AN XMM-NEWTON EPIC X-RAY VIEW OF THE SYMBIOTIC STAR R AQUARIIThe Astrophysical Journal Letters
Depth XMM-Newton EPIC observations reveals in unprecedented detail the spatial distribution of diffuse soft X-ray emission, with a bipolar morphology spatially correlated with the optical nebula. The extended X-ray emission shares the same dominant soft X-ray-emitting temperature as the clumps in the jet-like feature resolved by Chandra in the vicinity of the binary system. The harder component in the jet might suggest that the gas cools down; however, the possible presence of nonthermal emission produced by the presence of a magnetic field collimating the mass ejection cannot be discarded. We propose that the ongoing precessing jet creates bipolar cavities filled with X-ray-emitting hot gas that feeds the more extended X-ray bubble as they get disrupted.
3D MAPPING OF THE WOLF-RAYET NEBULA M 1-67: CLUES FOR POST-COMMON ENVELOPE EVOLUTION IN MASSIVE STARSMonthly Notices of the Royal Astronomical Society
We present a 3D mapping of the Wolf-Rayet (WR) nebula M 1-67 around WR 124. We obtained high-resolution San Pedro Mártir (SPM) Manchester Echelle Spectrograph (MES) observations along 17 long-slit positions covering all morphological features in M 1-67. We are able to unveil the true morphology of M 1-67 and its kinematics by interpreting the SPM MES observations by means of the 3D modelling tool for Astrophysics SHAPE. Our SHAPE model that best reproduces the SPM MES data includes three concentric bipolar structures composed by a hollow ellipsoidal structure and a torus. In addition, the model requires the presence of expanding jets and broken blisters in order to reproduce specific spectral features.
TOMOGRAPHY OF THE UNIQUE ONGOING JET IN THE PLANETARY NEBULA NGC 2392The Astrophysical Journal
Jets (fast collimated outflows) are claimed to be the main shaping agent of the most asymmetric planetary nebulae (PNs), as they impinge on the circumstellar material at late stages of the asymptotic giant branch phase. The first jet detected in a PN was that of NGC 2392, yet there is no available image because of its low surface brightness contrast with the bright nebular emission. Here we take advantage of the tomographic capabilities of Gran Telescopio de Canarias Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía high-dispersion integral field spectroscopic observations of the jet in NGC 2392 to gain unprecedented details of its morphology and kinematics. The jet of NGC 2392 is found to emanate from the central star, break through the walls of the inner shell of this iconic PN and extend outside the nebula's outermost regions with an S-shaped morphology suggestive of precession. At odds with the fossil jets found in mature PNs, the jet in NGC 2392 is currently being collimated and launched..
THE DECLINE AND FALL OF THE YOUNGEST PLANETARY NEBULAThe Astrophysical Journal
The Stingray Nebula, a.k.a. Hen3-1357, appeared for the first time in 1990 when bright nebular lines and radio emission that had not been observed before were unexpectedly discovered. In the ensuing years, the nebula faded precipitously. We report changes in shape and large decreases in its nebular emission-line fluxes based on well-calibrated images obtained by the Hubble Space Telescope in 1996 and 2016. Hen3-1357 is now a "recombination nebula".
THE INSIDE-OUT PLANETARY NEBULA AROUND A BORN AGAIN STAR
Here, we report on the exceptional case of HuBi1, a double-shell planetary nebula whose inner shell presents emission from low-ionization species close to the star and emission from high-ionization species farther away. Spectral analysis demonstrates that the inner shell of HuBi 1 is excited by shocks, whereas its outer shell is recombining. (Nature Astronomy | Vol 2 | October 2018 | 784–789)
DON'T STOP NOVAE
Ancients coined the term “novae” to describe the appearance of new stars in the sky that faded away after a few weeks or months. As comets and eclipses, these were considered premonition for future events. Nowadays, astronomers use this term to designate an explosive event on the surface of a white dwarf star, a compact stellar remnant with the mass of our Sun compressed to the size of the Earth. In a nova event, the material accreted onto the surface of the white dwarf from a late type binary companion reaches a critical mass and, under the effects of the high gravity of the white dwarf, a thermonuclear runaway is ignited. Material is ejected at speeds of hundreds to even a few thousands km/s in a nova explosion. This material forms a nova shell that expands swiftly, and soon can be resolved by space and ground-based telescopes.
The expansion of nova shells can be witnessed in time-scales of decades or even only a few years in some cases (e.g., Sab 142, Santamaría et al. 2019). Textbook models based on simple assumptions predict that the expansion velocity of a nova shell slows down to 50% of its initial value after 50—100 years. To test this classical prediction, high-quality images of nova shells in astronomical archives have been complemented with contemporary sub-arcsec images obtained at the Nordic Optical Telescope in the island of La Palma to investigate the present expansion of five nova shells with ages ranging from 50 to 130 years (Santamaría et al. 2020). Contrary to the theoretical expectations, the nova shells in our sample have a free expansion that will take effect until their very end, when they dilute into the interstellar medium (Santamaría et al. 2022). Apparently, the mechanical energy and momentum of the material in a nova shell is sufficiently large to sweep away the circumstellar material around the white dwarf. The expansion of the nova shells included in this study is notable in the “timelapse” movie of DQ Her, a cataclysmic variable system that experienced an outburst on December 1934.
Jesús Alberto Toalá Sanz
Winner Cátedra de Investigación Marcos Moshinsky 2020
Fundación Marcos Moshinsky
With this project, Jesús Toalá intend to search and characterise the extended X-ray emission produced in novae explosions through the analysis of high quality observations and unprecedented numerical simulations trying to search for clues in order to understand nova events.
Winner Cátedra de Investigación Marcos Moshinsky 2019
Fundación Marcos Moshinsky
Through the development of Magneto-Hydrodynamic models combined with polarimetric (spectrum and observations), Laurence Sabin will study the magnetic fields in evolved Solar-type stars. The project aims to define the dynamic effects of stellar magnetism on the envelopes of these objects and to study the processes of magnetic release of material.
Gerardo Ramos Larios
Winner Cátedra de Investigación Marcos Moshinsky 2017
Fundación Marcos Moshinsky
By means of high-resolution 2D hydrodynamic simulations, our group studied evolved stars and planetary nebulae that have rings and arcs around them. We found that the interaction of the central star's fast wind and the ionization flux, eventually disrupt and destroy these arcs and rings.
Morelia, Mexico 2018 Guadalajara, Mexico 2019 APN7, Hong Kong 2017
Granada, Spain 2018 Granada, Spain 2019 Granada, Spain 2019
Guadalajara, Mexico 2021 Granada, Spain 2022 Granada, Spain 2022
Guadalajara, Mexico 2022 Morelia, Mexico 2023 Morelia, Mexico 2023
Granada, Spain 2018 Ensenada, Mexico 2019 Leiden, Netherlands 2019
APN6, Mexico 2013 OAN-SPM, Mexico 2020 Morelia, Mexico 2019