Recent Talks
List of all the talks in the archive, sorted by date.
Abstract
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.
Abstract
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
Abstract
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
Abstract
Abstract
Abstract
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.
Abstract
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
Unirse a la reunión Zoom
Abstract
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.
Abstract
On the Sun, the presence of magnetic flux at the photosphere is closely linked to (1) steady heating of the overlying atmosphere and (2) transient brightenings, the largest of which are flares. I will discuss statistical properties of both phenomena, with an emphasis on aspects of each that might apply to other astrophysical objects, such as other stars or stellar remnants, and perhaps AGNs. Regarding heating, power-law scalings have been found to relate magnetic flux with steady coronal emission in both soft X-ray (SXR) and EUV ranges. A key observation is that the details of magnetic structure (field strengths and their spatial gradients, including measured electric currents) appear not to affect heating rates. Similar SXR scalings have been reported for G,K, and M dwarfs and classical T-Tauri stars. Departures from such scalings, whether on the Sun, other stars, or other objects, might reveal important aspects of the heating mechanisms that drive steady emission, and should be sought. Regarding flaring, again a power-law scaling between magnetic flux and flare SXR emission has been found, but with a different exponent. Differences in these scalings suggest that steady heating fundamentally differs from flare heating, disfavoring the “nanoflare” hypothesis (i.e., that steady coronal heating arises from many weak, unresolved flares that are essentially scaled-down versions of larger flares). Analogous differences in the scalings of steady vs. flaring luminosities with magnetic flux on other objects could constrain processes driving each type of emission. Another key property of flares is that they extract energy from the magnetic field, which in the solar case leads to measurable changes in field strengths after flares – photospheric field strengths tend to increase, coronal fields tend to decrease. It is possible that analogous changes could be observed on other stars or objects (via, e.g., Zeeman or synchrotron methods).
Abstract
Se cuenta la historia de la integración del subsistema Fiber Link (FL) en el telescopio de 3.6 m del Observatorio de La Silla para alimentar el espectrógrafo NIRPS. NIRPS es un espectrógrafo de alta resolución y ultraestabilidad optimizado para el rango infrarrojo cercano del espectro. Compartirá foco con el instrumento HARPS y su finalidad principal es el estudio de exoplanetas. El subsistema FL permitirá alimentar al espectrógrafo con la luz procedente del telescopio y optimizará la estabilidad de todo el sistema.
Upcoming talks
- Incoming EU projects at the IACJohan Knapen, Jorge Martin CamalichTuesday May 21, 2024 - 12:30 GMT+1 (Aula)
- TBDMalin StanescuThursday May 23, 2024 - 10:30 GMT+1 (Aula)