Recent Talks

In this talk, I will review the recently discovered infinite-dimensional symmetries that emerge in the near horizon region of black hole horizons. I will explain how the conserved charges associated with those symmetries carry information of the black hole, and, in particular, about its thermodynamic properties. I will focus on the case of magnetized black holes; namely, black holes that are embedded in strong magnetic fields.

I discuss the dynamical interactions between the Milky Way and its satellite galaxies, focusing on the closest and most massive satellites - the Large Magellanic Cloud (LMC) and the Sagittarius dwarf galaxy. The former just has had its first close encounter with the Milky Way very recently, and the latter has been orbiting our Galaxy for several Gyr and is tidally disrupting, leaving a prominent tidal stream spanning the entire sky. Thanks to the abundant and precise observational data from the Gaia satellite and various spectroscopic surveys, we now have a very detailed view of the Sagittarius stream and the remnant. It appears that to reproduce its observed properties, one needs to take into account the gravitational effect of the LMC itself and the effect that it produces on the motion of the Milky Way: an intricate dance of three galaxies. The LMC also affects the motion of other streams and satellite galaxies in the outskirts of the Milky Way, and I discuss an approach for compensating these perturbations in the context of dynamical modelling of the Milky Way mass distribution and the analysis of satellite orbits.

The search for the primordial B-modes polarization in the cosmic microwave background (CMB) radiation,
carrying the signature of the primordial gravitational waves from the inflation epoch, motivated a significant
technological progress enabling the next generation of CMB instruments (e.g. CMB-S4, LiteBIRD)
to reach an unprecedented sensitivity. However, such a challenging detection demands a very high control
of the instrumental systematics and CMB foreground emissions.
Among those, the galactic dust polarized emission spectral dependence, not yet fully
characterized, could leave a high level of uncertainty in the cosmological polarization data
producing an ambiguous detection of the CMB B-modes.
Characterizing the dust spectral energy distribution (SED) spatial variations became one of
the most critical issues in the quest for primordial B-modes.
In the work that I will present we have used the release of the Planck satellite HFI data
obtained with the software Sroll2 (Delouis+2019, A&A 629, A38), in order to characterize
and compare the SEDs for polarization and total intensity.
The mean SEDs for dust polarization and total intensity from 353 to 100 GHz are confirmed
to be remarkably close. However, the data show evidence for spatial variations of the
polarization SED. These variations are correlated with variations of dust temperature
measured on total intensity data but the correlation is tight only in the Galactic plane.
At higher latitudes, by considering 90% of useful sky fraction and less, the amplitude of the dust
emission residuals in polarization suggests that an additional contribution, coming from
variations of the polarization angle, becomes dominant. Current models, which extrapolate
the SED spatial variations from total intensity to polarization, would be therefore grossly
simplifying and underestimating the foreground signal to CMB polarization.

 PyCOMPSs is a task-based programming in Python that enables simple sequential codes to be executed in parallel in distributed computing platforms. It is based on the addition of python decorators in the functions of the code to indicate those that can be executed in parallel between them. The runtime takes care of the different parallelization and resource management actions, as well as of the ditribution of the data in the different nodes of the computing infrastructure. It is installed in multiple supercomputers of the RES, like MareNostrum 4 and now LaPalma. The talk will present an overview of PyCOMPSs, two demos with simple examples and a hands-on in LaPalma on how we can parallelize EMCEE workloads.

Slides and Examples: https://gitlab.com/makhlaghi/smack-talks-iac

Desde el 2019, en el Departamento de Electrónica del Área de Instrumentación del Instituto de Astrofísica de Canarias (IAC) se ha estado trabajando para tener la capacidad de diseñar y medir circuitos integrados con diferentes procesos tecnológicos. Gracias al proyecto EMIAC (Equipamiento Microelectrónica IAC) del Plan Nacional de Infraestructuras y posteriormente en menor medida al Plan de Recuperación, Transformación y Resiliencia, se está avanzando en la creación y puesta en marcha del Laboratorio de Circuitos Integrados (LABIC). El objetivo de esta presentación es mostrar el estado actual del laboratorio así como las líneas futuras.

Unirse a ZOOM:

https://rediris.zoom.us/j/84979227061

Emisión en Youtube:

https://youtu.be/Ec3Ktstx32o

Uno de los principales problemas que afecta no solo a la astrofísica sino a otros sectores de investigación e industria a nivel nacional, es la fabricación de elementos ópticos. De esta forma el CSOA se concibe para cubrir parte de esa demanda, no solo para fabricar elementos óptico tradicionales (esféricos y cónicos) y superficies u elementos ópticos no convencionales (asféricas, formas caprichosas, etc.). Para ello, debe contar con toda la infra estructura de última generación en cuanto a fabricación respecta, tales como sierras, generadoras, pulidoras, equipos de metrología y de recubrimientos ópticos para entregar un producto completamente funcional según se requiera. En esta breve charla hablaré de gran parte del equipo que se ha adquirido y ha sido entregado, lo que va situando al CSOA con la capacidad de ir ofreciendo ya algunos servicios.

Se hará una revisión de la tecnología de imágenes médicas, y de los métodos para su análisis y visualización. También se prestará atención a modelos de transferencia de tecnología a empresas en este campo. La computación de imágenes médicas es un campo multidisciplinar que involucra a médicos, ingenieros y científicos. Los campos que destacaremos son los métodos automáticos y semiautomáticos de procesado e interpretación de imágenes médicas, destacando en los últimos años la inteligencia artificial, que ha dado lugar a nuevos campos de investigación y aplicación, tales como la radiómica y la radiogenómica. También se discutirán las sinergias con la tecnología astrofísica y algunas posibilidades de I+D y trasnferencia desde el IAC.

Youtube: https://youtu.be/E_AVrcyqrO0

Recent years have seen impressive development in cosmological simulations for spiral disc galaxies like the Milky Way. I present a suite of high-resolution magneto-hydrodynamic simulations that include many physical processes relevant for galaxy formation, including star formation, stellar evolution and feedback, active galactic nuclei and magnetic fields. I will discuss how these processes affect the formation of galactic discs, and what these simulations can tell us about the formation of the Milky Way, such as the properties of the Galaxy's putative last significant merger and its effect on the formation of the thick disc and stellar halo.