along ring around TTauri star DoAr44 interpreted terms a warp. We report new ALMA observations continuum at 230 GHz and 350 (at ~10 au), epoch SPHERE/IRDIS differential polarised imaging taken during...