Charla de G. Raffelt: «Stars as Particle-Physics Laboratories: Old Ideas and New Developments»

Georg G. Raffelt, Max-Planck-Institut für Physik. His research is in the areas of theoretical astroparticle physics and cosmology. In particular, it revolves around weakly interacting particles (neutrinos, the hypothetical axion, or weakly interacting dark matter candidates), their role in astrophysics and cosmology.

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Charla de Miguel A. Pérez Torres: «SKA: the mother of all radio telescopes»

SKA

Miguel Á. Pérez Torres, research scientist at the Instituto de Astrofísica de Andalucía (IAA-CSIC, Granada, Spain) and collaborator of the DFTUZ

Abstract The Square Kilometre Array (SKA) project is an international effort to build the world’s largest radio telescope. The SKA is expected to conduct transformational science to improve our understanding of the Universe and the laws of fundamental physics, monitoring the sky in unprecedented detail and mapping it many times faster than any current facility.
The SKA  will not be a single telescope, but a collection of telescopes spread over long distances in the Southern Hemisphere. In this talk, I will give an overview of the SKA project and its science goals, which range from the cradle of life in exoplanets up to shedding light on the Epoch of Reionization and the Dark Ages of the Universe.

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Charla de Jacobo Varela: «Synergies in plasma physics: exoplanet habitability and radio emission» 🗓

Charla

Lecturer:  Jacobo Varela Rodríguez (Universidad Carlos III, Madrid)

Abstract: This presentation discusses synergies between different plasma physics fields, emphasising in the astrophysical plasmas. In particular, exoplanet habitability is a hot topic in the scientific community, devoted to developing new observational as well as numerical models dedicated to analyzing the exoplanet environment. In the last decade, MHD models are applied to study the magnetic field generation by dynamo effect in the convective layer of stars, the production of stellar winds as well as the interaction of the stellar wind with planetary magnetospheres. We show the last advances in the modelling efforts to analysis the effect of the space weather conditions on the exoplanet habitability, that is to say the interaction of the stellar wind and the exoplanet magnetosphere. In addition, the radio emission from exoplanet magnetospheres is numerically evaluated identifying trends regarding the space weather properties

Jueves 19 mayo, 12 horas, seminario de Física Nuclear

On-line (Zoom)

Cartel

 

Charla de Tomislav Terzić : «Measuring Lorentz invariance violation with Cherenkov telescopes – from observations to setting constraints»

Cherenkov telescopes are instruments optimized for detection of very high energy (VHE, E > 100 GeV) gamma rays from astrophysics sources. They play a crucial role in testing possible consequences of Quantum Gravity (QG), such as violation or deformation of Lorentz symmetry. In both cases, the photon dispersion relation is modified, making the photon group velocity energy dependent, and possibly modifying kinematics and dynamics of electromagnetic interactions. These tiny effects are vastly below the sensitivity of present-day laboratories. However, if real, they could be measured using VHE gamma rays of astrophysical origin. Cosmological distances that they cross serve as a natural amplifier for the QG effects. While no deviations from the special relativistic predictions have been detected, strong constraints have been set on modified photon dispersion relations.
In this session we will explain the process of testing implications of modified photon dispersion relations on VHE gamma rays using Cherenkov telescopes. We will cover different stages from observations, Cherenkov telescopes’ data analysis, statistical methods employed, and finally setting constraints on the QG energy scale.

Jueves 12 mayo, 12 horas, seminario de Física Nuclear, on-line  (Google Meet)

Cartel

Charla de Diego Blas: «Soundscape of gravitational waves: a new tool to access the fundamental blocks of the Universe»

Diego Blas is a researcher at UAB (Universidad Autónoma de Barcelona) and IFAE (Instituto de Física de Altas Energías). His research interests are in theoretical physics, gravitation and cosmology.

Abstract: In this talk, current and future efforts to detect gravitational waves from Earth and space observatories will be reviewed. Diego will also emphasise the physical consequences of these searchers, in particular regarding fundamental physics (primordial cosmology, dark matter, modified gravity…)

Viernes 6 mayo, 12 horas, seminario de Física Nuclear. On-line (Google-meet)

Charla de Diego Blas (cartel)

 

Charla de Héctor Gómez-Maluenda: Muography and Nuclear Safety: Reactors surveillance, and monitoring and waste qualification

muongraphy

Héctor Gómez-Maluenda ist a researcher at «Commissariat à l’énergie atomique et aux énergies alternatives» (CEA – France)

Abstract: The use of muons produced at the Earth’s atmosphere as radiation source for the scanning of big structures is usually referred as muography. Since first muography attempts by Alvarez in the 1970s, the range of applications of this technique has been broadened in the last years mainly due to the advances on the particle detectors used and to the improvements on the analysis techniques. Thus, different muography measurements have been done for vulcanology, archaeology, geotechnics or civil engineering. Among these different applications, the IRFU group (Institut de recherche sur les lois fondamentales de l’Universe – CEA – France) is developing since the last years several projects regarding Nuclear Safety. They include the characterisation of nuclear reactors and their real-time surveillance or the verification of waste containers. After a general introduction to muography, this seminar will be focused on these activities carried out at CEA and their main results, including those about first 3D reconstructions using this technique, passing from muography to muon tomography.

Jueves 5 mayo, 12 horas, seminario de Física Nuclear.

On-line https://rediris.zoom.us/j/89034851642 

Charla Héctor Gómez (folleto)

Link to the video

Charla de Carlos López Sanjuan: La evolución espectral de enanas blancas con J-PLUS

J-PLUS

Dr. Carlos López Sanjuan is a researcher at CEFCA (Centro de Estudios de Física del Cosmos de Aragón).

Abstract: White dwarfs are the degenerate compact remnants of stars with masses below 8 Msun. They do not have an internal source of energy and just cool down with time. In addition, they show a diversity of atmospheric compositions in their spectra, with sources presenting hydrogen (H) lines (DA type), helium (He) lines (DO and DB type), metal lines (DZ type), and featureless spectra (DC type) among others. In this seminar we present our recent work about the spectral evolution of white dwarfs with effective temperature (i.e., their age) using the Javalambre Photometric Local Universe Survey (J-PLUS). We analysed 5926 white dwarfs with r <= 19.5 mag in common between the white dwarf catalogue presented in Gentile Fusillo et al. 2021, defined from Gaia EDR3, and J-PLUS DR2. We estimated their effective temperature (Teff), surface gravity, parallax, and spectral type; and the probability of having a H-dominated atmosphere (p_H) for each source. Our analysis yields a 21 +- 3% increase in the fraction of He-dominated white dwarfs from Teff = 20000 K to  Teff = 5000 K.

Horario: 12:00, del jueves 10 de marzo, en el seminario de Física Nuclear. On-line

 

Saturnalia 2021: anuncio y programa

El solsticio de invierno se acerca de nuevo. Cómo pasa el tiempo! y con él el comienzo de nuestra conferencia anual de saturnalia.

Este año disfrutaremos de algunos de nuestros ponentes en vivo y en directo, mientras que otros nos deleitarán a distancia (mediante ZOOM en el enlace https://rediris.zoom.us/j/7818936953)

Nuestro formato vuelve a la carga

  • Duración: 20-23 de Diciembre, charlas a las 14:00 y las ~17:30
  • Formato: 2 charlas de cada día, 45 min + 15 de discusión
  • Ponentes: Rodrigo García Ruiz, Filiberto Ares, Chang Lee, Jacobo Asorey (TBC), Diego Blas, Javier Relancio, Mohammad Sharifian, Cristian Cogollos
  • Calificación: Todos los públicos (Hemos solicitado a los conferenciantes que al menos la primera mitad de las charlas sean de un nivel accesible, de modo que los estudiantes del Grado en Física son bienvenidos).

Podéis encontrar todos los detalles  (incluidos los de conexión) en la página de Saturnalia 21:

https://indico.capa.unizar.es/e/saturnalia21

 

Seminario CAPA: Bodo Schwabe on «Adaptive Mesh Refinement Simulations of Cosmological Scalar Fields» 🗺

This thursday 16th December 2021, 12:00 in the «Seminario de Física Atómica, Molecular y Nuclear» and ONLINE we will have a new CAPA/theory seminar :

Speaker: Bodo schwabe (Dep. Física Teórica, Universidad de Zaragoza)

Title: Adaptive Mesh Refinement Simulations of Cosmological Scalar Fields

The talk will be given in person in the Seminar room and will be broadcasted via ZOOM in this link: https://rediris.zoom.us/j/86416862083

CAPA indico record: https://indico.capa.unizar.es/event/20/

Abstract: Over the past 15 months that I have had the please to be part of the Departamento de Física Teórica I continued my broad research on adaptive mesh refinement (AMR) simulations of cosmological scalar fields. In this seminar talk I will highlight the main scientific results that are the product of my stay at the Universidad de Zaragoza. This includes a new numerical method for ultra-deep zoom-in simulations of cosmological structure formation with fuzzy dark matter allowing numerical analyses of Milky Way-sized halos. Additionally, I will present preliminary results of cosmological structure formation suppression in scenarios where fuzzy dark matter is considered as an admixture to cold dark matter. The same numerical techniques are utilized for gravitational collapse simulations of the inflaton field in the post-inflationary, matter dominated Universe. Finally, I will highlight numerical results of QCD axion evolution assuming PQ-symmetry breaking after inflation using AMR techniques to better resolve axion strings and axitons for increasingly realistic simulations.

 

Charla de Miguel Ángel Sánchez Conde sobre detección indirecta de Materia Oscura

Indirect Dark Matter

Dr. Miguel Ángel Sánchez Conde is a researcher at Universidad Autónoma de Madrid leading a group with a focus on gamma-ray dark matter searches, astroparticle physics and cosmological simulations.

Abstract: The nature of the dark matter (DM) in the Universe is one of the greatest mysteries of our time, and its quest of utmost relevance for the whole scientific community. Among the efforts currently ongoing, the search for annihilation or decay products of DM particle candidates like the WIMP already provided abundant information and allowed to set competitive constraints on the DM particle properties. In this review talk, I will summarize the current status of this ‘indirect’ search of DM, paying particular attention to results obtained with gamma-ray telescopes from the direction of the best astrophysical targets. I will finally discuss on future DM sensitivity prospects and new DM search opportunities.»

Horario: 12:00, del jueves 9 de diciembre, en el seminario de Física nuclear u on-line .

Charla financiada por el proyecto DGA del grupo GIFNA .

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