A5074555580- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Molecular Spectroscopy and Structure
- Atmospheric Ozone and Climate
- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Astronomy and Astrophysical Research
- Astrophysical Phenomena and Observations
- Galaxies: Formation, Evolution, Phenomena
- Astronomical Observations and Instrumentation
- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Spectroscopy and Laser Applications
- Scientific Research and Discoveries
- Atomic and Molecular Physics
- Advanced Thermodynamic Systems and Engines
- Geophysics and Gravity Measurements
- Radio Astronomy Observations and Technology
- Particle accelerators and beam dynamics
- Superconducting and THz Device Technology
- Magnetic confinement fusion research
- Pulsars and Gravitational Waves Research
- Archaeological and Historical Studies
- Historical Astronomy and Related Studies
Instituto de Astrofísica de Andalucía
2015-2024
Hospital Materno-Infantil
2023
Consejo Superior de Investigaciones Científicas
2004-2014
University of Göttingen
2013
Universitat de Barcelona
1989-2007
Universidad Nacional Autónoma de México
1997-2003
Center for Astrophysics Harvard & Smithsonian
2001-2002
Harvard University
2002
Union astronomique internationale
2002
Universidad de Guanajuato
2002
Abstract Investigating Protostellar Accretion (IPA) is a JWST Cycle 1 GO program that uses NIRSpec integral field units and MIRI Medium Resolution Spectrograph to obtain 2.9–28 μ m spectral cubes of young, deeply embedded protostars with luminosities 0.2–10,000 L ⊙ central masses 0.15–12 M . In this Letter, we report the discovery highly collimated atomic jet from Class 0 protostar IRAS 16253−2429, lowest-luminosity source ( bol = 0.2 ) in IPA program. The detected multiple [Fe ii ] lines...
We present observations of the afterglows and host galaxies three short-duration gamma-ray bursts (GRBs): 100625A, 101219A, 110112A. find that GRB 100625A occurred in a z = 0.452 early-type galaxy with stellar mass ≈4.6 × 109 M☉ population age ≈0.7 Gyr, 101219A originated star-forming at 0.718 ≈1.4 M☉, star formation rate ≈16 yr−1, ≈50 Myr. also report discovery optical afterglow 110112A, which lacks coincident to i ≳ 26 mag, we cannot conclusively identify any field as possible host. From...
Synchrotron emission is commonly found in relativistic jets from active galactic nuclei (AGNs) and microquasars, but so far its presence young stellar objects (YSOs) has not been proved. Here, we present evidence of polarized synchrotron arising the jet a YSO. The apparent magnetic field, with strength ~0.2 milligauss, parallel to axis, polarization degree increases towards edges, as expected for confining helical field configuration. These characteristics are similar those AGN jets, hinting...
We present L' and J-band high-contrast observations of HD169142, obtained with the VLT/NACO AGPM vector vortex coronagraph Gemini Planet Imager, respectively. A source located at 0".156+/-0".032 north host star (PA=7.4+/-11.3 degrees) appears in final reduced image. At distance (~145 pc), this angular separation corresponds to a physical 22.7+/-4.7 AU, locating within recently resolved inner cavity transition disk. The has brightness L'=12.2+/-0.5 mag, whereas it is not detected J band...
Understanding planet formation requires to discern how dust grows in protoplanetary disks. An important parameter measure disks is the maximum grain size present. This usually estimated through measurements of opacity at different millimeter wavelengths assuming optically thin emission and dominated by absorption. However, ALMA observations have shown that these assumptions might not be correct case disks, leading overestimation particle sizes underestimation disk's mass. Here, we present an...
ABSTRACT The first long-baseline ALMA campaign resolved the disk around young star HL Tau into a number of axisymmetric bright and dark rings. Despite very age Tau, these structures have been interpreted as signatures for presence (proto)planets. images triggered numerous theoretical studies based on disk–planet interactions, magnetically driven structures, grain evolution. Of special interest are inner parts disks, where terrestrial planets expected to form. However, emission from regions...
Jets and outflows are ubiquitous in the process of formation stars since outflow is intimately associated with accretion. Free–free (thermal) radio continuum emission centimeter domain these jets. The relatively weak compact, sensitive interferometers high angular resolution required to detect study it. One key problems determine how they accelerated collimated. Observations cm range most useful trace base ionized jets, close young central object inner parts its accretion disk, where optical...
Proxima could host a planet on ∼5-year orbit, which Gaia can confirm in the near future providing its exact mass.
Abstract We have conducted a survey of 328 protostars in the Orion molecular clouds with Atacama Large Millimeter/submillimeter Array at 0.87 mm resolution ∼0.″1 (40 au), including observations Very 9 toward 148 ∼0.″08 (32 au). This is largest multiwavelength this by an order magnitude. use dust continuum emission and to measure disk radii masses Class 0, I, flat-spectrum protostars, characterizing evolution these properties protostellar phase. The mean for are <?CDATA...
Investigating Protostellar Accretion is a Cycle 1 JWST program using the NIRSpec+MIRI integral field units to obtain 2.9--28 $\mu$m spectral cubes of five young protostars with luminosities 0.2-10,000 L$_{\odot}$ in their primary accretion phase. This paper introduces NIRSpec 2.9--5.3 data inner 840-9000 au spatial resolutions from 28-300 au. The spectra show rising continuum emission; deep ice absorption; emission H$_{2}$, H~I, and [Fe~II]; CO fundamental series absorption. Maps scattered...
Nitrogen-bearing complex organic molecules have been commonly detected in the gas phase but not yet interstellar ices. This has led to long-standing question of whether these form or The James Webb Space Telescope (JWST) offers sensitivity, spectral resolution, and wavelength coverage needed detect them ices investigate their abundance ratios are similar ice. We report first tentative detection CH 3 CN, C 2 H 5 CN simple molecule, N O, based on CN-stretch band toward three (HOPS 153, HOPS...
The structure and composition of simple ices can be modified during stellar evolution by protostellar heating. Key to understanding the involved processes are thermal chemical tracers that diagnose history environment ice. 15.2 $\mu$m bending mode $^{12}$CO$_2$ has proven a valuable tracer ice heating events but suffers from grain shape size effects. A viable alternative is weaker $^{13}$CO$_2$ isotopologue band at 4.39 which now become accessible high S/N with $\textit{James Webb}$ Space...
We present 6 cm VLA observations of nine regions with molecular or HH outflows that appear to be driven by young stellar objects low bolometric luminosity. Radio continuum emission at 3.6 had been detected previously toward the center symmetry 13 in these regions. With new we have able estimate spectral index wavelength range for 11 outflow central (Class 0 and Class I) sources. All indices obtained sources are positive consistent partially thick thermal free-free emission. discuss this...
Using high angular resolution (~025-005) Very Large Array (VLA) observations made at 3.6 cm, 1.3 and 7 mm during the period 1991-2004, we report detection of large proper motions in components radio continuum jet associated with high-mass young stellar object (YSO) HW2 star-forming region Cepheus A. The relative observed for two main outflow, moving away from central source nearly opposite directions, are order 140 mas yr-1, or ~480 km s-1 a distance 725 pc. northeast southwest lobes not...
We present Very Large Array observations at 7 mm that trace the thermal emission of large dust grains in HD 169142 protoplanetary disk. Our images show a ring enhanced radius ~25-30 AU, whose inner region is devoid detectable emission. interpret this as tracing rim an cavity or gap, possibly created by planet substellar companion. The appears asymmetric, with western part significantly brighter than eastern one. This azimuthal asymmetry reminiscent lopsided structures are expected to be...
We present the detection of a dust continuum source at 3-mm (CARMA) and 1.3-mm (SMA), 12CO(2-1) emission (SMA) towards L1451-mm dense core. These detections suggest compact object an outflow where no point mid-infrared wavelengths is detected using Spitzer. An upper limit for core bolometric luminosity 0.05 Lsun obtained. By modeling broadband SED interferometric visibilities simultaneously, we confirm that central heating needed to explain observations. This also shows data can be well...
A survey of the Milky Way disk and Magellanic System at wavelengths 21-cm atomic hydrogen (HI) line three 18-cm lines OH molecule will be carried out with Australian Square Kilometre Array Pathfinder telescope. The study distribution HI emission absorption unprecedented angular velocity resolution, as well molecular thermal emission, absorption, maser lines. area to covered includes Galactic plane (|b|< 10deg) all declinations south delta = +40deg, spanning longitudes 167deg through 360deg...
Here we present deep (16 mumJy), very high (40 mas) angular resolution 1.14 mm, polarimetric, Atacama Large Millimeter/submillimeter Array (ALMA) observations towards the massive protostar driving HH 80-81 radio jet. The clearly resolve disk oriented perpendicular to jet, with a radius of ~0.171 arcsec (~291 au at 1.7 kpc distance). continuum brightness temperature, intensity profile, and polarization properties indicate that is optically thick for R<170 au. linear dust emission detected...
We present results from the most comprehensive radio monitoring campaign towards closest star to our Sun, Proxima Centauri. report 1.1 3.1 GHz observations with Australian Telescope Compact Array over 18 consecutive days in April 2017. detect emission Centauri for of observing sessions, which spanned $\sim$1.6 orbital periods planet b. The is stronger at low-frequency band, centered around 1.6 GHz, and consistent expected electron-cyclotron frequency known star's magnetic field intensity...
We characterize protostellar multiplicity in the Orion molecular clouds using ALMA 0.87~mm and VLA 9~mm continuum surveys toward 328 protostars. These observations are sensitive to projected spatial separations as small $\sim$20~au, we consider source up 10$^4$~au potential companions. The overall fraction (MF) companion (CF) for protostars 0.30$\pm$0.03 0.44$\pm$0.03, respectively, considering from 20 10$^4$~au. MFs CFs corrected contamination by unassociated young stars a probabilistic...
We have carried out a deep, 3.6 cm radio continuum survey of young outflow sources using the Very Large Array in its A configuration providing subarcsecond resolution. The seven regions observed are L1448-N, IRAS 2 and 4 NGC 1333, L1551-NE, SSV 63 L1630, HH 124 IRS 2264, B335 IRS. first three these objects known from submillimeter observations to be multiple sources, we detect almost all components at cm. L1551-NE source is confirmed binary. find third system, which drives 24 jets. embedded...
We present Very Long Baseline Array proper-motion measurements of water masers toward two young stellar objects (YSOs) the W75 N star-forming region. find that these are remarkable for having a similar spectral type, being separated by 07 (corresponding to 1400 AU), and sharing same environment, but with strikingly different outflow ejection geometry. One source has collimated, jetlike at 2000 AU scale, while other shell 160 scale expanding in multiple directions respect central compact...
We present five epochs of VLBI water maser observations around the massive protostar Cepheus A HW2 with 0.4 mas (0.3 AU) resolution. The main goal these was to follow evolution remarkable linear/arcuate structures found in earlier observations. Comparing data our new observation those observed years before, we find that at "large" scales > 1" (700 regions emission persist, implying both surrounding medium and exciting sources masers have been relatively stable during time span. However,...