S10 - P. Muiño, The Higgs boson, 10 years after its discovery

14 Dezembro 2022, 14:00 • Maria Margarida Cruz

Abstract:  On 4th of July 2012, the ATLA and CMS collaborations at CERN announced the discovery of a particle compatible with being the Higgs boson of the Standard Model of Particle Physics (SM). The discovery appeared in all major newspapers all around the world. Since that date, the efforts of both collaborations have focused on the measurement of the Higgs boson properties. The aim of these studies is twofold. On the one hand, it is necessary to probe the SM predictions. On the other hand, the Higgs boson may provide answers to some of the most important questions in particle physics today, such as the origin of the matter-antimatter asymmetry of the Universe, or the nature of dark matter. In this seminar, I will review the current experimental status on the understanding of the Higgs boson and the future directions of research in this area

S9 - Víctor Almendros Abad, Exploring the formation of brown dwarfs in massive young clusters

7 Dezembro 2022, 14:00 • Maria Margarida Cruz

Abstract:  Young clusters and star-forming regions are home to a large number of substellar objects. Brown dwarf theories predict that high gas or stellar densities, as well as the presence of massive stars, may boost the incidence of newly formed brown dwarfs. However, studies of their populations in nearby regions have found consistent formation rates of 2-5 young brown dwarfs per 10 newborn stars. The next frontier in substellar studies is the exploration of massive star clusters, characterized by significantly different environments. In this contribution, I will present our latest results in two massive star clusters: RCW 38 and NGC 2244, which include, for the first time, hints of the effect of massive stars in the formation of brown dwarfs.

S8 - Felix Riehn, Ultra High Energy Cosmic Rays

30 Novembro 2022, 14:00 • Maria Margarida Cruz

Abstract:  Cosmic Rays (CRs) are high-energy particles, impinging on the Earth from outer space. Most of them are ionized atomic nuclei. CRs with energies exceeding 10^20 eV have been measured. This is outstandingly high, nearly a million times higher than the record of human-made accelerators, the LHC. Very few astrophysical objects seem capable of reaching such energy levels and it is still a mystery how they can achieve it. The Pierre Auger Observatory, located near the town Malargüe in Argentina, is the world's largest detector for CRs. The scientific questions it tries to answer are: What are the sources and acceleration mechanisms of ultra high energy CRs? Do we understand particle acceleration and physics at energies well beyond the LHC scale? What is the fraction of protons, photons, and neutrinos in cosmic rays at the highest energies? Moreover, understanding these processes will shed light into the unknown mechanisms driving the most extreme objects of the Universe. In this seminar I will explain how CRs are detected at the Pierre Auger Observatory, give a brief overview of our current understanding of the origin of CRs, and hint at what we hope to learn in the future.

S7 - Alain Aspect, From the Einstein-Bohr debate to quantum information: A new quantum revolution (on line seminar)

23 Novembro 2022, 14:00 • Maria Margarida Cruz

S6 - C.Fontanive, The effects of binary companions on planet formation and evolution

16 Novembro 2022, 14:00 • Maria Margarida Cruz

Abstract:  While numerous exoplanets have now been uncovered in stellar binaries, the impact of companion stars on planet formation and evolution is still not understood. In this talk, I will present results of population trends seen among the known sample of planets in multiple star systems, which allows us to investigate the effects of stellar binarity on the resulting planetary architectures. In particular, observations of stars hosting high-mass close-in giant planets find an excess of binary companions on few hundred AU separations, suggesting that such systems may provide favourable conditions for the formation of the observed inner companions. I will also show results from simulations of circumstellar disks adapted to binary star environments, which indicate that certain binary configurations may help trigger the formation of giant planets.