Recent Talks

About half of the stars in our Galaxy are born in binary systems meaning that their evolution might be affected by the presence of a companion. Many aspects of binary interaction are still unknown so understanding the products that result from interacting systems is crucial to unravel the physical mechanisms involved. A prototypical example of such post-interaction binary systems in the low- and intermediate-mass regime are Barium (Ba) stars. Ba stars are main-sequence or giant stars which show an enhancement of chemical elements that should not yet be overabundant at these evolutionary stages. Currently, it is widely accepted that these chemicals were transferred from a more evolved companion during a phase of mass transfer and that this companion evolved into a cool white dwarf. Understanding the orbital properties of these systems, as well as the stellar properties of the Ba star and its polluter, is the key to the system’s interaction history.

In the last years, the synergy between Gaia data, of unprecedented quality, high-resolution spectroscopy, long-term radial-velocity monitoring programmes, and state-of-the-art stellar and binary evolution models has contributed to a better understanding of the properties of Ba stars and provided new observational constraints to theoretical studies. The new Hertzsprung-Russell diagrams of Ba stars allowed us to accurately determine their evolutionary status and their masses. Additionally, we have recently determined the orbital properties of many main-sequence Ba stars, much less studied until now than their giant counterparts, which led to a thorough comparison of the properties of the two samples. The comparison between the distributions of masses, periods and eccentricities that resulted from this analysis allowed us to investigate the evolution of Ba-star systems between these two phases. Our models show that a second stage of binary interaction, this time between the main-sequence Ba star and its white-dwarf companion, also takes place in some systems, affecting the distribution of orbits observed among Ba giants.

Zoom link:   https://rediris.zoom.us/j/96557655189

Using deep photometry SBFs have been traditionally used to determine galaxy distances. We have recentlycomputed SBF spectra of stellar populations at moderately high resolution,which are fully based on empirical stellar spectral libraries. We show that the SBF spectraprovide new means to perform the stellar population studies, which, so far, have been tackled on the basis of the mean properties. We find that theSBFs are able to unveil very metal-poor components at the one percent level, which are not possible to disentangle with the standard analysis. In massive Early-Type Galaxies suchmetal-poor components correspond to the first stages in their chemicalenrichment and, therefore, the SBFs provide stringent constrains on their formation.

https://rediris.zoom.us/j/92233220080

The shell (or command-line) is the most commonly used (for advanced operations) interface to Unix-like operating systems.
In this session we'll introduce some of the most commonly used command-line/shell features and how they may be used in a hypothetical research project, using real astronomical data sets.
The session plan (with a listing of used commands and short explanation) is available here: https://gitlab.com/makhlaghi/smack-talks-iac/-/blob/master/smack-2-shell.md

https://rediris.zoom.us/j/98301657954

In the rapidly changing world of exoplanets, a new class of planets has emerged recently: the so called Ultra-Hot Jupiters, which have no analogue in our own solar system. Characterised by their short orbits and proximity to their host star, these worlds receive thousands of times the Earth’s insolation and have effective temperatures above 2000 K, making them intriguing candidates to study the most extreme atmospheric environments. A notable feature of these high temperatures is that the transmission spectra of these planets are rich in atomic metal lines, which provide new probes into the chemistry and dynamics of their atmospheres. I will highlight what we have recently learned about Ultra-Hot Jupiter atmospheres and focus on what knowledge can be derived directly from ground-based observations via transmission spectroscopy.

Connect to the following zoom link if you want to ask questions to the speaker:

https://rediris.zoom.us/j/96593309648

Re-ionisation followed the dark ages when enough stars and galaxies had been formed that their ionising output was sufficient for the task. Population III stars and star-forming galaxies started the re-ionisation process by forming primordial bubbles of ionised gas. These bubbles grew, illuminated by galaxies with strong Lyman continuum, and merged, till the entire Universe became ionised. The epoch corresponding to red-shift 6.5 is especially interesting as we now know the Universe became re-ionised by redshift ~5.5-6. High-z Lyα emitters are perhaps the most important witnesses of the re-ionisation process. Indeed, at redshifts larger than 6, Lyα sources would be undetectable, unless they are located within sizeable bubbles of ionised gas. I will show that a proto-cluster of Lyα emitting galaxies, spectroscopically confirmed at redshift 6.5, is within one such large ionised super-bubble. The kinds of bubbles that through percolation completed the re-ionisation of the universe.

Zoom link  https://rediris.zoom.us/j/94401326592

Short Meetings on Astro Computing Knowledge (SMACK) are a series of talks, or more appropriately 'live demonstrations', presented in the Instituto de Astrofísica de Canarias (IAC), targeting graduate students and researchers.  The main aim of the talks is to demonstrate the use and benefits of basic software tools that are commonly required for astronomical research. These talks will be showcasted at IAC Talks and recorded for easy future reference by the community.

The 1st SMACK is a brief introduction to the linux shell and the basic tools that come with it. We'll assume no previous knowledge and include a brief history of the POSIX standard.

Multi-conjugate adaptive optics (MCAO) has been proved to obtain the high-resolution images with a large field of view in solar observation. In this talk, after briefly introducing the basic principle and the development status of solar MCAO, I will give the progress of MCAO research based on the 1-m New Vacuum solar Telescope (NVST) in China. A solar MCAO experiment system had been successfully developed in 2017, and the MCAO-corrected high-resolution sunspots images were acquired. After that, a new MCAO system is being developed as an a regularly operating instrument for scientific observations of the sun for the NVST.

Se retransmitirá en directo, mediante streaming, un seminario compuesto de charlas cortas impartidas por trabajadoras del Instituto de Astrofísica de Canarias de todas las áreas del centro.

In this talk I will present the current status of the Calar
Alto observatory. I will review the most important highlights published
in 2019, as well as the legacy programs and instrumental developments
ongoing at the observatory at present. Finally, I will summarize the
recent call for public surveys and new instrumentation, still open, that
will be presented in the RIA workshop to be held at IAA headquarters in
March 2020.

Mindfulness o atención plena es un estado de la mente que permite estar atento al momento presente con aceptación. Y describe también la técnica psicológica que permite alcanzar este estado. Mindfulness se asocia a una gran bienestar físico y psicológico y por eso su práctica se está extendiendo a nivel internacional y se aplica en el área de la salud, la educación y las organizaciones.
En el coloquio sentaremos las bases teóricas de mindfulness, realizaremos algunas prácticas básicas y analizaremos los mecanismos de acción y la utilidad de mindfulness en el día a día.